exercise12_5.java

来自「Introduction to java programming 一书中所有编程」· Java 代码 · 共 42 行

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Exercise12_5 extends JFrame  {
    
    public Exercise12_5() {
        getContentPane().add(new MyPanel());
    }
    
    public static void main(String[] args) {
        Exercise12_5 frame = new Exercise12_5();
        frame.setSize(200, 200);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
}

class MyPanel extends JPanel implements MouseListener {
    MyPanel() {
                
        this.addMouseListener(this);
    }
    
    public void mouseClicked(java.awt.event.MouseEvent mouseEvent) {
    }
    
    public void mouseEntered(java.awt.event.MouseEvent mouseEvent) {
    }
    
    public void mouseExited(java.awt.event.MouseEvent mouseEvent) {
    }
    
    public void mousePressed(java.awt.event.MouseEvent mouseEvent) {
        this.setBackground(Color.BLACK);
    }
    
    public void mouseReleased(java.awt.event.MouseEvent mouseEvent) {
        this.setBackground(Color.WHITE);
    }
}