图形界面系列教材（十二）- 表格综合练习

图形界面系列教材（十一）- 两种Swing下的日期控件 DatePicker 和JXDatePicker

工具版本兼容问题

步骤 1 : 练习-增加
步骤 2 : 答案-增加
步骤 3 : 练习-删除
步骤 4 : 答案-删除
步骤 5 : 练习-编辑
步骤 6 : 答案-编辑
步骤 7 : 练习-修改
步骤 8 : 答案-修改
步骤 9 : 练习-使用按钮分页
步骤 10 : 答案-使用按钮分页
步骤 11 : 练习-使用下拉框分页
步骤 12 : 答案-使用下拉框分页

步骤 1 :

练习-增加

edit 顶折

纠问

姿势不对,事倍功半! 点击查看做练习的正确姿势

点击增加按钮，出现一个JDialog，在JDialog中进行增加

步骤 2 :

答案-增加

edit 顶折

纠问

在查看答案前，尽量先自己完成，碰到问题再来查看答案，收获会更多

查看本答案会花费4个积分，您目前总共有点积分。查看相同答案不会花费额外积分。积分增加办法或者一次性购买JAVA 中级总计0个答案 (总共需要0积分)

账号未激活账号未激活，功能受限。请点击激活

本视频是解读性视频，所以希望您已经看过了本答案的内容，带着疑问来观看，这样收获才多。不建议一开始就观看视频

6分27秒本视频采用html5方式播放，如无法正常播放，请将浏览器升级至最新版本，推荐火狐，chrome，360浏览器。如果装有迅雷，播放视频呈现直接下载状态，请调整迅雷系统设置-基本设置-启动-监视全部浏览器 (去掉这个选项)。 chrome 的视频下载插件会影响播放，如 IDM 等，请关闭或者切换其他浏览器

1.0 原速 1.25 倍速 1.5 倍速 1.75 倍速

1. 首先把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
2. 设计一个静态内部类 AddDialog用于显示增加的界面
3. 在AddDialog中点击提交按钮后，进行为空和数字判断，然后通过dao提交到数据库
4. 隐藏这个AddDialog，并刷新table中的数据

代码行数较多，请点击查看

package gui;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

import charactor.Hero;
import jdbc.HeroDAO;

public class TestGUI {
	//把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
	static HeroTableModel htm = new HeroTableModel();
	static JTable t = new JTable(htm);

	public static void main(String[] args) {

		final JFrame f = new JFrame("LoL");
		f.setSize(400, 300);
		f.setLocation(200, 200);
		f.setLayout(new BorderLayout());

		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

		t.getSelectionModel().setSelectionInterval(0, 0);

		JPanel pOperation = new JPanel();

		JButton bAdd = new JButton("增加");
		pOperation.add(bAdd);

		bAdd.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {
				new AddDialog(f).setVisible(true);
			}
		});

		JScrollPane sp = new JScrollPane(t);

		f.add(sp, BorderLayout.CENTER);
		f.add(pOperation, BorderLayout.SOUTH);

		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		f.setVisible(true);
	}
	
	static class AddDialog extends JDialog{
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");
		
		JTextField tfName =new JTextField();
		JTextField tfHp =new JTextField();
		
		JButton bSubmit =new JButton("提交");
		
		AddDialog(JFrame f){
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);
			
			JPanel pInput= new JPanel();
			JPanel pSubmit= new JPanel();
			
			pInput.setLayout(new GridLayout(2, 2,gap,gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);
			
			pSubmit.add(bSubmit);
			
			pInput.setBounds(50,20,200,100);
			pSubmit.setBounds(0,130,300,150);
			
			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener(){

				@Override
				public void actionPerformed(ActionEvent e) {
					
					if(checkEmpty(tfName, "名称")){
						if(checkNumber(tfHp, "hp")){
						
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());
							
							Hero h = new Hero();
							h.name = name;
							h.hp = hp;
							
							new HeroDAO().add(h);
							
							JOptionPane.showMessageDialog(f, "提交成功 ");
							
							AddDialog.this.setVisible(false);
							updateTable();
						}
					}
					
				}
			});
			
		}
	}
	
	public static void updateTable(){
		htm.heros = new HeroDAO().list();
		t.updateUI();
		if(!htm.heros.isEmpty())
			t.getSelectionModel().setSelectionInterval(0, 0);
	}
	
	private static boolean checkEmpty(JTextField tf, String msg) {
        String value = tf.getText();
        if(0==value.length()){
            JOptionPane.showMessageDialog(null,msg + " 不能为空");
            tf.grabFocus();
            return false;
        }
        return true;
    }
	private static boolean checkNumber(JTextField tf, String msg) {
		String value = tf.getText();
		if(0==value.length()){
			JOptionPane.showMessageDialog(null,msg + " 不能为空");
			tf.grabFocus();
			return false;
		}
		try {
			Integer.parseInt(value);
		} catch (NumberFormatException e) {
			JOptionPane.showMessageDialog(null,msg + " 只能是整数");
			tf.grabFocus();
			return false;
		}
		
		return true;
	}
}

步骤 3 :

练习-删除

edit 顶折

纠问

姿势不对,事倍功半! 点击查看做练习的正确姿势

提供一个删除按钮，点击删除按钮之后，删除选中的行，并且刷新table中的数据，然后再默认选中第一行。

如果点击删除的时候，没有任何行被选中，则提示“删除前应该选中一行”

步骤 4 :

答案-删除

edit 顶折

纠问

在查看答案前，尽量先自己完成，碰到问题再来查看答案，收获会更多

查看本答案会花费3个积分，您目前总共有点积分。查看相同答案不会花费额外积分。积分增加办法或者一次性购买JAVA 中级总计0个答案 (总共需要0积分)

账号未激活账号未激活，功能受限。请点击激活

本视频是解读性视频，所以希望您已经看过了本答案的内容，带着疑问来观看，这样收获才多。不建议一开始就观看视频

5分13秒本视频采用html5方式播放，如无法正常播放，请将浏览器升级至最新版本，推荐火狐，chrome，360浏览器。如果装有迅雷，播放视频呈现直接下载状态，请调整迅雷系统设置-基本设置-启动-监视全部浏览器 (去掉这个选项)。 chrome 的视频下载插件会影响播放，如 IDM 等，请关闭或者切换其他浏览器

1.0 原速 1.25 倍速 1.5 倍速 1.75 倍速

代码行数较多，请点击查看

package gui;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

import charactor.Hero;
import jdbc.HeroDAO;

public class TestGUI {
	//把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
	static HeroTableModel htm = new HeroTableModel();
	static JTable t = new JTable(htm);

	public static void main(String[] args) {

		final JFrame f = new JFrame("LoL");
		f.setSize(400, 300);
		f.setLocation(200, 200);
		f.setLayout(new BorderLayout());

		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

		t.getSelectionModel().setSelectionInterval(0, 0);

		JPanel pOperation = new JPanel();

		JButton bAdd = new JButton("增加");
		JButton bDelete = new JButton("删除");
		pOperation.add(bAdd);
		pOperation.add(bDelete);

		bAdd.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {
				new AddDialog(f).setVisible(true);
			}
		});
		bDelete.addActionListener(new ActionListener() {
			
			@Override
			public void actionPerformed(ActionEvent e) {

				//判断是否选中
				int index = t.getSelectedRow();
				if(-1==index){
					JOptionPane.showMessageDialog(f, "删除前需要先选中一行");
					return;
				}
				
				//进行确认是否要删除
				if(JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？"))
					return;
				
				//获取id
				Hero hero = htm.heros.get(index);
				int id =hero.id;
				
				//删除
				new HeroDAO().delete(id);
				
				//更新table
				updateTable();
				
			}
		});

		JScrollPane sp = new JScrollPane(t);

		f.add(sp, BorderLayout.CENTER);
		f.add(pOperation, BorderLayout.SOUTH);

		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		f.setVisible(true);
	}
	
	static class AddDialog extends JDialog{
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");
		
		JTextField tfName =new JTextField();
		JTextField tfHp =new JTextField();
		
		JButton bSubmit =new JButton("提交");
		
		AddDialog(JFrame f){
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);
			
			JPanel pInput= new JPanel();
			JPanel pSubmit= new JPanel();
			
			pInput.setLayout(new GridLayout(2, 2,gap,gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);
			
			pSubmit.add(bSubmit);
			
			pInput.setBounds(50,20,200,100);
			pSubmit.setBounds(0,130,300,150);
			
			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener(){

				@Override
				public void actionPerformed(ActionEvent e) {
					
					if(checkEmpty(tfName, "名称")){
						if(checkNumber(tfHp, "hp")){
						
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());
							
							Hero h = new Hero();
							h.name = name;
							h.hp = hp;
							
							new HeroDAO().add(h);
							
							JOptionPane.showMessageDialog(f, "提交成功 ");
							
							AddDialog.this.setVisible(false);
							updateTable();
						}
					}
					
				}
			});
			
		}
	}
	
	public static void updateTable(){
		htm.heros = new HeroDAO().list();
		t.updateUI();
		if(!htm.heros.isEmpty())
			t.getSelectionModel().setSelectionInterval(0, 0);
	}
	
	private static boolean checkEmpty(JTextField tf, String msg) {
        String value = tf.getText();
        if(0==value.length()){
            JOptionPane.showMessageDialog(null,msg + " 不能为空");
            tf.grabFocus();
            return false;
        }
        return true;
    }
	private static boolean checkNumber(JTextField tf, String msg) {
		String value = tf.getText();
		if(0==value.length()){
			JOptionPane.showMessageDialog(null,msg + " 不能为空");
			tf.grabFocus();
			return false;
		}
		try {
			Integer.parseInt(value);
		} catch (NumberFormatException e) {
			JOptionPane.showMessageDialog(null,msg + " 只能是整数");
			tf.grabFocus();
			return false;
		}
		
		return true;
	}
}

步骤 5 :

练习-编辑

edit 顶折

纠问

姿势不对,事倍功半! 点击查看做练习的正确姿势

提供一个编辑按钮，点击的时候，弹出一个JDialog，显示选中的数据，并且能够修改。

如果点击的时候，没有选中任意一行，则提示 "编辑前请选中一行数据"

步骤 6 :

答案-编辑

edit 顶折

纠问

在查看答案前，尽量先自己完成，碰到问题再来查看答案，收获会更多

查看本答案会花费4个积分，您目前总共有点积分。查看相同答案不会花费额外积分。积分增加办法或者一次性购买JAVA 中级总计0个答案 (总共需要0积分)

账号未激活账号未激活，功能受限。请点击激活

本视频是解读性视频，所以希望您已经看过了本答案的内容，带着疑问来观看，这样收获才多。不建议一开始就观看视频

4分23秒本视频采用html5方式播放，如无法正常播放，请将浏览器升级至最新版本，推荐火狐，chrome，360浏览器。如果装有迅雷，播放视频呈现直接下载状态，请调整迅雷系统设置-基本设置-启动-监视全部浏览器 (去掉这个选项)。 chrome 的视频下载插件会影响播放，如 IDM 等，请关闭或者切换其他浏览器

1.0 原速 1.25 倍速 1.5 倍速 1.75 倍速

代码行数较多，请点击查看

package gui;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

import charactor.Hero;
import jdbc.HeroDAO;

public class TestGUI {
	// 把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
	static HeroTableModel htm = new HeroTableModel();
	static JTable t = new JTable(htm);

	public static void main(String[] args) {

		final JFrame f = new JFrame("LoL");
		f.setSize(400, 300);
		f.setLocation(200, 200);
		f.setLayout(new BorderLayout());

		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

		t.getSelectionModel().setSelectionInterval(0, 0);

		JPanel pOperation = new JPanel();

		JButton bAdd = new JButton("增加");
		JButton bDelete = new JButton("删除");
		JButton bEdit = new JButton("编辑");
		pOperation.add(bAdd);
		pOperation.add(bDelete);
		pOperation.add(bEdit);

		bEdit.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {
				// 判断是否选中
				int index = t.getSelectedRow();
				if (-1 == index) {
					JOptionPane.showMessageDialog(f, "编辑前需要先选中一行");
					return;
				}

				// 获取选中的对象
				Hero hero = htm.heros.get(index);

				// 显示编辑Dialog

				EditDialog ed = new EditDialog(f);
				ed.tfName.setText(hero.name);
				ed.tfHp.setText(String.valueOf((int) hero.hp));

				ed.setVisible(true);

			}
		});

		bAdd.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {
				new AddDialog(f).setVisible(true);
			}
		});
		bDelete.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {

				// 判断是否选中
				int index = t.getSelectedRow();
				if (-1 == index) {
					JOptionPane.showMessageDialog(f, "删除前需要先选中一行");
					return;
				}

				// 进行确认是否要删除
				if (JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？"))
					return;

				// 获取id
				Hero hero = htm.heros.get(index);
				int id = hero.id;

				// 删除
				new HeroDAO().delete(id);

				// 更新table
				updateTable();

			}
		});

		JScrollPane sp = new JScrollPane(t);

		f.add(sp, BorderLayout.CENTER);
		f.add(pOperation, BorderLayout.SOUTH);

		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		f.setVisible(true);
	}

	static class AddDialog extends JDialog {
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");

		JTextField tfName = new JTextField();
		JTextField tfHp = new JTextField();

		JButton bSubmit = new JButton("提交");

		AddDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);

			pSubmit.add(bSubmit);

			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener() {

				@Override
				public void actionPerformed(ActionEvent e) {

					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {

							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());

							Hero h = new Hero();
							h.name = name;
							h.hp = hp;

							new HeroDAO().add(h);

							JOptionPane.showMessageDialog(f, "提交成功 ");

							AddDialog.this.setVisible(false);
							updateTable();
						}
					}

				}
			});

		}
	}

	public static void updateTable() {
		htm.heros = new HeroDAO().list();
		t.updateUI();
		if (!htm.heros.isEmpty())
			t.getSelectionModel().setSelectionInterval(0, 0);
	}

	private static boolean checkEmpty(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + " 不能为空");
			tf.grabFocus();
			return false;
		}
		return true;
	}

	private static boolean checkNumber(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + " 不能为空");
			tf.grabFocus();
			return false;
		}
		try {
			Integer.parseInt(value);
		} catch (NumberFormatException e) {
			JOptionPane.showMessageDialog(null, msg + " 只能是整数");
			tf.grabFocus();
			return false;
		}

		return true;
	}

	static class EditDialog extends JDialog {
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");

		JTextField tfName = new JTextField();
		JTextField tfHp = new JTextField();

		JButton bSubmit = new JButton("提交");

		EditDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);

			pSubmit.add(bSubmit);

			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
		}
	}
}

步骤 7 :

练习-修改

edit 顶折

纠问

姿势不对,事倍功半! 点击查看做练习的正确姿势

接着练习-编辑继续完整修改的功能。点击修改，首选判断数据是否正确，是否为空，是否为数字等。通过校验后，把数据保存到数据库，然后刷新table中的数据，并且选中第一条。

步骤 8 :

答案-修改

edit 顶折

纠问

在查看答案前，尽量先自己完成，碰到问题再来查看答案，收获会更多

查看本答案会花费3个积分，您目前总共有点积分。查看相同答案不会花费额外积分。积分增加办法或者一次性购买JAVA 中级总计0个答案 (总共需要0积分)

账号未激活账号未激活，功能受限。请点击激活

本视频是解读性视频，所以希望您已经看过了本答案的内容，带着疑问来观看，这样收获才多。不建议一开始就观看视频

4分5秒本视频采用html5方式播放，如无法正常播放，请将浏览器升级至最新版本，推荐火狐，chrome，360浏览器。如果装有迅雷，播放视频呈现直接下载状态，请调整迅雷系统设置-基本设置-启动-监视全部浏览器 (去掉这个选项)。 chrome 的视频下载插件会影响播放，如 IDM 等，请关闭或者切换其他浏览器

1.0 原速 1.25 倍速 1.5 倍速 1.75 倍速

代码行数较多，请点击查看

package gui;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

import charactor.Hero;
import jdbc.HeroDAO;

public class TestGUI {
	// 把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
	static HeroTableModel htm = new HeroTableModel();
	static JTable t = new JTable(htm);

	public static void main(String[] args) {

		final JFrame f = new JFrame("LoL");
		f.setSize(400, 300);
		f.setLocation(200, 200);
		f.setLayout(new BorderLayout());

		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);

		t.getSelectionModel().setSelectionInterval(0, 0);

		JPanel pOperation = new JPanel();

		JButton bAdd = new JButton("增加");
		JButton bDelete = new JButton("删除");
		JButton bEdit = new JButton("编辑");
		pOperation.add(bAdd);
		pOperation.add(bDelete);
		pOperation.add(bEdit);

		bEdit.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {
				// 判断是否选中
				int index = t.getSelectedRow();
				if (-1 == index) {
					JOptionPane.showMessageDialog(f, "编辑前需要先选中一行");
					return;
				}

				// 获取选中的对象
				Hero hero = htm.heros.get(index);

				// 显示编辑Dialog

				EditDialog ed = new EditDialog(f);
				ed.tfName.setText(hero.name);
				ed.tfHp.setText(String.valueOf((int) hero.hp));

				ed.setVisible(true);

			}
		});

		bAdd.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {
				new AddDialog(f).setVisible(true);
			}
		});
		bDelete.addActionListener(new ActionListener() {

			@Override
			public void actionPerformed(ActionEvent e) {

				// 判断是否选中
				int index = t.getSelectedRow();
				if (-1 == index) {
					JOptionPane.showMessageDialog(f, "删除前需要先选中一行");
					return;
				}

				// 进行确认是否要删除
				if (JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？"))
					return;

				// 获取id
				Hero hero = htm.heros.get(index);
				int id = hero.id;

				// 删除
				new HeroDAO().delete(id);

				// 更新table
				updateTable();

			}
		});

		JScrollPane sp = new JScrollPane(t);

		f.add(sp, BorderLayout.CENTER);
		f.add(pOperation, BorderLayout.SOUTH);

		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		f.setVisible(true);
	}

	static class AddDialog extends JDialog {
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");

		JTextField tfName = new JTextField();
		JTextField tfHp = new JTextField();

		JButton bSubmit = new JButton("提交");

		AddDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);

			pSubmit.add(bSubmit);

			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener() {

				@Override
				public void actionPerformed(ActionEvent e) {

					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {

							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());

							Hero h = new Hero();
							h.name = name;
							h.hp = hp;

							new HeroDAO().add(h);

							JOptionPane.showMessageDialog(f, "提交成功 ");

							AddDialog.this.setVisible(false);
							updateTable();
						}
					}

				}
			});

		}
	}

	public static void updateTable() {
		htm.heros = new HeroDAO().list();
		t.updateUI();
		if (!htm.heros.isEmpty())
			t.getSelectionModel().setSelectionInterval(0, 0);
	}

	private static boolean checkEmpty(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + " 不能为空");
			tf.grabFocus();
			return false;
		}
		return true;
	}

	private static boolean checkNumber(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + " 不能为空");
			tf.grabFocus();
			return false;
		}
		try {
			Integer.parseInt(value);
		} catch (NumberFormatException e) {
			JOptionPane.showMessageDialog(null, msg + " 只能是整数");
			tf.grabFocus();
			return false;
		}

		return true;
	}

	static class EditDialog extends JDialog {
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");

		JTextField tfName = new JTextField();
		JTextField tfHp = new JTextField();

		JButton bSubmit = new JButton("提交");

		EditDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);

			pSubmit.add(bSubmit);

			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			
			bSubmit.addActionListener(new ActionListener() {
				
				@Override
				public void actionPerformed(ActionEvent e) {
					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {
							
							//获取id
							int index = t.getSelectedRow();
							int id = htm.heros.get(index).id;
							
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());

							Hero h = new Hero();
							h.name = name;
							h.hp = hp;
							h.id= id;
							
							new HeroDAO().update(h);

							JOptionPane.showMessageDialog(f, "提交成功 ");

							EditDialog.this.setVisible(false);
							updateTable();
						}
					}
					
				}
			});
		}
	}
}

步骤 9 :

练习-使用按钮分页

edit 顶折

纠问

姿势不对,事倍功半! 点击查看做练习的正确姿势

在table中仅仅显示10条数据。
在下方出现4个按钮
首页上一页下一页末页

最后一页
最后一页需要注意，如果数据库中的总数能够整除10，那么最后一页就显示10个，否则就显示不到除以10的余数。比如一共是25个，那么最后一页就显示5个。

按钮的状态要求：
如果有下一页的数据，才能点击下一页，否则下一页按钮是不可用的。
通过如下代码设置代码不可用

JButton.setEnable(false)

对首页，上一页和末页也是一样。

步骤 10 :

答案-使用按钮分页

edit 顶折

纠问

在查看答案前，尽量先自己完成，碰到问题再来查看答案，收获会更多

查看本答案会花费5个积分，您目前总共有点积分。查看相同答案不会花费额外积分。积分增加办法或者一次性购买JAVA 中级总计0个答案 (总共需要0积分)

账号未激活账号未激活，功能受限。请点击激活

本视频是解读性视频，所以希望您已经看过了本答案的内容，带着疑问来观看，这样收获才多。不建议一开始就观看视频

17分23秒本视频采用html5方式播放，如无法正常播放，请将浏览器升级至最新版本，推荐火狐，chrome，360浏览器。如果装有迅雷，播放视频呈现直接下载状态，请调整迅雷系统设置-基本设置-启动-监视全部浏览器 (去掉这个选项)。 chrome 的视频下载插件会影响播放，如 IDM 等，请关闭或者切换其他浏览器

1.0 原速 1.25 倍速 1.5 倍速 1.75 倍速

package gui; import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JDialog; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.JTextField; import javax.swing.ListSelectionModel; import charactor.Hero; import jdbc.HeroDAO; public class TestGUI { static HeroTableModel htm = new HeroTableModel(); static JTable t = new JTable(htm); // 把分页按钮放在这里，后面监听器好访问 static JButton bFirst = new JButton("首页"); static JButton bPre = new JButton("上一页"); static JButton bNext = new JButton("下一页"); static JButton bLast = new JButton("末页"); static int number = 10;// 每页显示10个 static int start = 0;// 开始的页码 public static void main(String[] args) { final JFrame f = new JFrame("LoL"); f.setSize(400, 340); f.setLocation(200, 200); t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION); t.getSelectionModel().setSelectionInterval(0, 0); JPanel pOperation = new JPanel(); JButton bAdd = new JButton("增加"); JButton bDelete = new JButton("删除"); JButton bEdit = new JButton("编辑"); pOperation.add(bAdd); pOperation.add(bDelete); pOperation.add(bEdit); JPanel pPage = new JPanel(); pPage.add(bFirst); pPage.add(bPre); pPage.add(bNext); pPage.add(bLast); bEdit.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // 判断是否选中 int index = t.getSelectedRow(); if (-1 == index) { JOptionPane.showMessageDialog(f, "编辑前需要先选中一行"); return; } // 获取选中的对象 Hero hero = htm.heros.get(index); // 显示编辑Dialog EditDialog ed = new EditDialog(f); ed.tfName.setText(hero.name); ed.tfHp.setText(String.valueOf((int) hero.hp)); ed.setVisible(true); } }); bAdd.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { new AddDialog(f).setVisible(true); updateButtonStatus(); } }); bDelete.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // 判断是否选中 int index = t.getSelectedRow(); if (-1 == index) { JOptionPane.showMessageDialog(f, "删除前需要先选中一行"); return; } // 进行确认是否要删除 if (JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？")) return; // 获取id Hero hero = htm.heros.get(index); int id = hero.id; // 删除 new HeroDAO().delete(id); start = 0; // 更新table updateTable(); updateButtonStatus(); } }); addPageListener(); JScrollPane sp = new JScrollPane(t); f.setLayout(null); sp.setBounds(0, 0, 394, 200); pOperation.setBounds(0, 200, 394, 50); pPage.setBounds(0, 250, 394, 200); f.add(sp); f.add(pOperation); f.add(pPage); updateButtonStatus(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setVisible(true); } private static void addPageListener() { bFirst.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start = 0; updateTable(); updateButtonStatus(); } }); bPre.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start -= number; updateTable(); updateButtonStatus(); } }); bNext.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start += number; updateTable(); updateButtonStatus(); } }); bLast.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start = last(); updateTable(); updateButtonStatus(); } }); } private static void updateButtonStatus() { int last = last(); // 是否有上一页 if (0 != start) { bFirst.setEnabled(true); bPre.setEnabled(true); } // 是否是第一页 if (0 == start) { bFirst.setEnabled(false); bPre.setEnabled(false); } // 是否是最后一页 if (start == last) { bLast.setEnabled(false); bNext.setEnabled(false); } // 是否有下一页 if (start < last) { bLast.setEnabled(true); bNext.setEnabled(true); } } static class AddDialog extends JDialog { JLabel lName = new JLabel("名称"); JLabel lHp = new JLabel("血量"); JTextField tfName = new JTextField(); JTextField tfHp = new JTextField(); JButton bSubmit = new JButton("提交"); AddDialog(JFrame f) { super(f); this.setModal(true); int gap = 50; this.setLayout(null); JPanel pInput = new JPanel(); JPanel pSubmit = new JPanel(); pInput.setLayout(new GridLayout(2, 2, gap, gap)); pInput.add(lName); pInput.add(tfName); pInput.add(lHp); pInput.add(tfHp); pSubmit.add(bSubmit); pInput.setBounds(50, 20, 200, 100); pSubmit.setBounds(0, 130, 300, 150); this.add(pInput); this.add(pSubmit); this.setSize(300, 200); this.setLocationRelativeTo(f); bSubmit.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { if (checkEmpty(tfName, "名称")) { if (checkNumber(tfHp, "hp")) { String name = tfName.getText(); int hp = Integer.parseInt(tfHp.getText()); Hero h = new Hero(); h.name = name; h.hp = hp; new HeroDAO().add(h); JOptionPane.showMessageDialog(f, "提交成功 "); AddDialog.this.setVisible(false); start = 0; updateTable(); } } } }); } } public static void updateTable() { htm.heros = new HeroDAO().list(start, number); t.updateUI(); if (!htm.heros.isEmpty()) t.getSelectionModel().setSelectionInterval(0, 0); } private static boolean checkEmpty(JTextField tf, String msg) { String value = tf.getText(); if (0 == value.length()) { JOptionPane.showMessageDialog(null, msg + " 不能为空"); tf.grabFocus(); return false; } return true; } private static boolean checkNumber(JTextField tf, String msg) { String value = tf.getText(); if (0 == value.length()) { JOptionPane.showMessageDialog(null, msg + " 不能为空"); tf.grabFocus(); return false; } try { Integer.parseInt(value); } catch (NumberFormatException e) { JOptionPane.showMessageDialog(null, msg + " 只能是整数"); tf.grabFocus(); return false; } return true; } static class EditDialog extends JDialog { JLabel lName = new JLabel("名称"); JLabel lHp = new JLabel("血量"); JTextField tfName = new JTextField(); JTextField tfHp = new JTextField(); JButton bSubmit = new JButton("提交"); EditDialog(JFrame f) { super(f); this.setModal(true); int gap = 50; this.setLayout(null); JPanel pInput = new JPanel(); JPanel pSubmit = new JPanel(); pInput.setLayout(new GridLayout(2, 2, gap, gap)); pInput.add(lName); pInput.add(tfName); pInput.add(lHp); pInput.add(tfHp); pSubmit.add(bSubmit); pInput.setBounds(50, 20, 200, 100); pSubmit.setBounds(0, 130, 300, 150); this.add(pInput); this.add(pSubmit); this.setSize(300, 200); this.setLocationRelativeTo(f); bSubmit.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { if (checkEmpty(tfName, "名称")) { if (checkNumber(tfHp, "hp")) { // 获取id int index = t.getSelectedRow(); int id = htm.heros.get(index).id; String name = tfName.getText(); int hp = Integer.parseInt(tfHp.getText()); Hero h = new Hero(); h.name = name; h.hp = hp; h.id = id; new HeroDAO().update(h); JOptionPane.showMessageDialog(f, "提交成功 "); EditDialog.this.setVisible(false); updateTable(); } } } }); } } private static int last() { // 最后一页开始的位置 int last; int total = new HeroDAO().getTotal(); // 最后一页要看总是是否能够整除每页显示的数量number if (0 == total % number) { // 假设总数是20，那么最后一页开始的位置就是10 last = total - number; } else { // 假设总数是21，那么最后一页开始的位置就是20 last = total - total % number; } return last; } }

代码行数较多，请点击查看

package gui;
 
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;
 
import charactor.Hero;
import jdbc.HeroDAO;
 
public class TestGUI {
 
    static HeroTableModel htm = new HeroTableModel();
    static JTable t = new JTable(htm);
 
    // 把分页按钮放在这里，后面监听器好访问
    static JButton bFirst = new JButton("首页");
    static JButton bPre = new JButton("上一页");
    static JButton bNext = new JButton("下一页");
    static JButton bLast = new JButton("末页");
 
    static int number = 10;// 每页显示10个
    static int start = 0;// 开始的页码
 
    public static void main(String[] args) {
 
        final JFrame f = new JFrame("LoL");
        f.setSize(400, 340);
        f.setLocation(200, 200);
 
        t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
 
        t.getSelectionModel().setSelectionInterval(0, 0);
 
        JPanel pOperation = new JPanel();
 
        JButton bAdd = new JButton("增加");
        JButton bDelete = new JButton("删除");
        JButton bEdit = new JButton("编辑");
        pOperation.add(bAdd);
        pOperation.add(bDelete);
        pOperation.add(bEdit);
 
        JPanel pPage = new JPanel();
 
        pPage.add(bFirst);
        pPage.add(bPre);
        pPage.add(bNext);
        pPage.add(bLast);
 
        bEdit.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                // 判断是否选中
                int index = t.getSelectedRow();
                if (-1 == index) {
                    JOptionPane.showMessageDialog(f, "编辑前需要先选中一行");
                    return;
                }
 
                // 获取选中的对象
                Hero hero = htm.heros.get(index);
 
                // 显示编辑Dialog
 
                EditDialog ed = new EditDialog(f);
                ed.tfName.setText(hero.name);
                ed.tfHp.setText(String.valueOf((int) hero.hp));
 
                ed.setVisible(true);
 
            }
        });
 
        bAdd.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                new AddDialog(f).setVisible(true);
                updateButtonStatus();
            }
        });
        bDelete.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
 
                // 判断是否选中
                int index = t.getSelectedRow();
                if (-1 == index) {
                    JOptionPane.showMessageDialog(f, "删除前需要先选中一行");
                    return;
                }
 
                // 进行确认是否要删除
                if (JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？"))
                    return;
 
                // 获取id
                Hero hero = htm.heros.get(index);
                int id = hero.id;
 
                // 删除
                new HeroDAO().delete(id);
 
                start = 0;
                // 更新table
                updateTable();
                updateButtonStatus();
 
            }
        });
 
        addPageListener();
 
        JScrollPane sp = new JScrollPane(t);
 
        f.setLayout(null);
        sp.setBounds(0, 0, 394, 200);
        pOperation.setBounds(0, 200, 394, 50);
        pPage.setBounds(0, 250, 394, 200);
        f.add(sp);
        f.add(pOperation);
        f.add(pPage);
        updateButtonStatus();
 
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        f.setVisible(true);
    }
 
    private static void addPageListener() {
 
        bFirst.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start = 0;
                updateTable();
                updateButtonStatus();
            }
        });
        bPre.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start -= number;
                updateTable();
                updateButtonStatus();
            }
        });
        bNext.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start += number;
                updateTable();
                updateButtonStatus();
            }
        });
        bLast.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start = last();
                updateTable();
                updateButtonStatus();
            }
 
        });
 
    }
 
    private static void updateButtonStatus() {
        int last = last();
 
        // 是否有上一页
        if (0 != start) {
            bFirst.setEnabled(true);
            bPre.setEnabled(true);
        }
 
        // 是否是第一页
        if (0 == start) {
            bFirst.setEnabled(false);
            bPre.setEnabled(false);
        }
 
        // 是否是最后一页
        if (start == last) {
            bLast.setEnabled(false);
            bNext.setEnabled(false);
        }
        // 是否有下一页
        if (start < last) {
            bLast.setEnabled(true);
            bNext.setEnabled(true);
        }
 
    }
 
    static class AddDialog extends JDialog {
        JLabel lName = new JLabel("名称");
        JLabel lHp = new JLabel("血量");
 
        JTextField tfName = new JTextField();
        JTextField tfHp = new JTextField();
 
        JButton bSubmit = new JButton("提交");
 
        AddDialog(JFrame f) {
            super(f);
            this.setModal(true);
            int gap = 50;
            this.setLayout(null);
 
            JPanel pInput = new JPanel();
            JPanel pSubmit = new JPanel();
 
            pInput.setLayout(new GridLayout(2, 2, gap, gap));
            pInput.add(lName);
            pInput.add(tfName);
            pInput.add(lHp);
            pInput.add(tfHp);
 
            pSubmit.add(bSubmit);
 
            pInput.setBounds(50, 20, 200, 100);
            pSubmit.setBounds(0, 130, 300, 150);
 
            this.add(pInput);
            this.add(pSubmit);
 
            this.setSize(300, 200);
            this.setLocationRelativeTo(f);
            bSubmit.addActionListener(new ActionListener() {
 
                @Override
                public void actionPerformed(ActionEvent e) {
 
                    if (checkEmpty(tfName, "名称")) {
                        if (checkNumber(tfHp, "hp")) {
 
                            String name = tfName.getText();
                            int hp = Integer.parseInt(tfHp.getText());
 
                            Hero h = new Hero();
                            h.name = name;
                            h.hp = hp;
 
                            new HeroDAO().add(h);
 
                            JOptionPane.showMessageDialog(f, "提交成功 ");
 
                            AddDialog.this.setVisible(false);
                            start = 0;
                            updateTable();
                        }
                    }
                }
            });
        }
    }
 
    public static void updateTable() {
        htm.heros = new HeroDAO().list(start, number);
        t.updateUI();
        if (!htm.heros.isEmpty())
            t.getSelectionModel().setSelectionInterval(0, 0);
    }
 
    private static boolean checkEmpty(JTextField tf, String msg) {
        String value = tf.getText();
        if (0 == value.length()) {
            JOptionPane.showMessageDialog(null, msg + " 不能为空");
            tf.grabFocus();
            return false;
        }
        return true;
    }
 
    private static boolean checkNumber(JTextField tf, String msg) {
        String value = tf.getText();
        if (0 == value.length()) {
            JOptionPane.showMessageDialog(null, msg + " 不能为空");
            tf.grabFocus();
            return false;
        }
        try {
            Integer.parseInt(value);
        } catch (NumberFormatException e) {
            JOptionPane.showMessageDialog(null, msg + " 只能是整数");
            tf.grabFocus();
            return false;
        }
 
        return true;
    }
 
    static class EditDialog extends JDialog {
        JLabel lName = new JLabel("名称");
        JLabel lHp = new JLabel("血量");
 
        JTextField tfName = new JTextField();
        JTextField tfHp = new JTextField();
 
        JButton bSubmit = new JButton("提交");
 
        EditDialog(JFrame f) {
            super(f);
            this.setModal(true);
            int gap = 50;
            this.setLayout(null);
 
            JPanel pInput = new JPanel();
            JPanel pSubmit = new JPanel();
 
            pInput.setLayout(new GridLayout(2, 2, gap, gap));
            pInput.add(lName);
            pInput.add(tfName);
            pInput.add(lHp);
            pInput.add(tfHp);
 
            pSubmit.add(bSubmit);
 
            pInput.setBounds(50, 20, 200, 100);
            pSubmit.setBounds(0, 130, 300, 150);
 
            this.add(pInput);
            this.add(pSubmit);
 
            this.setSize(300, 200);
            this.setLocationRelativeTo(f);
 
            bSubmit.addActionListener(new ActionListener() {
 
                @Override
                public void actionPerformed(ActionEvent e) {
                    if (checkEmpty(tfName, "名称")) {
                        if (checkNumber(tfHp, "hp")) {
 
                            // 获取id
                            int index = t.getSelectedRow();
                            int id = htm.heros.get(index).id;
 
                            String name = tfName.getText();
                            int hp = Integer.parseInt(tfHp.getText());
 
                            Hero h = new Hero();
                            h.name = name;
                            h.hp = hp;
                            h.id = id;
 
                            new HeroDAO().update(h);
 
                            JOptionPane.showMessageDialog(f, "提交成功 ");
 
                            EditDialog.this.setVisible(false);
                            updateTable();
                        }
                    }
 
                }
            });
        }
    }
 
    private static int last() {
        // 最后一页开始的位置
        int last;
 
        int total = new HeroDAO().getTotal();
 
        // 最后一页要看总是是否能够整除每页显示的数量number
 
        if (0 == total % number) {
            // 假设总数是20，那么最后一页开始的位置就是10
            last = total - number;
        } else {
            // 假设总数是21，那么最后一页开始的位置就是20
            last = total - total % number;
        }
        return last;
 
    }
}

步骤 11 :

练习-使用下拉框分页

edit 顶折

纠问

姿势不对,事倍功半! 点击查看做练习的正确姿势

借助下拉框实现下拉框分页

步骤 12 :

答案-使用下拉框分页

edit 顶折

纠问

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1.0 原速 1.25 倍速 1.5 倍速 1.75 倍速

package gui; import java.awt.BorderLayout; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JDialog; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JOptionPane; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.JTextField; import javax.swing.ListSelectionModel; import charactor.Hero; import jdbc.HeroDAO; public class TestGUI { static HeroTableModel htm = new HeroTableModel(); static JTable t = new JTable(htm); // 把分页按钮放在这里，后面监听器好访问 static JButton bFirst = new JButton("首页"); static JButton bPre = new JButton("上一页"); static JButton bNext = new JButton("下一页"); static JButton bLast = new JButton("末页"); static JComboBox<Integer> cb = new JComboBox<>(); static int number = 10;// 每页显示10个 static int start = 0;// 开始的页码 private static boolean cbListenerEnabled = true; public static void main(String[] args) { final JFrame f = new JFrame("LoL"); f.setSize(400, 340); f.setLocation(200, 200); t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION); t.getSelectionModel().setSelectionInterval(0, 0); JPanel pOperation = new JPanel(); JButton bAdd = new JButton("增加"); JButton bDelete = new JButton("删除"); JButton bEdit = new JButton("编辑"); pOperation.add(bAdd); pOperation.add(bDelete); pOperation.add(bEdit); JPanel pPage = new JPanel(); pPage.add(bFirst); pPage.add(bPre); pPage.add(cb); pPage.add(bNext); pPage.add(bLast); bEdit.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // 判断是否选中 int index = t.getSelectedRow(); if (-1 == index) { JOptionPane.showMessageDialog(f, "编辑前需要先选中一行"); return; } // 获取选中的对象 Hero hero = htm.heros.get(index); // 显示编辑Dialog EditDialog ed = new EditDialog(f); ed.tfName.setText(hero.name); ed.tfHp.setText(String.valueOf((int) hero.hp)); ed.setVisible(true); } }); bAdd.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { new AddDialog(f).setVisible(true); updateButtonStatus(); } }); bDelete.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { // 判断是否选中 int index = t.getSelectedRow(); if (-1 == index) { JOptionPane.showMessageDialog(f, "删除前需要先选中一行"); return; } // 进行确认是否要删除 if (JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？")) return; // 获取id Hero hero = htm.heros.get(index); int id = hero.id; // 删除 new HeroDAO().delete(id); // 更新table start = 0; updateTable(); updateButtonStatus(); } }); addPageListener(); cb.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { if(!cbListenerEnabled) return; int currentPage = (int) cb.getSelectedItem(); start = (currentPage-1)*number; updateTable(); updateButtonStatus(); } }); JScrollPane sp = new JScrollPane(t); f.setLayout(null); sp.setBounds(0, 0, 394, 200); pOperation.setBounds(0, 200, 394, 50); pPage.setBounds(0, 250, 394, 200); f.add(sp); f.add(pOperation); f.add(pPage); updateButtonStatus(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.setVisible(true); } private static void addPageListener() { bFirst.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start = 0; updateTable(); updateButtonStatus(); } }); bPre.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start -= number; updateTable(); updateButtonStatus(); } }); bNext.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start += number; updateTable(); updateButtonStatus(); } }); bLast.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { start = last(); updateTable(); updateButtonStatus(); } }); } private static void updateButtonStatus() { int last = last(); // 是否有上一页 if (0 != start) { bFirst.setEnabled(true); bPre.setEnabled(true); } // 是否是第一页 if (0 == start) { bFirst.setEnabled(false); bPre.setEnabled(false); } // 是否是最后一页 if (start == last) { bLast.setEnabled(false); bNext.setEnabled(false); } // 是否有下一页 if (start < last) { bLast.setEnabled(true); bNext.setEnabled(true); } //总共的页数 int pageNumber =last/number+1; cbListenerEnabled = false; cb.removeAllItems(); for (int i = 0; i < pageNumber; i++) { cb.addItem(i+1); } cbListenerEnabled = true; int currentPage = start/number +1; cb.setSelectedItem(currentPage); } static class AddDialog extends JDialog { JLabel lName = new JLabel("名称"); JLabel lHp = new JLabel("血量"); JTextField tfName = new JTextField(); JTextField tfHp = new JTextField(); JButton bSubmit = new JButton("提交"); AddDialog(JFrame f) { super(f); this.setModal(true); int gap = 50; this.setLayout(null); JPanel pInput = new JPanel(); JPanel pSubmit = new JPanel(); pInput.setLayout(new GridLayout(2, 2, gap, gap)); pInput.add(lName); pInput.add(tfName); pInput.add(lHp); pInput.add(tfHp); pSubmit.add(bSubmit); pInput.setBounds(50, 20, 200, 100); pSubmit.setBounds(0, 130, 300, 150); this.add(pInput); this.add(pSubmit); this.setSize(300, 200); this.setLocationRelativeTo(f); bSubmit.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { if (checkEmpty(tfName, "名称")) { if (checkNumber(tfHp, "hp")) { String name = tfName.getText(); int hp = Integer.parseInt(tfHp.getText()); Hero h = new Hero(); h.name = name; h.hp = hp; new HeroDAO().add(h); JOptionPane.showMessageDialog(f, "提交成功 "); AddDialog.this.setVisible(false); start = 0; updateTable(); } } } }); } } public static void updateTable() { htm.heros = new HeroDAO().list(start, number); t.updateUI(); if (!htm.heros.isEmpty()) t.getSelectionModel().setSelectionInterval(0, 0); } private static boolean checkEmpty(JTextField tf, String msg) { String value = tf.getText(); if (0 == value.length()) { JOptionPane.showMessageDialog(null, msg + " 不能为空"); tf.grabFocus(); return false; } return true; } private static boolean checkNumber(JTextField tf, String msg) { String value = tf.getText(); if (0 == value.length()) { JOptionPane.showMessageDialog(null, msg + " 不能为空"); tf.grabFocus(); return false; } try { Integer.parseInt(value); } catch (NumberFormatException e) { JOptionPane.showMessageDialog(null, msg + " 只能是整数"); tf.grabFocus(); return false; } return true; } static class EditDialog extends JDialog { JLabel lName = new JLabel("名称"); JLabel lHp = new JLabel("血量"); JTextField tfName = new JTextField(); JTextField tfHp = new JTextField(); JButton bSubmit = new JButton("提交"); EditDialog(JFrame f) { super(f); this.setModal(true); int gap = 50; this.setLayout(null); JPanel pInput = new JPanel(); JPanel pSubmit = new JPanel(); pInput.setLayout(new GridLayout(2, 2, gap, gap)); pInput.add(lName); pInput.add(tfName); pInput.add(lHp); pInput.add(tfHp); pSubmit.add(bSubmit); pInput.setBounds(50, 20, 200, 100); pSubmit.setBounds(0, 130, 300, 150); this.add(pInput); this.add(pSubmit); this.setSize(300, 200); this.setLocationRelativeTo(f); bSubmit.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { if (checkEmpty(tfName, "名称")) { if (checkNumber(tfHp, "hp")) { // 获取id int index = t.getSelectedRow(); int id = htm.heros.get(index).id; String name = tfName.getText(); int hp = Integer.parseInt(tfHp.getText()); Hero h = new Hero(); h.name = name; h.hp = hp; h.id = id; new HeroDAO().update(h); JOptionPane.showMessageDialog(f, "提交成功 "); EditDialog.this.setVisible(false); updateTable(); } } } }); } } private static int last() { // 最后一页开始的位置 int last; int total = new HeroDAO().getTotal(); // 最后一页要看总是是否能够整除每页显示的数量number if (0 == total % number) { // 假设总数是20，那么最后一页开始的位置就是10 last = total - number; } else { // 假设总数是21，那么最后一页开始的位置就是20 last = total - total % number; } return last; } }

代码行数较多，请点击查看

package gui;
 
import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;
 
import charactor.Hero;
import jdbc.HeroDAO;
 
public class TestGUI {
 
    static HeroTableModel htm = new HeroTableModel();
    static JTable t = new JTable(htm);
 
    // 把分页按钮放在这里，后面监听器好访问
    static JButton bFirst = new JButton("首页");
    static JButton bPre = new JButton("上一页");
    static JButton bNext = new JButton("下一页");
    static JButton bLast = new JButton("末页");
    static JComboBox<Integer> cb = new JComboBox<>();
 
    static int number = 10;// 每页显示10个
    static int start = 0;// 开始的页码
    private static boolean cbListenerEnabled = true;
 
    public static void main(String[] args) {
 
        final JFrame f = new JFrame("LoL");
        f.setSize(400, 340);
        f.setLocation(200, 200);
 
        t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
 
        t.getSelectionModel().setSelectionInterval(0, 0);
 
        JPanel pOperation = new JPanel();
 
        JButton bAdd = new JButton("增加");
        JButton bDelete = new JButton("删除");
        JButton bEdit = new JButton("编辑");
        pOperation.add(bAdd);
        pOperation.add(bDelete);
        pOperation.add(bEdit);
 
        JPanel pPage = new JPanel();
 
        pPage.add(bFirst);
        pPage.add(bPre);
        pPage.add(cb);
         
        pPage.add(bNext);
        pPage.add(bLast);
 
        bEdit.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                // 判断是否选中
                int index = t.getSelectedRow();
                if (-1 == index) {
                    JOptionPane.showMessageDialog(f, "编辑前需要先选中一行");
                    return;
                }
 
                // 获取选中的对象
                Hero hero = htm.heros.get(index);
 
                // 显示编辑Dialog
 
                EditDialog ed = new EditDialog(f);
                ed.tfName.setText(hero.name);
                ed.tfHp.setText(String.valueOf((int) hero.hp));
 
                ed.setVisible(true);
 
            }
        });
 
        bAdd.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                new AddDialog(f).setVisible(true);
                
                updateButtonStatus();
            }
        });
        bDelete.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
 
                // 判断是否选中
                int index = t.getSelectedRow();
                if (-1 == index) {
                    JOptionPane.showMessageDialog(f, "删除前需要先选中一行");
                    return;
                }
 
                // 进行确认是否要删除
                if (JOptionPane.OK_OPTION != JOptionPane.showConfirmDialog(f, "确认要删除？"))
                    return;
 
                // 获取id
                Hero hero = htm.heros.get(index);
                int id = hero.id;
 
                // 删除
                new HeroDAO().delete(id);
 
                // 更新table
                start = 0;
                updateTable();
                updateButtonStatus();
 
            }
        });
 
        addPageListener();
         
        cb.addActionListener(new ActionListener() {
             
            @Override
            public void actionPerformed(ActionEvent e) {
                if(!cbListenerEnabled)
                    return;
                 
                int currentPage = (int) cb.getSelectedItem();
                start = (currentPage-1)*number;
                updateTable();
                updateButtonStatus();
                 
            }
        });
 
        JScrollPane sp = new JScrollPane(t);
 
        f.setLayout(null);
        sp.setBounds(0, 0, 394, 200);
        pOperation.setBounds(0, 200, 394, 50);
        pPage.setBounds(0, 250, 394, 200);
        f.add(sp);
        f.add(pOperation);
        f.add(pPage);
        updateButtonStatus();
 
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
 
        f.setVisible(true);
    }
 
    private static void addPageListener() {
 
        bFirst.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start = 0;
                updateTable();
                updateButtonStatus();
            }
        });
        bPre.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start -= number;
                updateTable();
                updateButtonStatus();
            }
        });
        bNext.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                start += number;
                updateTable();
                updateButtonStatus();
            }
        });
        bLast.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                 
                start = last();
 
                updateTable();
                 
                updateButtonStatus();
                 
            }
 
        });
 
    }
 
    private static void updateButtonStatus() {
        int last = last();
 
        // 是否有上一页
        if (0 != start) {
            bFirst.setEnabled(true);
            bPre.setEnabled(true);
        }
 
        // 是否是第一页
        if (0 == start) {
            bFirst.setEnabled(false);
            bPre.setEnabled(false);
        }
 
        // 是否是最后一页
        if (start == last) {
            bLast.setEnabled(false);
            bNext.setEnabled(false);
        }
        // 是否有下一页
        if (start < last) {
            bLast.setEnabled(true);
            bNext.setEnabled(true);
        }
         
        //总共的页数
        int pageNumber =last/number+1;
        cbListenerEnabled = false;
        cb.removeAllItems();
 
        for (int i = 0; i < pageNumber; i++) {
 
            cb.addItem(i+1);
        }
        cbListenerEnabled = true;
         
        int currentPage = start/number +1;
        cb.setSelectedItem(currentPage);
 
    }
 
    static class AddDialog extends JDialog {
        JLabel lName = new JLabel("名称");
        JLabel lHp = new JLabel("血量");
 
        JTextField tfName = new JTextField();
        JTextField tfHp = new JTextField();
 
        JButton bSubmit = new JButton("提交");
 
        AddDialog(JFrame f) {
            super(f);
            this.setModal(true);
            int gap = 50;
            this.setLayout(null);
 
            JPanel pInput = new JPanel();
            JPanel pSubmit = new JPanel();
 
            pInput.setLayout(new GridLayout(2, 2, gap, gap));
            pInput.add(lName);
            pInput.add(tfName);
            pInput.add(lHp);
            pInput.add(tfHp);
 
            pSubmit.add(bSubmit);
 
            pInput.setBounds(50, 20, 200, 100);
            pSubmit.setBounds(0, 130, 300, 150);
 
            this.add(pInput);
            this.add(pSubmit);
 
            this.setSize(300, 200);
            this.setLocationRelativeTo(f);
            bSubmit.addActionListener(new ActionListener() {
 
                @Override
                public void actionPerformed(ActionEvent e) {
 
                    if (checkEmpty(tfName, "名称")) {
                        if (checkNumber(tfHp, "hp")) {
 
                            String name = tfName.getText();
                            int hp = Integer.parseInt(tfHp.getText());
 
                            Hero h = new Hero();
                            h.name = name;
                            h.hp = hp;
 
                            new HeroDAO().add(h);
 
                            JOptionPane.showMessageDialog(f, "提交成功 ");
 
                            AddDialog.this.setVisible(false);
                            start = 0;
                            updateTable();
                        }
                    }
 
                }
            });
 
        }
    }
 
    public static void updateTable() {
        htm.heros = new HeroDAO().list(start, number);
        t.updateUI();
        if (!htm.heros.isEmpty())
            t.getSelectionModel().setSelectionInterval(0, 0);
    }
 
    private static boolean checkEmpty(JTextField tf, String msg) {
        String value = tf.getText();
        if (0 == value.length()) {
            JOptionPane.showMessageDialog(null, msg + " 不能为空");
            tf.grabFocus();
            return false;
        }
        return true;
    }
 
    private static boolean checkNumber(JTextField tf, String msg) {
        String value = tf.getText();
        if (0 == value.length()) {
            JOptionPane.showMessageDialog(null, msg + " 不能为空");
            tf.grabFocus();
            return false;
        }
        try {
            Integer.parseInt(value);
        } catch (NumberFormatException e) {
            JOptionPane.showMessageDialog(null, msg + " 只能是整数");
            tf.grabFocus();
            return false;
        }
 
        return true;
    }
 
    static class EditDialog extends JDialog {
        JLabel lName = new JLabel("名称");
        JLabel lHp = new JLabel("血量");
 
        JTextField tfName = new JTextField();
        JTextField tfHp = new JTextField();
 
        JButton bSubmit = new JButton("提交");
 
        EditDialog(JFrame f) {
            super(f);
            this.setModal(true);
            int gap = 50;
            this.setLayout(null);
 
            JPanel pInput = new JPanel();
            JPanel pSubmit = new JPanel();
 
            pInput.setLayout(new GridLayout(2, 2, gap, gap));
            pInput.add(lName);
            pInput.add(tfName);
            pInput.add(lHp);
            pInput.add(tfHp);
 
            pSubmit.add(bSubmit);
 
            pInput.setBounds(50, 20, 200, 100);
            pSubmit.setBounds(0, 130, 300, 150);
 
            this.add(pInput);
            this.add(pSubmit);
 
            this.setSize(300, 200);
            this.setLocationRelativeTo(f);
 
            bSubmit.addActionListener(new ActionListener() {
 
                @Override
                public void actionPerformed(ActionEvent e) {
                    if (checkEmpty(tfName, "名称")) {
                        if (checkNumber(tfHp, "hp")) {
 
                            // 获取id
                            int index = t.getSelectedRow();
                            int id = htm.heros.get(index).id;
 
                            String name = tfName.getText();
                            int hp = Integer.parseInt(tfHp.getText());
 
                            Hero h = new Hero();
                            h.name = name;
                            h.hp = hp;
                            h.id = id;
 
                            new HeroDAO().update(h);
 
                            JOptionPane.showMessageDialog(f, "提交成功 ");
 
                            EditDialog.this.setVisible(false);
                            updateTable();
                        }
                    }
 
                }
            });
        }
    }
 
    private static int last() {
        // 最后一页开始的位置
        int last;
 
        int total = new HeroDAO().getTotal();
 
        // 最后一页要看总是是否能够整除每页显示的数量number
 
        if (0 == total % number) {
            // 假设总数是20，那么最后一页开始的位置就是10
            last = total - number;
        } else {
            // 假设总数是21，那么最后一页开始的位置就是20
            last = total - total % number;
        }
        return last;
 
    }
}

图形界面系列教材（十一）- 两种Swing下的日期控件 DatePicker 和JXDatePicker

图形界面系列教材（十三）- Swing中的线程

HOW2J公众号，关注后实时获知最新的教程和优惠活动，谢谢。

问答区域

2023-09-05 综合练习，完整代码

旧时亭台阁

关于 JAVA 中级-图形界面-表格综合练习的提问

写得脑阔疼

// ============================================ 启动类 =================================
import character.Hero;
import jdbc.HeroDAO;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ItemEvent;
import java.util.function.Consumer;

public class TestGUI {
    public static void main(String[] args) {
        // 窗体
        JFrame frame = new JFrame("LOL");
        frame.setLocation(1000, 500);
        frame.setSize(800, 600);
        frame.setLayout(new BorderLayout());

        // 上下两个主要面板
        JScrollPane centerPanel = new JScrollPane();
        JPanel bottomPanel = new JPanel(new BorderLayout());
        frame.add(centerPanel, BorderLayout.CENTER);
        frame.add(bottomPanel, BorderLayout.SOUTH);

        // 上面板，存放表格组件
        HeroTableModel heroTableModel = new HeroTableModel(10);         // TODO：分页大小设置
        JTable table = new JTable(heroTableModel);
        centerPanel.setViewportView(table);

        // 下面板，增删查改、分页
        JPanel editPanel = new JPanel();
        JPanel pagePanel = new JPanel();
        bottomPanel.add(editPanel, BorderLayout.NORTH);
        bottomPanel.add(pagePanel, BorderLayout.SOUTH);

