在 Java 中检查鼠标是否被点击

Checking if the mouse is clicked in Java

提问by MezuCobalt

I am writing a GUI in Java. I need to know how to check if the user clicks the mouse. I know how to check the position of the mouse, but I just need to check if it's clicked.

我正在用 Java 编写 GUI。我需要知道如何检查用户是否点击了鼠标。我知道如何检查鼠标的位置，但我只需要检查它是否被点击。

import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
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import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;

import javax.imageio.*;
import javax.swing.*;

/**
 * This class demonstrates how to load an Image from an external file
 */
public class LoadImageApp extends Component {

    BufferedImage img;

    public void paint(Graphics g) {
        g.drawImage(img, 50, 70, null);
    }

    public LoadImageApp() {
       try {
           img = ImageIO.read(new File("strawberry.jpg"));
       } catch (IOException e) {
       }

    }

    public Dimension getPreferredSize() {
        if (img == null) {
             return new Dimension(100,100);
        } else {
           return new Dimension(img.getWidth(null), img.getHeight(null));
       }
    }

    public static void main(String[] args) throws InterruptedException {

        JFrame f = new JFrame("Load Image Sample");

        f.addWindowListener(new WindowAdapter(){
                public void windowClosing(WindowEvent e) {
                    System.exit(0);
                }
            });

        f.add(new LoadImageApp());
        f.pack();
        f.setVisible(true);
        f.setResizable(true);
        while(true){
            Thread.sleep(1000);
            PointerInfo a = MouseInfo.getPointerInfo();
            Point b = a.getLocation();
            int x = (int) b.getX();
            int y = (int) b.getY();

            System.out.println(x);
            System.out.println(y);
        }
        }
    public void mouseClicked(MouseEvent e) {
        System.out.println("mouseClicked");  
        }
}

this is all my code, so please just explain how to impliment that one mouse checker thing. Thanks!

这是我所有的代码，所以请解释如何实现鼠标检查器的东西。谢谢！

回答by Kon

Implement the MouseListenerinterface and put your code inside the mouseClicked(MouseEvent e)method. Then add an instance of this class as a listener to your component.

实现MouseListener接口并将您的代码放入mouseClicked(MouseEvent e)方法中。然后将此类的一个实例作为侦听器添加到您的组件中。

Basically, you create a class like this:

基本上，你创建一个这样的类：

class myMouseListener implements MouseListener {

    @Override
    public void mouseClicked(MouseEvent arg0) { 
       //Put the code you want here
       //...
       //...
     }

     @Override
     public void mouseEntered(MouseEvent arg0) { }

     @Override
     public void mouseExited(MouseEvent arg0) { }

     @Override
     public void mousePressed(MouseEvent arg0) { }

     @Override
     public void mouseReleased(MouseEvent arg0) { }

}

Then you simple create a new instance of this new class with myMouseListener

然后你简单地使用 myMouseListener 创建这个新类的新实例

myMouseListener mml = new myMouseListener();

And you add it as a listener to your component. Something like:

然后将其添加为组件的侦听器。就像是：

myPanel.addMouseListener(mml);

All information here: http://docs.oracle.com/javase/7/docs/api/java/awt/event/MouseListener.html

这里的所有信息：http: //docs.oracle.com/javase/7/docs/api/java/awt/event/MouseListener.html