package util;

import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.SwingWorker;

public class CircleProgressBar extends JPanel {

	private int minimumProgress;

	private int maximumProgress;

	private int progress;

	private String progressText;

	private Color backgroundColor;

	private Color foregroundColor;

	public CircleProgressBar() {
		minimumProgress = 0;
		maximumProgress = 100;
		progressText = "0%";
	}

	public void paint(Graphics g) {
		super.paint(g);
		Graphics2D graphics2d = (Graphics2D) g;
		// 开启抗锯齿
		graphics2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
		int x = 0;
		int y = 0;
		int width = 0;
		int height = 0;
		int fontSize = 0;
		if (getWidth() >= getHeight()) {
			x = (getWidth() - getHeight()) / 2 + 25;
			y = 25;
			width = getHeight() - 50;
			height = getHeight() - 50;
			fontSize = getWidth() / 8;
		} else {
			x = 25;
			y = (getHeight() - getWidth()) / 2 + 25;
			width = getWidth() - 50;
			height = getWidth() - 50;
			fontSize = getHeight() / 8;
		}
		graphics2d.setStroke(new BasicStroke(20.0f));
		graphics2d.setColor(backgroundColor);
		graphics2d.drawArc(x, y, width, height, 0, 360);
		graphics2d.setColor(foregroundColor);
		graphics2d.drawArc(x, y, width, height, 90,
				-(int) (360 * ((progress * 1.0) / (maximumProgress - minimumProgress))));
		graphics2d.setFont(new Font("黑体", Font.BOLD, fontSize));
		FontMetrics fontMetrics = graphics2d.getFontMetrics();
		int digitalWidth = fontMetrics.stringWidth(progressText);
		int digitalAscent = fontMetrics.getAscent();
		graphics2d.setColor(foregroundColor);
		graphics2d.drawString(progressText, getWidth() / 2 - digitalWidth / 2, getHeight() / 2 + digitalAscent / 2);
	}

	public int getProgress() {
		return progress;
	}

	public void setProgress(int progress) {
		if (progress >= minimumProgress && progress <= maximumProgress)
			this.progress = progress;
		if (progress > maximumProgress)
			this.progress = maximumProgress;

		this.progressText = String.valueOf(progress + "%");

		this.repaint();
	}

	public Color getBackgroundColor() {
		return backgroundColor;
	}

	public void setBackgroundColor(Color backgroundColor) {
		this.backgroundColor = backgroundColor;
		this.repaint();
	}

	public Color getForegroundColor() {
		return foregroundColor;
	}

	public void setForegroundColor(Color foregroundColor) {
		this.foregroundColor = foregroundColor;
		this.repaint();
	}

}

package test;
 
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
 
import javax.swing.JButton;
import javax.swing.JPanel;
import javax.swing.SwingWorker;
 
import util.CircleProgressBar;
import util.ColorUtil;
import util.GUIUtil;
 
public class Test {
    public static void main(String[] args) {
    	GUIUtil.useLNF();
        //面板
        JPanel p = new JPanel();
        //进度条组件
        CircleProgressBar cpb = new CircleProgressBar();
        cpb.setBackgroundColor(ColorUtil.blueColor);
        cpb.setProgress(0);
        //按钮
        JButton b = new JButton("点击");
        //添加组件
        p.setLayout(new BorderLayout());
        p.add(cpb, BorderLayout.CENTER);
        p.add(b, BorderLayout.SOUTH);
        //显示面板
        GUIUtil.showPanel(p);
         
        //给按钮加监听
        b.addActionListener(new ActionListener() {
 
            @Override
            public void actionPerformed(ActionEvent e) {
                new SwingWorker() {
 
                    @Override
                    protected Object doInBackground() throws Exception {
                        for (int i = 0; i < 100; i++) {
                            cpb.setProgress(i + 1);
                            cpb.setForegroundColor(ColorUtil.getByPercentage(i + 1));
                            try {
                                Thread.sleep(100);
                            } catch (InterruptedException e1) {
                                // TODO Auto-generated catch block
                                e1.printStackTrace();
                            }
                        }
                        return null;
                    }
 
                }.execute();
 
            }
        });     
 
    }
}