        // 下方的，增删改 按钮
        JButton addBtn = (JButton) editPanel.add(new JButton("增加"));
        JButton delBtn = (JButton) editPanel.add(new JButton("删除"));
        JButton editBtn = (JButton) editPanel.add(new JButton("编辑"));

        // 下方的，分页按钮
        JButton firstPageBtn = (JButton) pagePanel.add(new JButton("首页"));
        JButton prevPageBtn = (JButton) pagePanel.add(new JButton("上一页"));
        JComboBox<Integer> comboBox = (JComboBox<Integer>) pagePanel.add(new JComboBox<>());
        JButton nextPageBtn = (JButton) pagePanel.add(new JButton("下一页"));
        JButton lastPageBtn = (JButton) pagePanel.add(new JButton("末页"));


        // 增删改 事件绑定
        addBtn.addActionListener(e -> {
            Hero hero = new Hero();
            generateDialog(frame, "添加英雄", hero, dialog -> {
                new HeroDAO().add(hero);
                JOptionPane.showMessageDialog(dialog, "新增成功！");

                heroTableModel.updateDataSource();          // 更新数据源
                table.updateUI();                           // 重新渲染表格
            });
        });
        editBtn.addActionListener(e -> {
            // 获取当前选择的行数据
            if (table.getSelectedRows().length != 1) {
                JOptionPane.showMessageDialog(frame, "需要选择一条数据进行编辑！！！");
                return;
            }
            Hero hero = heroTableModel.getRowData(table.getSelectedRow());
            generateDialog(frame, "编辑英雄", hero, dialog -> {
                new HeroDAO().update(hero);
                JOptionPane.showMessageDialog(dialog, "修改成功！");
                dialog.setVisible(false);

                heroTableModel.updateDataSource();          // 更新数据源
                table.updateUI();                           // 重新渲染表格
            });
        });
        delBtn.addActionListener(e -> {
            int[] selectedRows = table.getSelectedRows();
            if (0 == selectedRows.length) {
                JOptionPane.showMessageDialog(frame, "删除前应该至少选中一行！！！");
                return;
            }
            int opt = JOptionPane.showConfirmDialog(frame, "确认要删除");
            if (JOptionPane.OK_OPTION == opt) {
                StringBuilder sb = new StringBuilder();
                for (int selectedRow : selectedRows) {
                    int id = heroTableModel.getRowData(selectedRow).getId();
                    new HeroDAO().delete(id);
                    sb.append(id).append(",");
                }
                sb.deleteCharAt(sb.length() - 1);
                JOptionPane.showMessageDialog(frame, "成功删除 id 为 [ " + sb + " ] 的数据！！！");

                heroTableModel.updateDataSource();          // 更新数据源
                table.updateUI();                           // 重新渲染表格
            }
        });


        // 分页  事件绑定
        heroTableModel.injectPagerHelper(firstPageBtn,  prevPageBtn, comboBox, nextPageBtn, lastPageBtn);
        firstPageBtn.addActionListener(e -> {
            heroTableModel.setCurrentPageNum(0);
            table.updateUI();
        });
        prevPageBtn.addActionListener(e -> {
            heroTableModel.setCurrentPageNum(heroTableModel.getCurrentPageNum() - 1);
            table.updateUI();
        });
        nextPageBtn.addActionListener(e -> {
            heroTableModel.setCurrentPageNum(heroTableModel.getCurrentPageNum() + 1);
            table.updateUI();
        });
        lastPageBtn.addActionListener(e -> {
            heroTableModel.setCurrentPageNum(heroTableModel.getMaxPageNum());
            table.updateUI();
        });
        comboBox.addItemListener(a -> {
            if (a.getStateChange() == ItemEvent.SELECTED) {
                heroTableModel.setCurrentPageNum((Integer) a.getItem() - 1);
                table.updateUI();
            }
        });


        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }


    // 增加/编辑 英雄界面
    private static void generateDialog(JFrame frame, String title, Hero hero, Consumer<JDialog> consumer) {
        // 对话框
        JDialog dialog = new JDialog(frame, title, true);
        dialog.setBounds(1200, 700, 200, 150);
        dialog.setResizable(false);
        dialog.setLayout(new FlowLayout());

        // 组件
        dialog.add(new JLabel("名称："));
        JTextField textFieldOfName = (JTextField) dialog.add(new JTextField(hero.getName()));
        textFieldOfName.setPreferredSize(new Dimension(120, 30));
        dialog.add(new JLabel("血量："));
        JTextField textFieldOfHp = (JTextField) dialog.add(new JTextField(String.valueOf(hero.getHp())));
        textFieldOfHp.setPreferredSize(new Dimension(120, 30));

        // 提交按钮
        JButton button = (JButton) dialog.add(new JButton("提交"));
        // 提交按钮，响应事件
        button.addActionListener(e -> {
            // 校验输入
            String name = textFieldOfName.getText();
            if (null == name || name.isEmpty()) {
                JOptionPane.showMessageDialog(dialog, "名称为空！！！");
                return;
            }
            String hpStr = textFieldOfHp.getText();
            if (null == hpStr || hpStr.isEmpty()) {
                JOptionPane.showMessageDialog(dialog, "血量为空！！！");
                return;
            }
            float hp;
            try {
                hp = Float.parseFloat(hpStr);
            } catch (Exception e2) {
                JOptionPane.showMessageDialog(dialog, "血量不是数字！！！");
                return;
            }

            hero.setName(name);
            hero.setHp(hp);

            // 行为注入
            consumer.accept(dialog);
        });
        dialog.setVisible(true);
    }


}










// ============================================ 自定义的表格的数据源模型 =================================
import character.Hero;
import jdbc.HeroDAO;

import javax.swing.*;
import javax.swing.table.AbstractTableModel;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.List;
import java.util.stream.Collectors;

public class HeroTableModel extends AbstractTableModel {

    private final HeroDAO dao;

    private final int[] pageStat;

    private JButton[] pageHelper;
    private JComboBox<Integer> pageComboBox;

    private final List<String> headers;

    private List<Hero> heroes;

    public HeroTableModel(int pageSize) {
        dao = new HeroDAO();

        Field[] fields = Hero.class.getDeclaredFields();
        headers = Arrays.stream(fields).map(Field::getName).collect(Collectors.toList());

        pageStat = new int[3];        // 页大小，当前页数，最大页数
        setPageSize(pageSize);
    }

    // 更新当前页的数据
    public void updateDataSource() {
        calculateMaxPageNum();
        int cur  = getCurrentPageNum(), size = getPageSize();
        heroes = dao.list(cur * size, size);
    }

    // 获取指定下标的行数据
    public Hero getRowData(int rowIndex) {
        return heroes.get(rowIndex);
    }

    // 注入分页器
    public void injectPagerHelper(JButton first, JButton prev, JComboBox<Integer> comboBox, JButton next, JButton last) {
        pageHelper = new JButton[]{first, prev, next, last};
        pageComboBox = comboBox;
        updatePageHelperStatus();
    }

    public int getCurrentPageNum() {
        return pageStat[1];
    }

    public void setCurrentPageNum(int cur) {
        pageStat[1] = cur;
        updateDataSource();
    }

    public int getPageSize() {
        return pageStat[0];
    }

    public void setPageSize(int pageSize) {
        pageStat[0] = pageSize;
        updateDataSource();
    }

    public int getMaxPageNum() {
        return pageStat[2];
    }

    private void setMaxPageNum(int max) {
        pageStat[2] = max;
        updatePageHelperStatus();
    }

    // 更新分页器的状态
    private void updatePageHelperStatus() {
        if (null == pageHelper || null == pageComboBox) {
            return;
        }

        for (int i = Math.max(0, pageComboBox.getItemCount()); i <= getMaxPageNum(); i++) {
            pageComboBox.addItem(i + 1);
        }
        pageComboBox.setSelectedIndex(getCurrentPageNum());


        if (getCurrentPageNum() == 0) {
            pageHelper[0].setEnabled(false);
            pageHelper[1].setEnabled(false);
        } else {
            pageHelper[0].setEnabled(true);
            pageHelper[1].setEnabled(true);
        }

        if (getCurrentPageNum() < getMaxPageNum()) {
            pageHelper[2].setEnabled(true);
            pageHelper[3].setEnabled(true);
        } else {
            pageHelper[2].setEnabled(false);
            pageHelper[3].setEnabled(false);
        }
    }

    // 计算并更新最大页数
    private void calculateMaxPageNum() {
        int total = dao.getTotal(), size = getPageSize();
        int max = (total + size - 1) / size - 1;
        setMaxPageNum(max);
    }

    @Override
    public int getRowCount() {
        return heroes.size();
    }

    @Override
    public int getColumnCount() {
        return headers.size();
    }

    @Override
    public String getColumnName(int column) {
        return headers.get(column);
    }

    @Override
    public Object getValueAt(int rowIndex, int columnIndex) {
        Hero h =  heroes.get(rowIndex);

        Field field = Hero.class.getDeclaredFields()[columnIndex];
        field.setAccessible(true);

        try {
            return field.get(h);
        } catch (IllegalAccessException e) {
            throw new RuntimeException(e);
        }
    }
}

1 个答案

CharlieLong
答案时间：2023-10-16

综合练习答案

代码超过 5行，点击查看

package GUI.practice;
/**
 * 表格增删改查的练习，提供增加、修改、删除功能；提供分页按钮、提供下拉框做分页
 */

import JDBC.study.HeroDAO;
import charactor.Hero;
import javax.swing.*;
import java.awt.*;
import java.util.function.Consumer;

import GUI.study.HeroTableModel1;

public class pracTable {

    private static int iTotalHero;
    public static HeroDAO dao=new HeroDAO();
    //设置分页大小
    public static final int countIndex=10;
    public static HeroTableModel1 htm=new HeroTableModel1(countIndex,1);

    public static void main(String[] args) {



        //用DAO的方法获取数据库的内容创建对象

        JFrame f = new JFrame("LoL");
        f.setSize(800, 300);
        f.setLocation(200, 200);
        f.setLayout(new BorderLayout());

        //工具栏面板
        JToolBar jToolBarNorth=new JToolBar();
        jToolBarNorth.setFloatable(false);
        JPanel pToolbarNorth=new JPanel(new FlowLayout(FlowLayout.LEFT));


        JButton bAdd=new JButton("增加");
        JButton bDelete=new JButton("删除");
        JButton bModify=new JButton("编辑");

        jToolBarNorth.add(bAdd);
        jToolBarNorth.add(bDelete);
        jToolBarNorth.add(bModify);
        pToolbarNorth.add(jToolBarNorth);

        //表格面板

        //根据 TableModel来创建 Table
        JTable t = new JTable(htm);
        t.setGridColor(Color.blue);
        // 设置选择模式为 只能选中一行
        t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        // 选中第一行 （基本0）
        t.getSelectionModel().setSelectionInterval(0, 0);

        JScrollPane sp = new JScrollPane(t);

        //分页面板
        JToolBar jToolBarSouth=new JToolBar();
        jToolBarSouth.setFloatable(false);
        JPanel pSouth=new JPanel(new BorderLayout());
        pSouth.setBackground(Color.BLUE);
        GridBagConstraints gdcSouth=new GridBagConstraints();
        // 设置组件填充方式为BOTH
        gdcSouth.fill = GridBagConstraints.BOTH;
        JPanel pStatus=new JPanel(new FlowLayout(FlowLayout.LEFT));
        JPanel pToolbarSouth=new JPanel(new FlowLayout(FlowLayout.RIGHT));

        JButton bPageFirst=new JButton("首页");
        JButton bPageUp=new JButton("上一页");
        JComboBox cb=new JComboBox();
        refreshComboBox(cb);
        cb.setSelectedIndex(0);//默认选0位
        JButton bPageDown=new JButton("下一页");
        JButton bPageLast=new JButton("末页");
        JLabel l=new JLabel("暂未选中条目");

        jToolBarSouth.add(bPageFirst);
        jToolBarSouth.add(bPageUp);
        jToolBarSouth.add(cb);
        jToolBarSouth.add(bPageDown);
        jToolBarSouth.add(bPageLast);
        pToolbarSouth.add(jToolBarSouth);
        pStatus.add(l);
        // 更新标签内容
        l.setText("当前选中的英雄是： " + htm.heros.get(t.getSelectedRow()).name);

        pSouth.add(pToolbarSouth,BorderLayout.NORTH);
        pSouth.add(pStatus,BorderLayout.SOUTH);

        //内容整合
        f.add(pToolbarNorth,BorderLayout.NORTH);
        f.add(sp, BorderLayout.CENTER);
        f.add(pSouth,BorderLayout.SOUTH);


//        增加按钮监听器
        bAdd.addActionListener(e -> {
            Hero hero = new Hero();
            generateDialog(f, "添加英雄", hero, dialog -> {
                //hero数据执行insert
                dao.add(hero);
                htm.heros=dao.list();
                JOptionPane.showMessageDialog(dialog, "新增成功！");
                dialog.dispose();
                refreshComboBox(cb);
                t.updateUI();
                // 选中 第一行 ，因为 DAO是按照 ID倒排序查询，所以第一行就是新加入的数据
                t.getSelectionModel().setSelectionInterval(0, 0);
            });
        });
        //删除按钮监听器
        bDelete.addActionListener(e -> {
            int option=JOptionPane.showConfirmDialog(f,"请确认是否删除:"+htm.heros.get(t.getSelectedRow()).name);
            if (JOptionPane.OK_OPTION == option) {
                int row = t.getSelectedRow();
                Hero h = htm.heros.get(row);
                //数据库中执行删除
                dao.delete(h.id);
                //用户选择的页码
                int page=cb.getSelectedIndex()+1;
//                如果用户当前选择的页码比最大的页码大，则按照最大的页码更新，else按用户使用的页码刷新
                refreshComboBox(cb);
                //如果当前用户选择的页码比删除后的最大页码大则当前页码的ID-1
                if(page>cb.getItemCount()){
                    //用dao做分页查询，查询结果给htm模型
                    htm.heros=dao.list(countIndex*(page-1),countIndex*cb.getItemCount());
                    cb.setSelectedIndex(page-2);
                }else{
                    htm.heros=dao.list(countIndex*(page-1),countIndex*page);
                    cb.setSelectedIndex(page-1);
                }
                JOptionPane.showMessageDialog(f, "删除成功！");
                t.updateUI();
                // 选中 第一行
                t.getSelectionModel().setSelectionInterval(0, 0);
            }

        });
//        编辑按钮监听器
        bModify.addActionListener(e -> {
            Hero hero = htm.heros.get(t.getSelectedRow());

            generateDialog(f, "编辑英雄", hero, dialog -> {
//                把hero传入做数据库update
                dao.update(hero);
                //用户选择的页码
                int page=cb.getSelectedIndex()+1;
                //用dao做分页查询，查询结果给htm模型
                htm.heros=dao.list(countIndex*(page-1),countIndex*page);
                JOptionPane.showMessageDialog(dialog, "编辑成功！");
                dialog.dispose();
                t.updateUI();
                t.getSelectionModel().setSelectionInterval(0, 0);
            });
        });
        // 使用selection监听器来监听table的哪个条目被选中
        t.getSelectionModel().addListSelectionListener(e -> {
            refreshLabel(t,l);
        });
        //对页码下拉做监听器
        cb.addActionListener(e -> {
            //用户选择的页码
            int page=cb.getSelectedIndex()+1;
            //用dao做分页查询，查询结果给htm模型
            htm.heros=dao.list(countIndex*(page-1),countIndex*page);
            t.updateUI();
            t.getSelectionModel().setSelectionInterval(0, 0);
            refreshLabel(t,l);
        });
        //对首页按钮做监听器
        bPageFirst.addActionListener(e -> {
            //得到首页的页码
            int page=cb.getItemCount();
            if(page>0){
                page=1;
                htm.heros=dao.list(countIndex*(page-1),countIndex*page);
                cb.setSelectedIndex(0);
                t.updateUI();
                t.getSelectionModel().setSelectionInterval(0, 0);
                refreshLabel(t,l);
            }
        });
        //对末页按钮做监听器
        bPageLast.addActionListener(e -> {
            //得到末页的页码
            int page=cb.getItemCount();
            if(page>0){
                htm.heros=dao.list(countIndex*(page-1),countIndex*page);
                cb.setSelectedIndex(page-1);
                t.updateUI();
                t.getSelectionModel().setSelectionInterval(0, 0);
                refreshLabel(t,l);
            }
        });
        //对下一页按钮做监听器
        bPageDown.addActionListener(e -> {
            //得到当前选择页的页码号
            int page=0;
            if (cb.getItemCount()!=0){
                page=cb.getSelectedIndex()+1;
                if(page<cb.getItemCount()){
                    page+=1;
                    htm.heros=dao.list(countIndex*(page-1),countIndex*page);
                    cb.setSelectedIndex(page-1);
                    t.updateUI();
                    t.getSelectionModel().setSelectionInterval(0, 0);
                    refreshLabel(t,l);
                }
            }

        });
        //对上一页按钮做监听器
        bPageUp.addActionListener(e -> {
            //得到当前选择页的页码号
            int page=0;
            if (cb.getItemCount()!=0){
                page=cb.getSelectedIndex()+1;
                if(page>1){
                    page-=1;
                    htm.heros=dao.list(countIndex*(page-1),countIndex*page);
                    cb.setSelectedIndex(page-1);
                    t.updateUI();
                    t.getSelectionModel().setSelectionInterval(0, 0);
                    refreshLabel(t,l);
                }
            }
        });

        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        f.setVisible(true);
    }
    // 增加/编辑 英雄界面
    private static void generateDialog(JFrame frame, String title, Hero hero, Consumer<JDialog> consumer) {
        // 对话框
        JDialog dialog = new JDialog(frame, title, true);
        dialog.setBounds(200, 400, 500, 200);
        dialog.setResizable(false);
        dialog.setLayout(new FlowLayout());

        // 组件
        JLabel lName=new JLabel("名称");
        JTextField tfName = new JTextField(hero.name);
        JLabel lHP=new JLabel("血量");
        JTextField tfHp = new JTextField(String.valueOf(hero.hp));
        JLabel lMaxHP=new JLabel("最大血量");
        JTextField tfMaxHp = new JTextField(String.valueOf(hero.maxHp));
        JLabel lSpeed=new JLabel("速度");
        JTextField tfSpeed = new JTextField(String.valueOf(hero.moveSpeed));
        tfName.setPreferredSize(new Dimension(80, 30));
        tfHp.setPreferredSize(new Dimension(80, 30));
        tfMaxHp.setPreferredSize(new Dimension(80, 30));
        tfSpeed.setPreferredSize(new Dimension(80, 30));

        dialog.add(lName);
        dialog.add(tfName);
        dialog.add(lHP);
        dialog.add(tfHp);
        dialog.add(lMaxHP);
        dialog.add(tfMaxHp);
        dialog.add(lSpeed);
        dialog.add(tfSpeed);

        // 提交按钮
        JButton button = (JButton) dialog.add(new JButton("提交"));
        // 提交按钮，响应事件
        button.addActionListener(e -> {
            String name = tfName.getText();
            // 通过name长度判断 名称是否为空
            if (name.length() == 0) {
                // 弹出对话框提示用户
                JOptionPane.showMessageDialog(dialog, "名称不能为空");

                // 名称输入框获取焦点
                tfName.grabFocus();
                return;
            }

            String hp = tfHp.getText().trim();
            try {
                // 把hp转换为浮点型，如果出现异常NumberFormatException表示不是浮点型格式
                Float.parseFloat(hp);
            } catch (NumberFormatException e1) {
                JOptionPane.showMessageDialog(dialog, "血量只能是小数 ");
                tfHp.grabFocus();
                return;
            }
            String maxhp = tfMaxHp.getText().trim();

            try {
                // 把hp转换为浮点型，如果出现异常NumberFormatException表示不是浮点型格式
                Float.parseFloat(maxhp);
            } catch (NumberFormatException e1) {
                JOptionPane.showMessageDialog(dialog, "最大血量只能是小数 ");
                tfMaxHp.grabFocus();
                return;
            }
            String speed = tfSpeed.getText().trim();

            try {

                Integer.parseInt(speed);
            } catch (NumberFormatException e1) {
                JOptionPane.showMessageDialog(dialog, "移动速度只能是整数");
                tfSpeed.grabFocus();
                return;
            }

            hero.setName(name);
            hero.setHp(Float.parseFloat(hp));
            hero.setMaxHp(Float.parseFloat(maxhp));
            hero.setMovespeed(Integer.parseInt(speed));

            // 行为注入
            consumer.accept(dialog);
        });
        dialog.setVisible(true);
    }
    public static void refreshComboBox(JComboBox cb){
        //获取数据条数
        iTotalHero=dao.getTotal();
        //生成分页计数器数组
        String num[];
        if(iTotalHero%10==0){
            num=new String[(int)(iTotalHero/10)];
        }else {
            num=new String[(int)(iTotalHero/10)+1];
        }
        for(int i=0;i<num.length;i++){
            int j=i+1;
            num[i]=String.valueOf(j);
        }
        //重新初始化combobox
        DefaultComboBoxModel model = new DefaultComboBoxModel(num);
        cb.setModel(model);


    }
    //重新根据选择的行刷新label
    public static void refreshLabel(JTable t,JLabel l){
        // 获取哪一行被选中了
        int row = t.getSelectedRow();
        // 根据选中的行，到HeroTableModel中获取对应的对象
        Hero h = htm.heros.get(row);
        // 更新标签内容
        l.setText("当前选中的英雄是： " + h.name);

    }

}
/*HeroTableModel1*/
package GUI.study;

import java.util.List;
import javax.swing.table.AbstractTableModel;

import JDBC.study.HeroDAO;
import charactor.Hero;

public class HeroTableModel1 extends AbstractTableModel {
    public  int pageSize;
    public  int curPage;
    public List<Hero> heros;

    public HeroTableModel1(int pageSize,int curPage){
        this.pageSize=pageSize;
        this.curPage=curPage;
        heros = new HeroDAO().list((this.curPage-1)*this.pageSize,this.pageSize);
    }
    public HeroTableModel1(){
        heros = new HeroDAO().list();
    }

    String[] columnNames = new String[] { "id", "name", "hp", "maxhp","speed" };


    // heros.size返回一共有多少行
    public int getRowCount() {
        // TODO Auto-generated method stub
        return heros.size();
    }

    public int getColumnCount() {
        // TODO Auto-generated method stub
        return columnNames.length;
    }

    public String getColumnName(int columnIndex) {
        // TODO Auto-generated method stub
        return columnNames[columnIndex];
    }

    public boolean isCellEditable(int rowIndex, int columnIndex) {
        return false;
    }

    // 先通过heros.get(rowIndex)获取行对应的Hero对象
    // 然后根据columnIndex返回对应的属性
    public Object getValueAt(int rowIndex, int columnIndex) {
        Hero h = heros.get(rowIndex);
        if (0 == columnIndex)
            return h.id;
        if (1 == columnIndex)
            return h.name;
        if (2 == columnIndex)
            return h.hp;
        if (3 == columnIndex)
            return h.maxHp;
        if (4 == columnIndex)
            return h.moveSpeed;
        return null;
    }

}

回答已经提交成功，正在审核。请于我的回答处查看回答记录，谢谢

2022-05-27 JAVA 中级-图形界面-表格综合练习 ——最后两个练习，下拉框反而是最好做的

M_GX

关于 JAVA 中级-图形界面-表格综合练习的提问

我是按照我思考的方式编写的代码，可能有些地方不符合部分人的阅读习惯

package GUILearn;

import JDBC.HeroDao;
import JDBC.Heros;
import jdk.nashorn.internal.scripts.JO;

import javax.swing.*;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.sql.SQLException;

//在table中仅仅显示10条数据。
//        在下方出现4个按钮
//        首页 上一页 下一页 末页
//借助下拉框实现下拉框分页
public class Day_202205232142 {
    private static int startIndex;
    private static HeroDao hd=new HeroDao();
    private static HeroTableModel heroTableModel=new HeroTableModel();

    public static void main(String[] args) {
        final int countIndex=10;
        String num[];
        if(hd.list().size()%10==0){
            num=new String[(int)(hd.list().size()/10)];
        }else {
            num=new String[(int)(hd.list().size()/10)+1];
        }
        for(int i=0;i<num.length;i++){
            int j=i+1;
            num[i]=String.valueOf(j);
        }

        JFrame f = new JFrame("LOL");
        f.setBounds(200,200,600,400);
        f.setLayout(null);
        f.setResizable(false);

        JTable t=getTable(0,10);
        JScrollPane sp = new JScrollPane(t);
        sp.setBounds(0,0,595,250);

        JButton bAdd=getButton("增加",240,20,80,30);
        JButton bDelete=getButton("删除",240,20,80,30);
        JButton bEdit=getButton("编辑",340,20,80,30);
        JButton bFirst=getButton("首页",85,70,80,30);
        bFirst.setEnabled(false);
        JButton bLeast=getButton("上一页",185,70,80,30);
        bLeast.setEnabled(false);
        JButton bNext=getButton("下一页",355,70,80,30);
        JButton bLast=getButton("末页",455,70,80,30);
        //下拉框
        JComboBox cb=getComboBox(num,285,70,50,30);
        cb.setSelectedIndex(0);//默认选0位

        


        JPanel p=getPanel();
        p.add(cb);
        cb.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                startIndex=cb.getSelectedIndex();
                System.out.println(startIndex);
                if(startIndex==0){
                    bFirst.setEnabled(false);
                    bLeast.setEnabled(false);
                    bLast.setEnabled(true);
                    bNext.setEnabled(true);
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                }else if(startIndex==(int)(hd.list().size()/10)){
                    bFirst.setEnabled(true);
                    bLeast.setEnabled(true);
                    bNext.setEnabled(false);
                    bLast.setEnabled(false);
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                }else {
                    bFirst.setEnabled(true);
                    bLeast.setEnabled(true);
                    bNext.setEnabled(true);
                    bLast.setEnabled(true);
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                }
            }
        });
        p.add(bAdd);
        t.getSelectionModel().addListSelectionListener(new ListSelectionListener() {
            @Override
            public void valueChanged(ListSelectionEvent e) {
                bAdd.setLocation(140,20);
                p.add(bDelete);
                p.add(bEdit);
                p.updateUI();
            }
        });
        bAdd.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                JDialog d=getDialog();
                d.setModal(true);
                d.setResizable(false);
                d.add(getLabel("名称",50,50,80,30));
                d.add(getLabel("血量",50,100,80,30));
                JTextField tfName=getTextField("",100,50,100,30);
                d.add(tfName);
                JTextField tfHp=getTextField("",100,100,100,30);
                d.add(tfHp);

                JButton bSubmit=getButton("提交",100,150,100,30);
                d.add(bSubmit);

                bSubmit.addActionListener(new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        String name=tfName.getText();
                        String hp=tfHp.getText();
                        Heros hero=new Heros();
                        if(name.length()!=0){
                            hero.name=name;
                        }else {
                            JOptionPane.showMessageDialog(d,"名称不能为空！");
                            tfName.grabFocus();
                            return;
                        }
                        try {
                            hero.hp=Float.valueOf(hp);
                        }catch (Exception ex){
                            JOptionPane.showMessageDialog(d,"血量必须为数字！");
                            tfHp.grabFocus();
                            return;
                        }
                        try {
                            hd.add(hero);
                            JOptionPane.showMessageDialog(d,"提交成功！");
                            heroTableModel.heros=hd.list(0,10);
                            t.getSelectionModel().setSelectionInterval(0,0);
                            sp.updateUI();
                        } catch (SQLException ex) {
                            throw new RuntimeException(ex);
                        }

                    }
                });
            }
        });
        bDelete.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {

                int option=JOptionPane.showConfirmDialog(f,"确认删除？");
                if(option==JOptionPane.OK_OPTION){
                    int row=t.getSelectedRow();//取得选定条目的行号
                    Heros hero=heroTableModel.heros.get(row);//这里必须用heroTM进行调用
                    hd.delete(hero.id);
                    JOptionPane.showMessageDialog(f,"数据删除成功！");
                    heroTableModel.heros=hd.list(0,10);
                    sp.updateUI();
                }

            }
        });
        bEdit.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                Heros hero=heroTableModel.heros.get(t.getSelectedRow());
                String name= hero.name;
                String hp=String.valueOf(hero.hp);
                JDialog d=getDialog();
                d.setResizable(false);
                d.setModal(true);
                d.add(getLabel("名称",50,50,80,30));
                d.add(getLabel("血量",50,100,80,30));
                JTextField tfName=getTextField(name,100,50,100,30);
                d.add(tfName);
                JTextField tfHp=getTextField(hp,100,100,100,30);
                d.add(tfHp);

                JButton b=getButton("提交",100,150,100,30);
                d.add(b);
                b.addActionListener(new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        String namex= tfName.getText();
                        String hpx=tfHp.getText();
                        if(namex.length()!=0){
                            hero.name=namex;
                        }else {
                            JOptionPane.showMessageDialog(d,"名称不能为空！");
                            tfName.grabFocus();
                            return;
                        }
                        try {
                            hero.hp=Float.valueOf(hpx);
                        }catch (Exception ex){
                            JOptionPane.showMessageDialog(d,"血量必须为数字！");
                            tfHp.grabFocus();
                            return;
                        }
                        hd.update(hero);
                        JOptionPane.showMessageDialog(d,"数据变更成功！");
                        heroTableModel.heros=hd.list(0,10);
                        sp.updateUI();
                    }
                });

            }
        });
        p.add(bFirst);
        bFirst.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                startIndex=0;
                bFirst.setEnabled(false);
                bLeast.setEnabled(false);
                bLast.setEnabled(true);
                bNext.setEnabled(true);
                heroTableModel.heros=hd.list(startIndex*10,countIndex);
                sp.updateUI();
            }
        });
        p.add(bLeast);
        bLeast.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                bLast.setEnabled(true);
                bNext.setEnabled(true);
                startIndex-=1;
                System.out.println(startIndex);
                if(startIndex!=0){
                    bFirst.setEnabled(true);
                    bLeast.setEnabled(true);
                    heroTableModel.heros=hd.list(startIndex*10,10);
                    sp.updateUI();
                }else {
                   bFirst.setEnabled(false);
                   bLeast.setEnabled(false);
                   heroTableModel.heros=hd.list(startIndex*10,10);
                   sp.updateUI();
                }
            }
        });
        p.add(bNext);
        bNext.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                bFirst.setEnabled(true);
                bLeast.setEnabled(true);
                startIndex+=1;
                System.out.println(startIndex);
                if(startIndex!=(int)(hd.list().size()/10)){
                    bLast.setEnabled(true);
                    bNext.setEnabled(true);
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                }else{
                    bLast.setEnabled(false);
                    bNext.setEnabled(false);
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                }
            }
        });
        p.add(bLast);
        bLast.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                bFirst.setEnabled(true);
                bLeast.setEnabled(true);
                bNext.setEnabled(false);
                bLast.setEnabled(false);
                if(hd.list().size()%10==0){
                    startIndex=(int)(hd.list().size()/10)-1;
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                    t.getSelectionModel().setSelectionInterval(0,0);
                    startIndex=(int)(hd.list().size()/10);
                }else {
                    startIndex=(int)(hd.list().size()/10);
                    heroTableModel.heros=hd.list(startIndex*10,countIndex);
                    sp.updateUI();
                    t.getSelectionModel().setSelectionInterval(0,0);
                }
            }
        });



        f.add(p);
        f.add(sp);
        f.setDefaultCloseOperation(3);
        f.setVisible(true);
    }
    private static JTable getTable(int startIndex,int countIndex){
        heroTableModel.heros=hd.list(startIndex,countIndex);
        JTable t = new JTable(heroTableModel);
        t.setRowHeight(22);
        return t;
    }
    private static JPanel getPanel(){
        JPanel p = new JPanel();
        p.setBounds(0,245,595,160);
        p.setLayout(null);
        p.setBackground(Color.GRAY);
        return p;
    }
    private static JButton getButton(String name,int x,int y,int width,int height){
        JButton b = new JButton(name);
        b.setBounds(x,y,width,height);
        return b;
    }
    private static JDialog getDialog(){
        JDialog d = new JDialog();
        d.setBounds(300,300,300,300);
        d.setLayout(null);
        d.setVisible(true);
        return d;
    }
    private static JLabel getLabel(String name,int x,int y,int width,int height){
        JLabel label = new JLabel(name);
        label.setBounds(x,y,width,height);
        return label;
    }
    private static JTextField getTextField(String name,int x,int y,int width,int height){
        JTextField tf = new JTextField(name);
        tf.setBounds(x,y,width,height);
        return tf;
    }
    private static JComboBox getComboBox(String[] numbers,int x,int y,int width,int height){
        JComboBox cb = new JComboBox(numbers);
        cb.setBounds(x,y,width,height);
        return cb;
    }

}

应该无异常。。。。吧，试了好几遍，笨办法

回答已经提交成功，正在审核。请于我的回答处查看回答记录，谢谢

2022-04-12 能否使用这个分页组件做个jtable分页的使用教程呢？

javahack

关于 JAVA 中级-图形界面-表格综合练习的提问

https://www.cnblogs.com/rainbow70626/p/12591932.html，这个分页组件是我在网上找了很久找到的Swing分页组件，感觉无论是功能还是样式都很不错，不过自己技术太菜了，没看明白怎么用，哭……希望站长大佬做个视频给大家分享一下。谢谢

1 个答案

M_GX
答案时间：2022-05-23

JAVA 中级-图形界面-表格综合练习 ——删除

代码超过 5行，点击查看

回答已经提交成功，正在审核。请于我的回答处查看回答记录，谢谢

2022-01-04 练习 - 表格综合练习组合版

起个名

关于 JAVA 中级-图形界面-表格综合练习的提问

在table中仅仅显示10条数据。在下方出现4个按钮首页上一页下一页末页最后一页最后一页需要注意，如果数据库中的总数能够整除10，那么最后一页就显示10个，否则就显示不到除以10的余数。比如一共是25个，那么最后一页就显示5个。按钮的状态要求：如果有下一页的数据，才能点击下一页，否则下一页按钮是不可用的。通过如下代码设置代码不可用 JButton.setEnable(false) 对首页，上一页和末页也是一样。下拉框练习

private static int start = 0;  // 开始的条目索引值
	private static int count = 10;  // 每页10条
	static int Cpnum;
	
	public static void main(String[] args) {
		
		JFrame f = new JFrame("League of Leagends");
		f.setSize(450, 350);
		f.setLocation(200, 200);
		f.setLayout(null);
		
		// 创建一个TableModel
		HeroTableModel htm = new HeroTableModel(start, count);
		
		// 根据 TableModel来创建 Table
		JTable t = new JTable(htm);				
		JScrollPane sp = new JScrollPane(t);
		sp.setBounds(0, 0, 450, 210);
		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
		t.getSelectionModel().setSelectionInterval(0, 0);
		int Items = new JTable(new HeroTableModel()).getRowCount(); // 每次取值时条目数都会更新
		
		JPanel p = new JPanel();
		p.setBounds(0, 220, 450, 40);
		JPanel pp = new JPanel();
		pp.setBounds(0, 260, 450, 40);
		JButton bAdd = new JButton("增加");
		JButton bDel = new JButton("删除");
		JButton bEdi = new JButton("编辑");
		JButton bHpa = new JButton("首页");
		JButton bPpa = new JButton("上一页");
		  // 下拉框分页
        String[] pages = getPages(Items);
        JComboBox cbp = new JComboBox(pages);
		JButton bNpa = new JButton("下一页");
		JButton bLpa = new JButton("末页");
		p.add(bAdd);
		p.add(bDel);
		p.add(bEdi);
		pp.add(bHpa);
		pp.add(bPpa);
		pp.add(cbp);
		pp.add(bNpa);
		pp.add(bLpa);
	
		
		JDialog d = new JDialog();
        d.setTitle("LOL");
        d.setSize(300, 250);
        d.setLocation(200, 200);
        d.setLayout(null);   
        // 编辑对话框
        JDialog d1 = new JDialog();
        d1.setSize(300, 250);
        d1.setLocation(200, 200);
        d1.setLayout(null);
		
		final JLabel lName = new JLabel("名称");
		final JTextField tlName = new JTextField("");
		final JLabel lHp = new JLabel("血量");
		final JTextField tlHp = new JTextField("");
		final JLabel lDamage = new JLabel("伤害");
		final JTextField tlDamage = new JTextField("");
		
		
		lName.setBounds(20, 20, 50, 30);
		tlName.setBounds(120, 20, 100, 30);
		lHp.setBounds(20, 60, 50, 30);
		tlHp.setBounds(120, 60, 100, 30);
		lDamage.setBounds(20, 100, 50, 30);
		tlDamage.setBounds(120, 100, 100, 30);
        JButton b = new JButton("提交");
        JButton b1 = new JButton("提交");
        b.setBounds(100, 150, 80, 30);
        b1.setBounds(100, 150, 80, 30);
        
        // 默认显示首页
       Visible(htm, t, Items); 
       
        f.add(sp);
		f.add(p);
		f.add(pp);
		
		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		f.setVisible(true);
			
