Question

我是java开发的新手，并决定创建一个简单的java项目，输出鼠标在jframe内部的X和Y坐标。我不确定如何使用听众。

package main;

import java.awt.BorderLayout;
import java.awt.MouseInfo;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.SwingConstants;

public class Main {
public static void main(String[] args) {
jFrame();
}

public static void jFrame() {
    JFrame myFrame = new JFrame("Screen Location");
    myFrame.setVisible(true);
    myFrame.setBounds(0, 0, 300, 100);
    JLabel myText = new JLabel(""+ getTotal(),
        SwingConstants.CENTER);
    myFrame.getContentPane().add(myText, BorderLayout.CENTER);
}

private static String getTotal() {
    for (int i = 0; i < 1;) {
    int publicScreenValueX = MouseInfo.getPointerInfo().getLocation().x;
    int publicScreenValueY = MouseInfo.getPointerInfo().getLocation().y;
    String total = new String(publicScreenValueX + ", " + publicScreenValueY);
    return total;
    }
return null;
  }
}

我怎样才能让项目不断更新坐标？有人可以提供如何做到这一点的参考吗？

请注意，除了移动鼠标外，没有使用按钮，也没有使用任何输入。

以下是这样的图像：

除了坐标总是会更新。

Answer 1

基本上，为了创建处理鼠标事件的JFrame，您所要做的就是：

1 - 创建一个扩展JFrame并实现MouseListener

的类

2 - @Override mouseClicked，mouseEntered，mouseExited，mousePressed，mouseReleased监视相应的事件。现在，每当发生这些事件中的一个时，相应的功能将启动。使用MouseEvent.getX（），MouseEvent.getY（）来获取鼠标事件发生的窗口的坐标。

import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JFrame;

public class CreateJFrameWindowWithMouseEventHandling extends JFrame implements MouseListener {

    private static final long serialVersionUID = 1L;

    public CreateJFrameWindowWithMouseEventHandling() {
        setTitle("Simple Frame");
        addMouseListener(this);
    }

    @Override
    public void mouseClicked(MouseEvent e) {
        int x = e.getX();
        int y = e.getY();
        JOptionPane.showMessageDialog(null, "Mouse Clicked at X: " + String.valueOf(x) + " - Y: " + String.valueOf(y));
    }

    @Override
    public void mouseEntered(MouseEvent e) {
        int x = e.getX();
        int y = e.getY();
        System.out.println("Mouse Entered frame at X: " + x + " - Y: " + y);
    }

    @Override
    public void mouseExited(MouseEvent e) {
        int x = e.getX();
        int y = e.getY();
        System.out.println("Mouse Exited frame at X: " + x + " - Y: " + y);
    }

    @Override
    public void mousePressed(MouseEvent e) {
        int x = e.getX();
        int y = e.getY();
        System.out.println("Mouse Pressed at X: " + x + " - Y: " + y);
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        int x = e.getX();
        int y = e.getY();
        System.out.println("Mouse Released at X: " + x + " - Y: " + y);
    }

    private static void createAndShowGUI() {

  //Create and set up the window.

  JFrame frame = new CreateJFrameWindowWithMouseEventHandling();

  //Display the window.

  frame.setVisible(true);

  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    }

    public static void main(String[] args) {

  //Schedule a job for the event-dispatching thread:

  //creating and showing this application's GUI.

  javax.swing.SwingUtilities.invokeLater(new Runnable() {

public void run() {

    createAndShowGUI(); 

}

  });
    }

}

Answer 2

我建议创建一个继承自JFrame的新类以及所有这些，因为它更加面向对象友好。但是，使用您的代码，您需要做的是向您的JFrame添加MouseMotionListener，实现所有抽象方法，并在方法mouseMoved上更改您的myText标签文本; 将此方法替换为您当前拥有的方法，它应该可以工作。请注意，java.awt.event.MouseMotionListener仅向您提供有关应用程序窗口内鼠标移动的信息。对于在该窗口之外发生的事件，您可能想要检查另一个问题： Java mouse motion anywhere on screen

public static void jFrame() {
    JFrame myFrame = new JFrame("Screen Location");
    myFrame.setLocationRelativeTo(null);
    myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // makes the application close when you close the JFrame
    myFrame.setVisible(true);
    myFrame.setBounds(0, 0, 300, 100);
    JLabel myText = new JLabel(""+ getTotal(), SwingConstants.CENTER);
    myFrame.getContentPane().add(myText, BorderLayout.CENTER);
    myFrame.addMouseMotionListener(new MouseMotionListener(){
        @Override
        public void mouseDragged(MouseEvent e) {
            // don't delete this method
            // all abstract methods must be overridden 
        }

        @Override
        public void mouseMoved(MouseEvent e) {
            myText.setText(getTotal());
        }
    });

}

不断更新JFrame文本

2 个答案: