有什么方法可以使用Java中的Thread在JPanel上绘制图形吗？

Mamunur Rimon 发表于 Dev

马蒙努尔·里蒙（Mamunur Rimon）

在下面的代码中，我尝试通过绘制方法绘制一个椭圆，并从一个线程绘制另一个椭圆。但是，只有从paint方法绘制的椭圆形才会显示在JPanel上。如果不可能的话，请给其他想法。

import java.awt.Graphics;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Ani extends JPanel{

    public Ani(){
        JFrame jf = new JFrame();
        jf.setSize(555,555);
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jf.add(this);
        jf.setVisible(true);
    }

    public void paint(Graphics g){         
         g.fillOval(22,22, 55, 55);  
         Thread t = new Thread(new MyThread(g)); 
         t.start();
    }

    public static void main(String[] args) {
        new Ani();
    }

}

class MyThread extends Thread{
    Graphics g;
    MyThread(Graphics g){
        this.g = g; 
    }

    public void run(){
        g.fillOval(222, 222, 55, 55);       
    }
}

博士阿卜杜勒·巴里（Abdul Bari）|

试试这个

import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Ani2 extends JPanel implements Runnable{
private Thread animator;
int x=0, y=0;
private final int DELAY = 50;
    public Ani2(){
        JFrame jf = new JFrame();
        jf.setSize(555,555);
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jf.add(this);
        jf.setVisible(true);
    }

    @Override
    public void addNotify() {
        super.addNotify();
        animator = new Thread(this);
        animator.start();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2d = (Graphics2D)g;
        g2d.fillOval(x,y, 55, 55);
        g.dispose();
    }
    public void cycle() {

        x += 1;
        y += 1;
    }

    public static void main(String[] args) {
        new Ani2();
    }

    @Override
    public void run() {
        long beforeTime, timeDiff, sleep;

        beforeTime = System.currentTimeMillis();

        while (true) {

            cycle();
            repaint();

            timeDiff = System.currentTimeMillis() - beforeTime;
            sleep = DELAY - timeDiff;

            if (sleep < 0)
                sleep = 2;
            try {
                Thread.sleep(sleep);
            } catch (InterruptedException e) {
                System.out.println("interrupted");
            }

            beforeTime = System.currentTimeMillis();
        }
    }

}