		// 下拉框条目监听
		cbp.addItemListener(new ItemListener() {
			@Override
			public void itemStateChanged(ItemEvent e) {
				// 下拉框当前页展示
			   ComboxV(htm, t, cbp, Items);
			}			
		});
		
		// 给增加按钮添加监听
 		bAdd.addActionListener(new ActionListener() {
 			@Override
 			public void actionPerformed(ActionEvent e) {
				tlName.setText("");
				tlHp.setText("");
				tlDamage.setText("");
 				d.add(lName);
 				d.add(tlName);
 				d.add(lHp);
 				d.add(tlHp);
 				d.add(lDamage);
 				d.add(tlDamage);
 		        d.add(b);
 				d.setVisible(true);
 			}
        });
 	
	 	// 给编辑按钮添加监听
		bEdi.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				int row = t.getSelectedRow();
				Hero h = htm.heros.get(row);
				tlName.setText(h.name);
				tlHp.setText(String.valueOf(h.hp));
				tlDamage.setText(String.valueOf(h.damage));
	            d1.add(lName);
				d1.add(tlName);
				d1.add(lHp);
				d1.add(tlHp);
				d1.add(lDamage);
				d1.add(tlDamage);
				d1.add(b1);
				d1.setVisible(true);
            	
			}
	    });
     			
		// 给增加键的提交按钮添加监听
		b.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				if(tlDamage.getText().length() == 0 || tlHp.getText().length() == 0 || tlName.getText().length() == 0) {
					JOptionPane.showMessageDialog(f, "输入框内容为空！");
				}else if(tlDamage.getText().length() == 0) {
						JOptionPane.showMessageDialog(f, "输入框内容为空！");
						tlDamage.grabFocus();
						if(tlHp.getText().length() == 0) {
							JOptionPane.showMessageDialog(f, "输入框内容为空！");
							tlHp.grabFocus();
							if(tlName.getText().length() == 0) {
								JOptionPane.showMessageDialog(f, "输入框内容为空！");
								tlName.grabFocus();
							}
						}
					} 
				else {
					if (tlHp.getText().contains(".")) {
						char[] cs = tlHp.getText().toCharArray();
						int tt = 0;
						for (char c0 : cs) {
							if(c0 == '.')
								tt++;
						} 
						if (tt == 1 && cs[0] != '.') {
							boolean tf = true;
							while(tf) {
								for (char c1 : cs) {
									if (c1 != '0' && c1 != '1' && c1 != '2' && c1 != '3' && c1 != '4' && c1 != '5' && c1 != '6' && c1 != '7' && c1 != '8' && c1 != '9' && c1 != '.' ) {
										tf = false;
										JOptionPane.showMessageDialog(f, "血量只能是小数！");
										tlHp.grabFocus();
									    break;
									} 
								}
								if(tf == true) {
									break;
								}
							}
							if(tf) {
								HeroDAO dao = new HeroDAO();
								// 根据输入框数据创建一个Hero对象
								Hero h = new Hero();
								h.name =tlName.getText();
								h.hp = Float.parseFloat(tlHp.getText());
								h.damage = Integer.parseInt(tlDamage.getText());
										
								// 通过dao把对象加入数据库
								dao.add(h);
								// 通过dao更新tablemodel中的数据
								htm.heros = dao.list();
								// 调用JTable的updateUI，刷新界面。
								t.updateUI();
								JOptionPane.showMessageDialog(f, "提交成功!");
								// 新增数据之后；默认选择更新后的第一行
								t.getSelectionModel().setSelectionInterval(0, 0);
							}
						} else {
							JOptionPane.showMessageDialog(f, "血量只能是小数！");	
							tlHp.grabFocus();
						}
					} else {
						JOptionPane.showMessageDialog(f, "血量只能是小数！");	
						tlHp.grabFocus();
					}
				}			
			}		
		});
		
		// 给删除按钮添加监听
		bDel.addActionListener(new ActionListener() {
 			@Override
 			public void actionPerformed(ActionEvent e) {
 				HeroDAO dao = new HeroDAO();
 				// 删除选中行
 				if (false == t.isRowSelected(t.getSelectedRow()) )
 					 JOptionPane.showMessageDialog(f, "删除前应该选中一行!");
 				else {
	 				int option = JOptionPane.showConfirmDialog(f, "确认要删除？");
	 		        if (JOptionPane.OK_OPTION == option) {
	 		            String answer = JOptionPane.showInputDialog(f, "请输入yes，删除后后果自负");
	 		            int row = t.getSelectedRow();
	 		            Hero hero = htm.heros.get(row);
						dao.delete(hero);
						htm.heros = dao.list();
						// 通过dao更新tablemodel中的数据
						htm.heros = dao.list();
						// 调用JTable的updateUI，刷新界面。
						t.updateUI();
	 		            if ("yes".equals(answer))
	 		                JOptionPane.showMessageDialog(f, "删除成功！");
	 		        }
 				}
 			}
        });
		
		// 给编辑键的提交按钮添加监听
		b1.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				if (false == t.isRowSelected(t.getSelectedRow()) )
					 JOptionPane.showMessageDialog(f, "编辑前应该选中一行!");
				else {
 		            Hero hero = htm.heros.get(t.getSelectedRow());
					HeroDAO dao = new HeroDAO();
					if(tlDamage.getText().length() == 0 || tlHp.getText().length() == 0 || tlName.getText().length() == 0) {
						JOptionPane.showMessageDialog(f, "输入框内容为空！");
					}else if(tlDamage.getText().length() == 0) {
							JOptionPane.showMessageDialog(f, "输入框内容为空！");
							tlDamage.grabFocus();
							if(tlHp.getText().length() == 0) {
								JOptionPane.showMessageDialog(f, "输入框内容为空！");
								tlHp.grabFocus();
								if(tlName.getText().length() == 0) {
									JOptionPane.showMessageDialog(f, "输入框内容为空！");
									tlName.grabFocus();
								}
							}
					} else {
						if (tlHp.getText().contains(".")) {
							char[] cs = tlHp.getText().toCharArray();
							int tt = 0;
							for (char c0 : cs) {
								if(c0 == '.')
									tt++;
							} 
							if (tt == 1 && cs[0] != '.') {
								boolean tf = true;
								while(tf) {
									for (char c1 : cs) {
										if (c1 != '0' && c1 != '1' && c1 != '2' && c1 != '3' && c1 != '4' && c1 != '5' && c1 != '6' && c1 != '7' && c1 != '8' && c1 != '9' && c1 != '.' ) {
											tf = false;
											JOptionPane.showMessageDialog(f, "血量只能是小数！");
											tlHp.grabFocus();
										    break;
										} 
									}
									if(tf == true) {
										break;
									}
								}
								if(tf) {
									hero.name =tlName.getText();
									hero.hp = Float.parseFloat(tlHp.getText());
									hero.damage = Integer.parseInt(tlDamage.getText());		
									// 通过dao更新数据库
									dao.update(hero);
									htm.heros = dao.list();
									t.updateUI();
									JOptionPane.showMessageDialog(f, "提交成功!");
									// 更新数据之后；默认选择更新后的第一行
									t.getSelectionModel().setSelectionInterval(0, 0);
								}
							} else {
								JOptionPane.showMessageDialog(f, "血量只能是小数！");	
								tlHp.grabFocus();
							}
						} else {
							JOptionPane.showMessageDialog(f, "血量只能是小数！");	
							tlHp.grabFocus();
						}				
					}
				}						
			}		
		});
		
		// 给首页按钮添加监听
		bHpa.addActionListener(new ActionListener() {
 			@Override
 			public void actionPerformed(ActionEvent e) {
 				Cpnum  = pageNum(htm, t, Items);
 				if (Cpnum == 1) { //判断首页
 					bHpa.setEnabled(false);
 					bPpa.setEnabled(false);
 				} else {
	 				if (Items%count == 0)
	 					htm.heros = new HeroDAO().list(0, count);
	 				else {
	 					if (Items/count == 0)
	 						htm.heros = new HeroDAO().list(0, Items);
	 					else
	 						htm.heros = new HeroDAO().list(0, count);
	 				}	
	 				t.updateUI();
 				}
				if (bNpa.isEnabled() == false || bLpa.isEnabled() == false) {
					bNpa.setEnabled(true);
					bLpa.setEnabled(true);
				}		
 			}
        });
		
		// 给上一页按钮添加监听
		bPpa.addActionListener(new ActionListener() {
 			@Override
 			public void actionPerformed(ActionEvent e) {
 				Cpnum  = pageNum(htm, t, Items);
 				if (Cpnum == 1) {
 					bPpa.setEnabled(false);
					bHpa.setEnabled(false);
 				} else {
	 				start -= count;
	 				if (Items%count == 0)
	 					htm.heros = new HeroDAO().list(start, count);
	 				else {
	 					if (Items/count == 0) {
	 						bPpa.setEnabled(false);
	 						bHpa.setEnabled(false);
	 					}
	 					else
	 						htm.heros = new HeroDAO().list(start, count);
	 				}
 				}
				t.updateUI();
				if (bNpa.isEnabled() == false || bLpa.isEnabled() == false) {
 					bNpa.setEnabled(true);
 					bLpa.setEnabled(true);
 				}
 			}
        });
	
		// 给下一页按钮添加监听
		bNpa.addActionListener(new ActionListener() {
 			@Override
 			public void actionPerformed(ActionEvent e) {
 				Cpnum  = pageNum(htm, t, Items);
 				if (Items%count == 0) { //末页判断
					if (Cpnum == Items/count) {
	 					bNpa.setEnabled(false);
						bLpa.setEnabled(false);
	 				} else {
	 					if (Cpnum == 1)  // 首页判断
	 						start = 0;
	 					start += count;
	 	 				if (Items%count == 0)
	 	 					htm.heros = new HeroDAO().list(start, count);
	 	 				else {
	 	 					if (Items/count == 0)
	 	 						htm.heros = new HeroDAO().list(start, Items);
	 	 					else
	 	 						htm.heros = new HeroDAO().list(start, count);
	 	 				}	
	 				}
				} else { // 末页判断
					if (Cpnum == Items/count + 1) {
	 					bNpa.setEnabled(false);
						bLpa.setEnabled(false);
	 				} else {
	 					if (Cpnum == 1)  // 首页判断
	 						start = 0;
	 					start += count;
	 	 				if (Items%count == 0)
	 	 					htm.heros = new HeroDAO().list(start, count);
	 	 				else {
	 	 					if (Items/count == 0)
	 	 						bNpa.setEnabled(false);
	 	 					else
	 	 						htm.heros = new HeroDAO().list(start, count);
	 	 				}	
	 				}
				}			
				t.updateUI();
				if (bHpa.isEnabled() == false || bPpa.isEnabled() == false) {
					bHpa.setEnabled(true);
					bPpa.setEnabled(true);
				}			
 			}
        });	
		
		// 给末页按钮添加监听
		bLpa.addActionListener(new ActionListener() {
 			@Override
 			public void actionPerformed(ActionEvent e) {
 				Cpnum  = pageNum(htm, t, Items);
 				if (Items%count == 0) { //末页判断
	 				if (Cpnum == Items/count) {
	 					bNpa.setEnabled(false);
						bLpa.setEnabled(false);
	 				} 
 				} else { // 末页判断
					if (Cpnum == Items/count + 1) {
	 					bNpa.setEnabled(false);
						bLpa.setEnabled(false);
	 				}
 				}
 				if (Items%count == 0) {
 					start = (Items/count  - 1) * count;
 					htm.heros = new HeroDAO().list(Items - count, count);
 				}
 				else {
 					if (Items/count == 0) {
 						;  // 前面已经设置相关按键非赋能
 					}
 					else {
 						start = (Items/count) * count;
 						htm.heros = new HeroDAO().list(start, Items%count);
 					}
 				}
 				t.updateUI();
 				if (bHpa.isEnabled() == false || bPpa.isEnabled() == false) {
					bHpa.setEnabled(true);
					bPpa.setEnabled(true);
				}			
 			}
        });		
		
	}
	
	public static void ComboxV(HeroTableModel htm,  JTable t, JComboBox cbp, int Items) {
		if (Items % count == 0) {
			if (cbp.getSelectedItem().toString() == "1")
				htm.heros = new HeroDAO().list(0, count);
			else if (cbp.getSelectedItem().toString() == String.valueOf(Items / count)) 
				htm.heros = new HeroDAO().list((Items / count - 1) * count, count);
			else {
				int Cpag = Integer.parseInt(cbp.getSelectedItem().toString());
				htm.heros = new HeroDAO().list((Cpag-1) * count, count);
			}
		} else {
			if (Items / count == 0)
				htm.heros = new HeroDAO().list(0, Items);
			else if (cbp.getSelectedItem().toString() == String.valueOf(Items/count + 1)) 
				htm.heros = new HeroDAO().list((Items / count) * count, Items % count);
			else {
				int Cpag = Integer.parseInt(cbp.getSelectedItem().toString());
				htm.heros = new HeroDAO().list((Cpag-1) * count, count);
			}
		}
		t.updateUI();
	}

	// 默认显示首页
	public static void Visible(HeroTableModel htm, JTable t, int Items) {
		if (Items%count == 0)
			htm.heros = new HeroDAO().list(0, count);
		else {
			if (Items/count == 0)
				htm.heros = new HeroDAO().list(0, Items);
			else
				htm.heros = new HeroDAO().list(0, count);
		}	
		t.updateUI();
	}
		
	// 返回当前页数
	private static int pageNum(HeroTableModel htm, JTable t, int Items) {
		int Cpnum = 0;
		int row = t.getSelectedRow();
		List<Hero> heros1 = new HeroDAO().list(0, Short.MAX_VALUE);
		for (int i = 0; i < Items; i++) {
				if(htm.heros.get(row).id == heros1.get(i).id)
						Cpnum = i/10 + 1;
			}
		return Cpnum;
	}
	
	// 下拉框页数
	public static String[] getPages(int Items) {		
	    int pags;
	    if (Items % count == 0)
	    	pags = Items / count;
	    else
	    	pags = Items / count + 1;
	    String[] pages =  new String[pags];
	    for (int i = 0; i < pags; i++) {
	    	pages[i] =String.valueOf(i + 1);
	    }
		return pages;
	}

回答已经提交成功，正在审核。请于我的回答处查看回答记录，谢谢

2021-03-16 整个表格综合练习题目-打卡答案

991015

关于 JAVA 中级-图形界面-表格综合练习的提问

代码的各处解释，我觉得我写的很清楚了，希望能帮到未来看到这条提问的你

import javax.swing.JTextField;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent ;
import java.awt.event.ItemListener;

import java.util.ArrayList;
import java.util.List;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.ListSelectionModel;

import test_Item.Item; //这个换成你们自己的Hero
import 表格_9.Test_connectSql_ItemTableModel;	//换成你们自己的HeroTableModel
import 返回数据库链接.ItemDAO;	//换成你们自己的HeroDAO

public class Test_SqlToTable {
	static int pages = 0 ;	//总页数
	static int page = 0 ;	//当前页数
	static List<Item>[] PPP ; //集合框架List<Item>数组，PPP里有多少List<Item>就有多少页，每个List<Item>存储了10条数据
	public static void main(String[] args) {
		JFrame f = new JFrame("监听表格选中") ;
		f.setSize(400, 500);
		f.setLocation(200, 200);
		f.setLayout(null);
		
		//这个当成你们每个人的HeroTableModel()  ,因为我当初没写HeroTableModel()，我写的Item道具类
		final Test_connectSql_ItemTableModel htm = new Test_connectSql_ItemTableModel() ;
		final JTable t = new JTable(htm) ;
		t.setRowHeight(29);//设置行高
		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);//设置模式为只能选中一行
		
		//使用方法splitList(List<Item>) 返回一个List<Item>{]数组，每一个List里存储10条数据
		PPP = splitList(htm.mains) ; 
		htm.mains = PPP[page] ;//page目前为0，所以直接显示首页
		
		JScrollPane sp = new JScrollPane(t) ;//添加带滚动条的Panel，将表格到放到Panel里
		sp.setBounds(0, 0, 390, 320);//设置表格位置和显示大小
		
		//创建一个中部的JPanel，用于显示操作按钮
		JPanel p = new JPanel() ;
		p.setLayout(new FlowLayout());
		p.setBounds(0, 350, 390, 40);	//设置位置和大小
		final JButton insertButton = new JButton("增加") ;p.add(insertButton) ;
		final JButton deleteButton = new JButton("删除") ;p.add(deleteButton) ;
		final JButton setButton    = new JButton("编辑") ;p.add(setButton) ;

		//创建一个底部的JPanel,用于显示窗口的上下翻页按钮
		JPanel p2 = new JPanel() ;
		p.setLayout(new FlowLayout());
		p2.setBounds(0, 400, 390, 40);	//设置位置和大小
		final JButton HPage 		= new JButton("首页") ;		p2.add(HPage) ;
		final JButton PreviousPage 	= new JButton("上一页") ;	p2.add(PreviousPage) ;
		//中间的按键
		String pagel[] = new String[pages] ;
		for(int i=0;i<pages;i++){
			pagel[i] = String.valueOf(i) ;
		}
		final JComboBox<String> optionPage = new JComboBox<>(pagel);		p2.add(optionPage) ;//下拉框
		optionPage.setSelectedItem("0");//默认显示第一页
		final JButton NextPage 		= new JButton("下一页") ;	p2.add(NextPage) ;
		final JButton LastPage 		= new JButton("末页") ;		p2.add(LastPage) ;
		
		Thread T1 = new Thread(){//创建一个匿名线程，
			public void run(){
				while(true){
					try{
						Thread.sleep(80); //每隔80ms判断一次
						if(page==0){	//如果页码为0 ，首页和上一页  不可按
							HPage.setEnabled(false);
							PreviousPage.setEnabled(false);
							NextPage.setEnabled(true);
							LastPage.setEnabled(true);
						}else if(page==pages-1){	//如果页码为最后一页，末页和下一页  不可按
							HPage.setEnabled(true);
							PreviousPage.setEnabled(true);
							NextPage.setEnabled(false);
							LastPage.setEnabled(false);
						}else{				//其它时候，都可按
							HPage.setEnabled(true);
							PreviousPage.setEnabled(true);
							NextPage.setEnabled(true);
							LastPage.setEnabled(true);
						}
					}catch(InterruptedException e){
						e.printStackTrace();
					}
				}
			}
		};T1.start();  
 //本来是没打算多写一个线程，但是那个按钮可按和不可按
//在“首页、上一页、下一页、末页”这几个按钮的的事件监听下都要单独设置，所以想到多一个线程来判定
		
		f.add(p2) ;
		f.add(p) ;
		f.add(sp) ;
//*******************************上为窗口UI，下为按键监听*************************************
		
