Question

我遇到了让鼠标事件发挥作用的问题。我在JLayeredPane里面有一个JPanel，它位于JScrollPane中。不可否认，我对使用Swing很新，但基本上，我希望JPanel能够对鼠标移动作出反应，但却无法让它发挥作用。

public class CellHighlighter extends JPanel implements MouseMotionListener{

    public CellHighlighter(){

    }

    public void mouseMoved(MouseEvent evt){
        System.out.println(evt.getPoint().x + ", " + evt.getPoint().y);
    }

    public void mouseDragged(MouseEvent evt){System.out.println("message");}

}

非常感谢任何帮助，提前谢谢！

Answer 1

您是否使用MouseListener注册JPanel对象？类似的东西：

    public CellHighlighter(){
       this.addMouseMotionListener(this);
    }

或者您可能需要将MouseListener添加到ScrollPane或LayeredPane？

Answer 2

以下是您可以使用的一些演示代码：

import java.awt.Color;
import java.awt.Dimension;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class ReactPanel extends JPanel implements MouseMotionListener {

    public ReactPanel(){
        setPreferredSize(new Dimension(450, 450));
        setBackground(Color.GREEN);
        addMouseMotionListener(this);
    }

    @Override
    public void mouseDragged(MouseEvent e) {
        System.out.println("Mouse dragged (" + e.getX() + ',' + e.getY() + ')');
    }

    @Override
    public void mouseMoved(MouseEvent e) {
        System.out.println("Mouse moved (" + e.getX() + ',' + e.getY() + ')');

    }

    public static void main(String[] args){
        //Create and set up the window.
        JFrame frame = new JFrame("MouseMotionEventDemo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        //Create and set up the content pane.
        JComponent newContentPane = new ReactPanel();
        newContentPane.setOpaque(true); //content panes must be opaque
        frame.setContentPane(newContentPane);

        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }
}

鼠标在JPanel中移动了事件

2 个答案: