MouseListener帮助Java [英] MouseListener Help Java

问题描述

我正在尝试用Java Swing编写一个程序，它输出一个10 x 10网格的几何矩形，里面装满了randoms颜色。但是，当用户单击显示窗口中的一个矩形时，矩形应重新绘制（）并更改为另一种颜色。

I am trying to write a program in Java Swing that outputs a 10 x 10 grid of geometric rectangles filled with randoms colors. However, when the user clicks on one of the rectangles within the display window the rectangle should repaint() and change to another color.

到目前为止，我已经运行了基本程序，但我无法弄清楚如何为它实现一个mouseListener，以便在用户使矩形颜色发生变化时点击里面。此时，矩形仅在显示窗口展开和最小化时重新绘制。任何建议/帮助将不胜感激！谢谢！

Thus far I have the rudimentary program running, but I can't figure out how to implement a mouseListener to it in order to have the rectangles' color change when a user clicks inside. At this point, the rectangles only repaint when the display window is expanded and minimized. Any advice/help would be greatly appreciated! Thanks!

这是我到目前为止所拥有的...

Here is what I have so far...

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


public class ColorGrid extends JPanel {
   int w, x, y, z;
   Color c = new Color((int)(Math.random() * 0xFFFFFF));
   public void paint(Graphics g){
   Graphics2D g2 = (Graphics2D) g;

   setLayout(new GridLayout(10,10));

   int w = x = y = z = 0;
   for(int i=0;i<100;i++){
   Color c = new Color((int)(Math.random() * 0xFFFFFF));
   w+=10;
   x+=10;
   y+=50;
   z+=15; 

          g2.drawRect(w+10,x+30,y,z);
          g2.drawRect(w+10,x+30,y,z);               
          g2.fillRect(w+10,x+30,y,z);
          g2.setPaint(c);  
        } 
   }

   public static void main(String[] args) {
      JFrame f= new JFrame();
      f.setTitle("ColorGrid Display Window");
      f.setSize(200,200);
      f.addWindowListener(new WindowAdapter() {
          public void windowClosing(WindowEvent e) {
          System.exit(0);
          }
    });
    Container contentPane = f.getContentPane();
    contentPane.add(new ColorGrid());
    f.show();
    }
}

推荐答案

任何组件可以有一个 MouseListener 。 JLabel 非常适合彩色矩形，只要你让它变得不透明。

Any Component can have a MouseListener. JLabel is nice for a colored rectangle, as long as you make it opaque.

附录：推荐 MouseAdapter 在其他地方，我应该提到一个实例已足够。

Addendum: Having recommended MouseAdapter elsewhere, I should mention that one instance is enough.

附录：此更新添加 ColorLabel 构造函数中的鼠标侦听器。

Addendum: This update adds the mouse listener in the ColorLabel constructor.

import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JLabel;

/** @see http://stackoverflow.com/questions/5136859 */
public class ColorLabel extends JLabel {

    private static final int N = 10;
    private static final Random random = new Random();
    private static final MouseAdapter listener = new MouseAdapter() {

        @Override
        public void mousePressed(MouseEvent e) {
            ColorLabel label = (ColorLabel) e.getSource();
            label.setBackground(new Color(random.nextInt()));
        }
    };

    public ColorLabel() {
        this.setOpaque(true);
        this.setBackground(new Color(random.nextInt()));
        this.setPreferredSize(new Dimension(32, 32));
        this.addMouseListener(listener);
    }

    private void displayGrid() {
        JFrame f = new JFrame("ColorGrid");
        f.setLayout(new GridLayout(N, N));
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        for (int i = 0; i < N * N; i++) {
            final ColorLabel label = new ColorLabel();
            f.add(label);
        }
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
    }

    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                new ColorLabel().displayGrid();
            }
        });
    }
}

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