		//添加"增加"按钮监听
		insertButton.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				insertWindow(f) ;   //打开添加数据窗口
				PPP = splitList((new ItemDAO()).list()) ;//刷新表格数据 
				htm.mains =PPP[0] ;  
				optionPage.setSelectedItem(String.valueOf(page)) ;
				t.updateUI();	//刷新表格
			}
		});
		//添加"删除"按钮监听
		deleteButton.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				if(t.getSelectedRow()==-1){
					JOptionPane.showMessageDialog(f, "删除前应该选中一行数据");
				}else{
					int option = JOptionPane.showConfirmDialog(f, "确认要删除？");
					if(option == JOptionPane.OK_OPTION){
						int row = t.getSelectedRow();  //获取选中的数据在table里的数组下标
						Item item = htm.mains.get(row) ; //通过上一行代码获取到的数组下标获取选中的那一行的全部数据
						ItemDAO ItemSql = new ItemDAO() ;  //ItemDAO是个数据库连接，并且有多个数据库方法
						ItemSql.delete(item.id);
						PPP = splitList((new ItemDAO()).list()) ; //刷新表格数据 
						htm.mains =PPP[0] ;  
						optionPage.setSelectedItem(String.valueOf(page)) ;//更新下拉框的页码
						t.updateUI();		//刷新表格
					}
				}
			}
		});
		//添加"编辑"按钮监听
		setButton.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				if(t.getSelectedRow()==-1){
					JOptionPane.showMessageDialog(f, "编辑前应该选中一行数据");
				}else{
					int row = t.getSelectedRow();
					Item item = htm.mains.get(row) ;
					System.out.println(item.name+"-"+item.price);
					updateWindow(f,item) ;		 //打开更新数据窗口
					PPP = splitList((new ItemDAO()).list()) ; 
					htm.mains =PPP[0] ; 
					optionPage.setSelectedItem(String.valueOf(page)) ;//更新下拉框的页码
					t.updateUI();
				}
			}
		});
		//添加"首页"按键监听
		HPage.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				PPP = splitList((new ItemDAO()).list()) ; //刷新表格数据    首页按钮带刷新表格的功能
				htm.mains =PPP[0] ; 
				page = 0 ;
				optionPage.setSelectedItem(String.valueOf(page)) ;//更新下拉框的页码
				t.updateUI() ;
			}
		});
		//添加"上一页"按键监听
		PreviousPage.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				htm.mains =PPP[page-1] ; 
				page-=1 ;
				optionPage.setSelectedItem(String.valueOf(page)) ;//更新下拉框的页码
				t.updateUI() ;
			}
		}); 
		
		//添加"下拉框"监听
		optionPage.addItemListener(new ItemListener(){
			public void itemStateChanged(ItemEvent evt){
				int pj = Integer.parseInt((String)evt.getItem()) ; //获取到的下拉框事件监听，先从Object转换成String，再转换成int
				page = pj ;		//更新页码
				htm.mains = PPP[pj] ;//刷新表格
				t.updateUI() ;
			}
		});
		
		
		//添加"下一页"按键监听
		NextPage.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				htm.mains =PPP[page+1] ;
				page++ ;
				optionPage.setSelectedItem(String.valueOf(page)) ;//更新下拉框的页码
				t.updateUI() ;
			}
		});
		//添加"末页"按键监听
		LastPage.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				htm.mains =PPP[pages-1] ;
				page=pages-1 ;
				optionPage.setSelectedItem(String.valueOf(page)) ;//更新下拉框的页码
				t.updateUI() ;
			}
		});
		
		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		f.setVisible(true);
	}
	
//****************************下为衍生窗口*************************************************
	
	//添加数据窗口
	public static void insertWindow(JFrame f){
		JDialog d = new JDialog(f) ;
		d.setModal(true);
		d.setTitle("增加一条数据");
		d.setSize(300,200);
		d.setLocation(50+f.getX(),100+f.getY()) ;
		d.setLayout(null);
		JLabel itemname = new JLabel("名称：") ;		itemname.setBounds(50,20,40,20);
		JLabel itemprice = new JLabel("价格：") ;	itemprice.setBounds(50,71,40,20);
		JTextField textname = new JTextField("");	textname.setBounds(150,16,80,30);
		JTextField textprice = new JTextField("") ;	textprice.setBounds(150,66,80,30);
		JButton submit = new JButton("提交") ; 		submit.setBounds(100,110,80,30);
			
		submit.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				String Name = textname.getText() ;
				String Price = textprice.getText() ;
				System.out.println(Price);
				if(check(d,Name,Price)){
					ItemDAO dao = new ItemDAO();
					Item item = new Item() ;
					item.name = Name ;
					int itemPrice = Integer.valueOf(Price) ;
					item.price = itemPrice ;
					dao.add(item);
					JOptionPane.showMessageDialog(d, "添加成功");
					d.dispose();
				}
			}
		});
		
		d.add(itemname) ;
		d.add(itemprice) ;
		d.add(textname) ;
		d.add(textprice) ;
		d.add(submit) ;
		
		d.setVisible(true) ;
	} 
		
	//编辑数据窗口
	public static void updateWindow(JFrame f,Item item){
		JDialog d = new JDialog(f) ;
		d.setModal(true);
		d.setTitle("更新数据");
		d.setSize(300,200);
		d.setLocation(50+f.getX(),100+f.getY()) ;
		d.setLayout(null);
		
		JLabel itemname = new JLabel("名称：") ;		itemname.setBounds(50,20,40,20);
		JLabel itemprice = new JLabel("价格：") ;	itemprice.setBounds(50,71,40,20);
		JTextField textname = new JTextField(item.name);	textname.setBounds(150,16,80,30);
		JTextField textprice = new JTextField(String.valueOf(item.price)) ;	textprice.setBounds(150,66,80,30);
		JButton submit = new JButton("提交") ; 		submit.setBounds(100,110,80,30);
		
		submit.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e){
				String Name = textname.getText() ;
				String Price = textprice.getText() ;
				System.out.println(Price);
				if(check(d,Name,Price)){
					ItemDAO dao = new ItemDAO();
					item.name = Name ;
					int itemPrice = Integer.valueOf(Price) ;
					item.price = itemPrice ;
					dao.update(item);
					JOptionPane.showMessageDialog(d, "更新数据成功");
					d.dispose();
				}
			}
		});
		
		d.add(itemname) ;
		d.add(itemprice) ;
		d.add(textname) ;
		d.add(textprice) ;
		d.add(submit) ;
		
		d.setVisible(true) ;
	} 
		
//************************************下为方法**************************************
	//输入项验证      名称不可为空       价格必须为整数
	public static boolean check(JDialog f,String t1,String t2){
		boolean test = false ;
		
		boolean o1 = true ;
		if(t1.length()==0){
			JOptionPane.showMessageDialog(f, "工具名称不可为空！");
			o1 = false ;
		}
			
		boolean o2 = true ;
		char price[] = t2.toCharArray();
		for(int i=0;i<price.length;i++){
			if(!Character.isDigit(price[i])){
				JOptionPane.showMessageDialog(f, "价格只能是整数！");
				o2 = false ;
				break ;
			}
		}
		if(o1==true&&o2==true){//当两项验证都为真时，才返回真
			test = true ;
		}
		return test ;
	}
	
	//分割传入的List
	public static List<Item>[] splitList(List<Item> list){	
		pages = list.size() / 10 ;
		int lastCount = list.size() % 10 ;	//取余数，如果最后一页不满10行，将最后的一页的行数赋值给lastCount
		if(lastCount != 0){pages+=1 ;}   //判断  如果最后一页的行数不为0，那总页数+1 
		@SuppressWarnings("unchecked")// 应该是解除下一行ArrayList警告的意思 这行有没有都可以
		List<Item>[] listItem = new ArrayList[pages]; 	//根据页数创建List<Item>[]数组
		for(int t=0;t<pages;t++){	//添加List<>集合框架到List<Item>数组里，数组里的每个List<Item>存储10行数据
			List<Item> SplitPage = new ArrayList<>() ;
			listItem[t] = SplitPage ;
		}
		int io = 0 ;
		int count = 0 ;//计数，每10个循环一次
		for(int i=0;i<list.size();i++){
			if(count==10){io++ ;count=0;}	//count每到10就重新变为0，然后io加1
			listItem[io].add(list.get(i)) ;
			count++ ;
		}
		return listItem ;
	}
}

4 个答案

qiemanqieman
答案时间：2022-08-06

本节所有问题的综合答案

代码超过 5行，点击查看

package gui;

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

import jdbc.HeroDAO;
import charactor.Hero;

public class UpdateTableToDB1 {
    private static int pageNum = 1;
    private static final int pageSize = 10; // number of records per page
    public static JFrame f = new JFrame("LoL");
    static final HeroTableModel htm = new HeroTableModel();
    static final JTable t = new JTable(htm);
    static JScrollPane sp = new JScrollPane(t);

    // 增加 一个 panel用于放置名称，血量输入框和增加 按钮
    static JPanel p = new JPanel();
    static JButton bAdd = new JButton("增加");
    static JButton bDel = new JButton("删除");
    static JButton bMod = new JButton("修改");

    // another panel used to change page
    static JPanel pPage = new JPanel();
    static JButton bFirstPage = new JButton("首页");
    static JButton bPrePage = new JButton("上一页");
    static JComboBox<Integer> cbPageChooser = new JComboBox<>();
    static JButton bNextPage = new JButton("下一页");
    static JButton bFinalPage = new JButton("末页");

    public static void main(String[] args) {

        init();
        initButtonAdd();
        initButtonDel();
        initButtonMod();
        initPageAction();

        f.setVisible(true);
    }

    private static void init() {

        f.setSize(600, 500);
        f.setLocationRelativeTo(null);
        f.setLayout(new BorderLayout());

        htm.pageNum = pageNum;
        htm.pageSize = pageSize;

        // 设置选择模式为 只能选中一行
        t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
        // 选中第一行 （基本0）
        t.getSelectionModel().setSelectionInterval(0, 0);
        t.setFont(new Font(null, Font.BOLD, 14));

        p.add(bAdd);
        p.add(bDel);
        p.add(bMod);

        int totalPageNum = (htm.heros.size() + pageSize - 1) / pageSize;
        for (int i = 1; i <= totalPageNum; ++i)
            cbPageChooser.addItem(Integer.valueOf(i));
        updatePageButtonStatus();
        pPage.add(bFirstPage);
        pPage.add(bPrePage);
        pPage.add(cbPageChooser);
        pPage.add(bNextPage);
        pPage.add(bFinalPage);

        f.add(p, BorderLayout.NORTH);
        f.add(sp, BorderLayout.CENTER);
        f.add(pPage, BorderLayout.SOUTH);
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    // 实现按钮翻页
    private static void initPageAction() {
        bFirstPage.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                pageNum = 1;
                updatePageButtonStatus();
            }
        });

        bPrePage.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (pageNum > 1)
                    pageNum -= 1;
                updatePageButtonStatus();
            }
        });

        bNextPage.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (pageNum < (htm.heros.size() + pageSize - 1) / pageSize)
                    pageNum += 1;
                updatePageButtonStatus();
            }
        });

        bFinalPage.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                pageNum = (htm.heros.size() + pageSize - 1) / pageSize;
                updatePageButtonStatus();
            }
        });

        cbPageChooser.addActionListener( new ActionListener(){
            public void actionPerformed(ActionEvent e){
                pageNum = Integer.parseInt(cbPageChooser.getSelectedItem().toString());
                updatePageButtonStatus();
            }
        });
    }

    // 点击翻页按钮后,更新按钮状态
    private static void updatePageButtonStatus() {
        htm.pageNum = pageNum;

        if (pageNum == 1) {
            bFirstPage.setEnabled(false);
            bPrePage.setEnabled(false);
        } else {
            bFirstPage.setEnabled(true);
            bPrePage.setEnabled(true);
        }
        if (pageNum == (htm.heros.size() + pageSize - 1) / pageSize) {
            bNextPage.setEnabled(false);
            bFinalPage.setEnabled(false);
        } else {
            bNextPage.setEnabled(true);
            bFinalPage.setEnabled(true);
        }
        cbPageChooser.setSelectedIndex(pageNum-1);
        t.updateUI();
    }

    // 为按钮添加监听
    private static void initButtonMod() {
        bMod.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                HeroDAO dao = new HeroDAO();

                if (t.getSelectedRow() == -1) {
                    JOptionPane.showMessageDialog(f, "Must select one line before delete");
                    return;
                }

                Hero hero = new Hero(); // hero needs to be modified
                int row = t.getSelectedRow();
                hero.id = Integer.parseInt(t.getValueAt(row, 0).toString());
                hero.name = t.getValueAt(row, 1).toString();
                hero.hp = Float.parseFloat(t.getValueAt(row, 2).toString());
                hero.damage = Integer.parseInt(t.getValueAt(row, 3).toString());

                // new dialog for editing
                JDialog dg = new JDialog();
                dg.setLocationRelativeTo(f);
                dg.setSize(200, 230);

                JPanel p = new JPanel();

                final JLabel lName = new JLabel("名称:");
                final JTextField tfName = new JTextField(hero.name);
                final JLabel lHp = new JLabel("血量:");
                final JTextField tfHp = new JTextField(Float.toString(hero.hp));
                final JLabel lDamage = new JLabel("伤害");
                final JTextField tfDamage = new JTextField(Integer.toString(hero.damage));
                JButton bCommit = new JButton("确定?");

                tfName.setPreferredSize(new Dimension(80, 30));
                tfHp.setPreferredSize(new Dimension(80, 30));
                tfDamage.setPreferredSize(new Dimension(80, 30));
                lHp.setPreferredSize(new Dimension(80, 30));
                lName.setPreferredSize(new Dimension(80, 30));
                lDamage.setPreferredSize(new Dimension(80, 30));

                p.add(lName);
                p.add(tfName);
                p.add(lHp);
                p.add(tfHp);
                p.add(lDamage);
                p.add(tfDamage);
                p.add(bCommit);
                dg.setContentPane(p);
                dg.setVisible(true);

                // 根据输入框数据创建一个Hero对象
                bCommit.addActionListener(new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        hero.name = tfName.getText().trim();
                        if (hero.name.length() == 0) {
                            JOptionPane.showMessageDialog(f, "名称不能为空");
                            tfName.grabFocus();
                            return;
                        }

                        try {
                            hero.damage = Integer.parseInt(tfDamage.getText());
                            hero.hp = Float.parseFloat(tfHp.getText());
                        } catch (NumberFormatException er) {
                            JOptionPane.showMessageDialog(f, "血量、伤害数据格式错误");
                            tfHp.grabFocus();
                            return;
                        }

                        // 通过dao把该对象加入到数据库
                        dao.update(hero);

                        // 通过dao更新tablemodel中的数据
                        htm.heros = dao.list();
                        // 调用JTable的updateUI，刷新界面。
                        // 刷新界面的时候，会到tablemodel中去取最新的数据
                        // 就能看到新加进去的数据了

                        t.updateUI();

                        // 选中 第一行
                        t.getSelectionModel().setSelectionInterval(0, 0);
                    }
                });
            }
        });
    }

    private static void initButtonDel() {
        bDel.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                HeroDAO dao = new HeroDAO();

                if (t.getSelectedRow() == -1) {
                    JOptionPane.showMessageDialog(f, "Must select one line before delete");
                    return;
                }
                int answer = JOptionPane.showConfirmDialog(f, "Sure to delete?", "Choose one option",
                        JOptionPane.YES_NO_CANCEL_OPTION);
                if (answer == JOptionPane.YES_OPTION) {
                    int row = t.getSelectedRow();
                    int id = Integer.parseInt(t.getValueAt(row, 0).toString());
                    dao.delete(id);

                    // 通过dao更新tablemodel中的数据
                    htm.heros = dao.list();
                    // 调用JTable的updateUI，刷新界面。
                    // 刷新界面的时候，会到tablemodel中去取最新的数据
                    // 就能看到新加进去的数据了
                    t.updateUI();
                    // 选中 第一行
                    t.getSelectionModel().setSelectionInterval(0, 0);

                    return;
                } else {
                    return;
                }
            }
        });
    }

    private static void initButtonAdd() {
        bAdd.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {

                HeroDAO dao = new HeroDAO();

                JDialog dg = new JDialog();
                dg.setLocationRelativeTo(f);
                dg.setSize(200, 200);

                JPanel p = new JPanel();

                final JLabel lName = new JLabel("名称:");
                final JTextField tfName = new JTextField("");
                final JLabel lHp = new JLabel("血量:");
                final JTextField tfHp = new JTextField("");
                JButton bCommit = new JButton("确定?");

                tfName.setPreferredSize(new Dimension(80, 30));
                tfHp.setPreferredSize(new Dimension(80, 30));
                lHp.setPreferredSize(new Dimension(80, 30));
                lName.setPreferredSize(new Dimension(80, 30));

                p.add(lName);
                p.add(tfName);
                p.add(lHp);
                p.add(tfHp);
                p.add(bCommit);
                dg.setContentPane(p);
                dg.setVisible(true);

                // 根据输入框数据创建一个Hero对象
                bCommit.addActionListener(new ActionListener() {
                    public void actionPerformed(ActionEvent e) {
                        Hero h = new Hero();
                        h.name = tfName.getText().trim();
                        if (h.name.length() == 0) {
                            JOptionPane.showMessageDialog(f, "名称不能为空");
                            tfName.grabFocus();
                            t.updateUI();
                            return;
                        }

                        // h.hp = Integer.parseInt(tfHp.getText());
                        try {
                            h.hp = Float.parseFloat(tfHp.getText());
                        } catch (NumberFormatException er) {
                            JOptionPane.showMessageDialog(f, "血量只能是小数");
                            tfHp.grabFocus();
                            t.updateUI();
                            return;
                        }

                        // 通过dao把该对象加入到数据库
                        dao.add(h);

                        // 通过dao更新tablemodel中的数据
                        htm.heros = dao.list();
                        // 调用JTable的updateUI，刷新界面。
                        // 刷新界面的时候，会到tablemodel中去取最新的数据
                        // 就能看到新加进去的数据了

                        t.updateUI();

                        // 选中 第一行 ，因为 DAO是按照 ID倒排序查询，所以第一行就是新加入的数据
                        t.getSelectionModel().setSelectionInterval(0, 0);
                    }
                });

            }
        });
    }

}

疾風亦有歸途
答案时间：2021-08-16

JComboBox的值是有可能會變得如果增加超過預設值那麼下拉框的值有可能長度不夠所以也需要更新

代码超过 5行，点击查看

/*
增加按钮:出现一个JDialog，在JDialog中进行增加
删除按钮:点击删除按钮之后，删除选中的行，并且刷新table中的数据，然后再默认选中第一行。
编辑按钮:点击的时候，弹出一个JDialog，显示选中的数据，并且能够修改。
      首选判断数据是否正确，是否为空，是否为数字等。 
      通过校验后，把数据保存到数据库，然后刷新table中的数据，并且选中第一条。

