用java绘制一个窗体

用java绘制一个窗体

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JFrame;import javax.swing.JPanel;
@SuppressWarnings("serial")
public class Demo_mouseListener2 extends JFrame{

private MyPanel myPanel = null;

public Demo_mouseListener2(){
myPanel = new MyPanel();
this.add(myPanel,BorderLayout.CENTER);
myPanel.addMouseListener(myPanel);
this.setSize(400, 300);
this.setTitle("鼠标事件处理");
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
}

public static void main(String[] args) {
new Demo_mouseListener2();
}
class MyPanel extends JPanel implements MouseListener{
int x = 0;
int y = 0;
int buttonType = 0;
//鼠标点击
public void mouseClicked(MouseEvent e) {
x = e.getX();
y = e.getY();
buttonType = e.getButton();
//鼠标左键
Graphics g = this.getGraphics();

if(buttonType==1){
if(e.getClickCount()==2){
g.clearRect(0, 0, 400, 300);

}else if(e.getClickCount()==1){
g.setColor(Color.green);
g.fillOval(x, y, 20, 20);
}
}else if(buttonType ==3){
g.setColor(Color.red);
g.fillRect(x, y, 20, 20);

}
}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}
public void mousePressed(MouseEvent e) {}
public void mouseReleased(MouseEvent e) {}
}

}

afdsdfdsafd

别忘了引用swing、awt、awt里面的event
   

百度变态，不让贴原码