分页按钮:
在table中仅仅显示10条数据。在下方出现4个按钮
首页 上一页 下一页 末页
末页如果数据库中的总数能够整除10，那么最后一页就显示10个，否则就显示不到除以10的余数。 比如一共是25个，那么最后一页就显示5个。
如果有下一页的数据，才能点击下一页，否则下一页按钮是不可用的。通过如下代码设置代码不可用:
JButton.setEnable(false)
对首页，上一页和末页也是一样。

借助下拉框实现下拉框分页
*/

package swingtable02;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

public class Test01 {

	// 把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
	static HeroTableModel htm = new HeroTableModel();
	static JTable t = new JTable(htm);
	static JComboBox<String> cb;
	static JButton bHome = new JButton("首頁");
	static JButton bPre = new JButton("上一頁");
	static JButton bNext = new JButton("下一頁");
	static JButton bEnd = new JButton("尾頁");
	static int number = 10;// 每页显示10个
	static int start = 0;// 开始的页码

	public static void main(String[] args) {

		final JFrame f = new JFrame();
		f.setSize(400, 330);
		f.setLocation(200, 200);
		f.setLayout(new BorderLayout());
		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
		t.getSelectionModel().setSelectionInterval(0, 0);
		JScrollPane sp = new JScrollPane(t);// 帶滾動條

		JPanel pOperation = new JPanel();
		JButton bAdd = new JButton("增加");
		JButton bDel = new JButton("刪除");
		JButton bEdt = new JButton("修改");
		pOperation.add(bAdd);
		pOperation.add(bDel);
		pOperation.add(bEdt);

		// 下拉框頁數
		JPanel Pagination = new JPanel();
		String[] comboBoxItems = new String[new HeroDAO().getTotal()/number+1];
		for (int i = 0; i < comboBoxItems.length; i++) {
			comboBoxItems[i] = Integer.toString(i);
		}
		cb = new JComboBox<>(comboBoxItems);

		Pagination.add(bHome);
		Pagination.add(bPre);
		Pagination.add(cb);
		Pagination.add(bNext);
		Pagination.add(bEnd);

		f.setLayout(null);
		sp.setBounds(0, 0, 394, 200);
		pOperation.setBounds(0, 200, 394, 50);
		Pagination.setBounds(0, 250, 394, 200);
		f.add(sp);
		f.add(pOperation);
		f.add(Pagination);
		updateButtonStatus();
		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		f.setVisible(true);

		// 增加按鈕監聽器
		bAdd.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				new AddDialog(f).setVisible(true);// 放到函數中再設置
			}
		});

		// 刪除按鈕監聽器
		bDel.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				new DelDialog(f).setVisible(true);
			}
		});

		// 編輯按鈕監聽器
		bEdt.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				new EdtDialog(f).setVisible(true);
			}
		});

		// 首頁按鈕監聽器
		bHome.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start = 0;
				updateTable();
				updateButtonStatus();
			}
		});

		// 上一頁按鈕監聽器
		bPre.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start -= number;
				updateTable();
				updateButtonStatus();
			}
		});

		// 下一頁按鈕監聽器
		bNext.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start += number;
				updateTable();
				updateButtonStatus();
			}
		});

		// 尾頁按鈕監聽器
		bEnd.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start = last();
				updateTable();
				updateButtonStatus();
			}
		});

		// 下拉框監聽器
		cb.addItemListener(new ItemListener() {
			@Override
			public void itemStateChanged(ItemEvent evt) {
				if (evt.getSource() == cb) {
					if (evt.getStateChange() == ItemEvent.SELECTED) {
						int s = Integer.parseInt((String) cb.getSelectedItem());
						start = s * number;
						updateTable();
						updateButtonStatus();
					}
				}
			}
		});
	}

	private static void updateButtonStatus() {
		int last = last();
		// 是否有上一页
		if (0 != start) {
			bHome.setEnabled(true);
			bPre.setEnabled(true);
		}

		// 是否是第一页
		if (0 == start) {
			bHome.setEnabled(false);
			bPre.setEnabled(false);
		}

		// 是否是最后一页
		if (start == last) {
			bEnd.setEnabled(false);
			bNext.setEnabled(false);
		}
		// 是否有下一页
		if (start != last) {
			bEnd.setEnabled(true);
			bNext.setEnabled(true);
		}
		
	  cb.setSelectedIndex(start/number);//按照序號設置JComboBox裡面的選項
	  
	}

	private static int last() {
		// 最后一页开始的位置
		int last;
		int total = new HeroDAO().getTotal();
		// 最后一页要看总數是否能够整除每页显示的数量number
		if (0 == total % number) {
			// 假设总数是20，那么最后一页开始的位置就是10
			last = total - number;
		} else {
			// 假设总数是21，那么最后一页开始的位置就是20
			last = total - total % number;
		}
		return last;
	}

	// 增加
	@SuppressWarnings("serial")
	static class AddDialog extends JDialog {
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");
		JTextField tfName = new JTextField();
		JTextField tfHp = new JTextField();
		JButton bSubmit = new JButton("提交");

		AddDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);
			pSubmit.add(bSubmit);
			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());
							Hero h = new Hero();
							h.name = name;
							h.hp = hp;
							new HeroDAO().add(h);
							JOptionPane.showMessageDialog(f, "提交成功");
							AddDialog.this.setVisible(false);
							updateJbList();
							updateTable();
							updateButtonStatus();
						}
					}

				}
			});

		}
	}

	// 刪除
	@SuppressWarnings("serial")
	static class DelDialog extends JDialog {
		JLabel sure = new JLabel("確定要刪除嗎");

		JButton byes = new JButton("是");
		JButton bno = new JButton("否");
		JButton bback = new JButton("取消");

		DelDialog(JFrame f) {
			super(f);
			this.setModal(true);
			this.setLayout(null);

			JPanel pSubmit = new JPanel();
			JPanel bSubmit = new JPanel();

			pSubmit.add(byes);
			pSubmit.add(bno);
			pSubmit.add(bback);
			bSubmit.add(sure);

			pSubmit.setBounds(0, 40, 300, 150);
			bSubmit.setBounds(0, 20, 300, 150);
			this.add(pSubmit);
			this.add(bSubmit);
			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			
			byes.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					int row = t.getSelectedRow();
					// 根据选中的行，到HeroTableModel中获取对应的对象
					int id = htm.heros.get(row).getId();
					HeroDAO dao = new HeroDAO();
					dao.delete(id);
					DelDialog.this.setVisible(false);
					if(start==new HeroDAO().getTotal()) {
					start=start-number;
					}
					updateTable();
					updateButtonStatus();
				
				}
			});
			
			bno.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					DelDialog.this.setVisible(false);
				}
			});

			bback.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					DelDialog.this.setVisible(false);
					updateTable();
				}
			});

		}
	}

	// 修改
	@SuppressWarnings("serial")
	static class EdtDialog extends JDialog {
		int row = t.getSelectedRow();
		// 根据选中的行，到HeroTableModel中获取对应的对象
		Hero h = htm.heros.get(row);
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");

		JTextField tfName = new JTextField(h.name);
		JTextField tfHp = new JTextField(Float.toString(h.hp));

		JButton bSubmit = new JButton("提交");

		EdtDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);
			pSubmit.add(bSubmit);

			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener() {

				@Override
				public void actionPerformed(ActionEvent e) {
					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());
							new HeroDAO().add(h);
							JOptionPane.showMessageDialog(f, "提交成功");
							EdtDialog.this.setVisible(false);
							updateTable();
							updateButtonStatus();
						}
					}
				}
			});
		}
	}
	public static void updateJbList() {
	String[] comboBoxItems = new String[new HeroDAO().getTotal()/number+1];
	for (int i = 0; i < comboBoxItems.length; i++) {
		comboBoxItems[i] = Integer.toString(i);
		cb = new JComboBox<>(comboBoxItems);
	 }
	}
	
	public static void updateTable() {
		htm.heros = new HeroDAO().list(start, number);
		t.updateUI();
		if (!htm.heros.isEmpty())
			t.getSelectionModel().setSelectionInterval(0, 0);
	}

	private static boolean checkEmpty(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + "不能为空");
			tf.grabFocus();
			return false;
		}
		return true;
	}

	private static boolean checkNumber(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + "不能为空");
			tf.grabFocus();
			return false;
		}
		try {
			Integer.parseInt(value);
		} catch (NumberFormatException e) {
			JOptionPane.showMessageDialog(null, msg + "只能是整数");
			tf.grabFocus();
			return false;
		}

		return true;
	}

}

疾風亦有歸途
答案时间：2021-08-16

優化後的完整版

代码超过 5行，点击查看

/*
增加按钮:出现一个JDialog，在JDialog中进行增加
删除按钮:点击删除按钮之后，删除选中的行，并且刷新table中的数据，然后再默认选中第一行。
编辑按钮:点击的时候，弹出一个JDialog，显示选中的数据，并且能够修改。
      首选判断数据是否正确，是否为空，是否为数字等。 
      通过校验后，把数据保存到数据库，然后刷新table中的数据，并且选中第一条。

分页按钮:
在table中仅仅显示10条数据。在下方出现4个按钮
首页 上一页 下一页 末页
末页如果数据库中的总数能够整除10，那么最后一页就显示10个，否则就显示不到除以10的余数。 比如一共是25个，那么最后一页就显示5个。
如果有下一页的数据，才能点击下一页，否则下一页按钮是不可用的。通过如下代码设置代码不可用:
JButton.setEnable(false)
对首页，上一页和末页也是一样。

借助下拉框实现下拉框分页
*/

package swingtable02;

import java.awt.BorderLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.ListSelectionModel;

public class Test01 {

	// 把 htm和 table设计为静态，后面在更新表格数据的时候，就很容易访问这个两个对象
	static HeroTableModel htm = new HeroTableModel();
	static JTable t = new JTable(htm);
	static JComboBox<String> cb;
	static JButton bHome = new JButton("首頁");
	static JButton bPre = new JButton("上一頁");
	static JButton bNext = new JButton("下一頁");
	static JButton bEnd = new JButton("尾頁");
	static int number = 10;// 每页显示10个
	static int start = 0;// 开始的页码

	public static void main(String[] args) {

		final JFrame f = new JFrame();
		f.setSize(400, 330);
		f.setLocation(200, 200);
		f.setLayout(new BorderLayout());
		t.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
		t.getSelectionModel().setSelectionInterval(0, 0);
		JScrollPane sp = new JScrollPane(t);// 帶滾動條

		JPanel pOperation = new JPanel();
		JButton bAdd = new JButton("增加");
		JButton bDel = new JButton("刪除");
		JButton bEdt = new JButton("修改");
		pOperation.add(bAdd);
		pOperation.add(bDel);
		pOperation.add(bEdt);

		// 下拉框頁數
		JPanel Pagination = new JPanel();
		String[] comboBoxItems = new String[new HeroDAO().getTotal()];
		for (int i = 0; i < comboBoxItems.length; i++) {
			comboBoxItems[i] = Integer.toString(i);
		}
		cb = new JComboBox<>(comboBoxItems);

		Pagination.add(bHome);
		Pagination.add(bPre);
		Pagination.add(cb);
		Pagination.add(bNext);
		Pagination.add(bEnd);

		f.setLayout(null);
		sp.setBounds(0, 0, 394, 200);
		pOperation.setBounds(0, 200, 394, 50);
		Pagination.setBounds(0, 250, 394, 200);
		f.add(sp);
		f.add(pOperation);
		f.add(Pagination);
		updateButtonStatus();
		f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		f.setVisible(true);

		// 增加按鈕監聽器
		bAdd.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				new AddDialog(f).setVisible(true);// 放到函數中再設置
			}
		});

		// 刪除按鈕監聽器
		bDel.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				new DelDialog(f).setVisible(true);
			}
		});

		// 編輯按鈕監聽器
		bEdt.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				new EdtDialog(f).setVisible(true);
			}
		});

		// 首頁按鈕監聽器
		bHome.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start = 0;
				updateTable();
				updateButtonStatus();
			}
		});

		// 上一頁按鈕監聽器
		bPre.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start -= number;
				updateTable();
				updateButtonStatus();
			}
		});

		// 下一頁按鈕監聽器
		bNext.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start += number;
				updateTable();
				updateButtonStatus();
			}
		});

		// 尾頁按鈕監聽器
		bEnd.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				start = last();
				updateTable();
				updateButtonStatus();
			}
		});

		// 下拉框監聽器
		cb.addItemListener(new ItemListener() {
			@Override
			public void itemStateChanged(ItemEvent evt) {
				if (evt.getSource() == cb) {
					if (evt.getStateChange() == ItemEvent.SELECTED) {
						int s = Integer.parseInt((String) cb.getSelectedItem());
						start = s * number;
						updateTable();
						updateButtonStatus();
					}
				}
			}
		});
	}

	private static void updateButtonStatus() {
		int last = last();
		// 是否有上一页
		if (0 != start) {
			bHome.setEnabled(true);
			bPre.setEnabled(true);
		}

		// 是否是第一页
		if (0 == start) {
			bHome.setEnabled(false);
			bPre.setEnabled(false);
		}

		// 是否是最后一页
		if (start == last) {
			bEnd.setEnabled(false);
			bNext.setEnabled(false);
		}
		// 是否有下一页
		if (start != last) {
			bEnd.setEnabled(true);
			bNext.setEnabled(true);
		}
		
	  cb.setSelectedIndex(start/number);//按照序號設置JComboBox裡面的選項
	  
	}

	private static int last() {
		// 最后一页开始的位置
		int last;
		int total = new HeroDAO().getTotal();
		// 最后一页要看总數是否能够整除每页显示的数量number
		if (0 == total % number) {
			// 假设总数是20，那么最后一页开始的位置就是10
			last = total - number;
		} else {
			// 假设总数是21，那么最后一页开始的位置就是20
			last = total - total % number;
		}
		return last;
	}

	// 增加
	@SuppressWarnings("serial")
	static class AddDialog extends JDialog {
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");
		JTextField tfName = new JTextField();
		JTextField tfHp = new JTextField();
		JButton bSubmit = new JButton("提交");

		AddDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);
			pSubmit.add(bSubmit);
			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());
							Hero h = new Hero();
							h.name = name;
							h.hp = hp;
							new HeroDAO().add(h);
							JOptionPane.showMessageDialog(f, "提交成功");
							AddDialog.this.setVisible(false);
							updateTable();
							updateButtonStatus();
						}
					}

				}
			});

		}
	}

	// 刪除
	@SuppressWarnings("serial")
	static class DelDialog extends JDialog {
		JLabel sure = new JLabel("確定要刪除嗎");

		JButton byes = new JButton("是");
		JButton bno = new JButton("否");
		JButton bback = new JButton("取消");

		DelDialog(JFrame f) {
			super(f);
			this.setModal(true);
			this.setLayout(null);

			JPanel pSubmit = new JPanel();
			JPanel bSubmit = new JPanel();

			pSubmit.add(byes);
			pSubmit.add(bno);
			pSubmit.add(bback);
			bSubmit.add(sure);

			pSubmit.setBounds(0, 40, 300, 150);
			bSubmit.setBounds(0, 20, 300, 150);
			this.add(pSubmit);
			this.add(bSubmit);
			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			
			byes.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					int row = t.getSelectedRow();
					// 根据选中的行，到HeroTableModel中获取对应的对象
					int id = htm.heros.get(row).getId();
					HeroDAO dao = new HeroDAO();
					dao.delete(id);
					DelDialog.this.setVisible(false);
					if(start==new HeroDAO().getTotal()) {
					start=start-number;
					updateTable();
					updateButtonStatus();
					}
				
				}
			});
			
			bno.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					DelDialog.this.setVisible(false);
				}
			});

			bback.addActionListener(new ActionListener() {
				@Override
				public void actionPerformed(ActionEvent e) {
					DelDialog.this.setVisible(false);
					updateTable();
				}
			});

		}
	}

	// 修改
	@SuppressWarnings("serial")
	static class EdtDialog extends JDialog {
		int row = t.getSelectedRow();
		// 根据选中的行，到HeroTableModel中获取对应的对象
		Hero h = htm.heros.get(row);
		JLabel lName = new JLabel("名称");
		JLabel lHp = new JLabel("血量");

		JTextField tfName = new JTextField(h.name);
		JTextField tfHp = new JTextField(Float.toString(h.hp));

		JButton bSubmit = new JButton("提交");

		EdtDialog(JFrame f) {
			super(f);
			this.setModal(true);
			int gap = 50;
			this.setLayout(null);

			JPanel pInput = new JPanel();
			JPanel pSubmit = new JPanel();

			pInput.setLayout(new GridLayout(2, 2, gap, gap));
			pInput.add(lName);
			pInput.add(tfName);
			pInput.add(lHp);
			pInput.add(tfHp);
			pSubmit.add(bSubmit);

			pInput.setBounds(50, 20, 200, 100);
			pSubmit.setBounds(0, 130, 300, 150);

			this.add(pInput);
			this.add(pSubmit);

			this.setSize(300, 200);
			this.setLocationRelativeTo(f);
			bSubmit.addActionListener(new ActionListener() {

				@Override
				public void actionPerformed(ActionEvent e) {
					if (checkEmpty(tfName, "名称")) {
						if (checkNumber(tfHp, "hp")) {
							String name = tfName.getText();
							int hp = Integer.parseInt(tfHp.getText());
							new HeroDAO().add(h);
							JOptionPane.showMessageDialog(f, "提交成功");
							EdtDialog.this.setVisible(false);
							updateTable();
							updateButtonStatus();
						}
					}
				}
			});
		}
	}

	public static void updateTable() {
		htm.heros = new HeroDAO().list(start, number);
		t.updateUI();
		if (!htm.heros.isEmpty())
			t.getSelectionModel().setSelectionInterval(0, 0);
	}

	private static boolean checkEmpty(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + "不能为空");
			tf.grabFocus();
			return false;
		}
		return true;
	}

	private static boolean checkNumber(JTextField tf, String msg) {
		String value = tf.getText();
		if (0 == value.length()) {
			JOptionPane.showMessageDialog(null, msg + "不能为空");
			tf.grabFocus();
			return false;
		}
		try {
			Integer.parseInt(value);
		} catch (NumberFormatException e) {
			JOptionPane.showMessageDialog(null, msg + "只能是整数");
			tf.grabFocus();
			return false;
		}

		return true;
	}

}

沐紫灬
答案时间：2021-03-22

htm的mians是怎么设置的？

回答已经提交成功，正在审核。请于我的回答处查看回答记录，谢谢

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