MouseMotionListener 不适用于 Canvas

Question

这是我到目前为止的代码，我想做的是每次移动鼠标时添加一个新对象，但是经过数小时的思考，系统甚至没有访问 MouseEvent 类，我仍然无法弄清楚问题。请帮忙！！

我的主要课程：

  package testing;

import java.awt.Canvas;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.util.Random;

public class Wincall extends Canvas implements Runnable {

public static final int HEIGHT = 640, WIDTH = 1080;

private WinTest w;              
private Handler handler;
private ME me = new ME(this);

public Wincall(){

    handler = new Handler();
    w = new WinTest(WIDTH, HEIGHT, "Test", this);

}

public synchronized void run(){

    while(true){

        long now = System.currentTimeMillis();

        this.tick();  
        this.render();

        long after = System.currentTimeMillis();
        int tt = (int) (after-now);
        if(tt>5)
            try {
                Thread.sleep(10);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

        System.out.println("Time Taken in millisecs : " + tt);

    }

}

public void tick(){
    handler.tick();
}

public void render(){

    BufferStrategy bs = this.getBufferStrategy();
    if(bs == null)
    {
        this.createBufferStrategy(3);
        return;
    }
    Graphics g = bs.getDrawGraphics();

    //render

    g.setColor(Color.BLACK);
    g.fillRect(0 ,0 ,WIDTH, HEIGHT);


    handler.render(g);

    //render end

    g.dispose();
    bs.show();
}

public void addStuff(){

    handler.addObject(new TestGO(me.getX(), me.getY(), 32, 32));

}

public static void main(String[] args){
    new Wincall();
}
  }

我的 MouseEvent 类：

package testing;

import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;

public class ME implements MouseMotionListener{

private int mx = 0, my = 0;
private Wincall game;

public ME(Wincall game){
    this.game = game;
}

public void mouseDragged(MouseEvent e){}

public void mouseMoved(MouseEvent e) {

    game.addStuff();
    mx = e.getX();
    my = e.getY();

    System.out.println(mx);
    System.out.println(my);

}

public int getX(){
    return mx;
}

public int getY(){
    return my;
}

}

我的窗口类：

package testing;

import java.awt.Canvas;

import javax.swing.JFrame;

public class WinTest {

private static final long serialVersionUID = -369751247370351003L;

public WinTest(int h, int w, String title, Wincall game){

    JFrame f = new JFrame(title);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setSize(h, w);
    f.add(game);
    f.setVisible(true);
    f.requestFocus();
    f.setResizable(false);
    f.setFocusable(true);

    game.addMouseMotionListener(new ME());

    game.run();
}

}

Answer 1

虽然不清楚您要做什么。但是您需要将MouseMotionListener 添加到画布而不是JFrame。由于您将画布添加到 JFrame，因此应该捕获 MouseEvents 的是 canvas。因此，您的Wintest 应该看起来像这样：

public class WinTest extends Canvas {

private static final long serialVersionUID = -369751247370351003L;

public WinTest(int h, int w, String title, Wincall game, ME me) {

    JFrame f = new JFrame(title);
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.setSize(h, w);
    f.add(game);
    f.setVisible(true);
    f.requestFocus();
    f.setResizable(false);
    f.setFocusable(true);
    // f.addMouseMotionListener(me);
    game.addMouseMotionListener(me);
    game.run();
 }
}

更新：

Wincall 类：

public class Wincall extends Canvas implements Runnable {

public static final int HEIGHT = 640, WIDTH = 1080;

private WinTest w;
// private Handler handler;
private ME me = new ME(this);

public Wincall() {

    // handler = new Handler();
    w = new WinTest(WIDTH, HEIGHT, "Test", this, me);

}

public synchronized void run() {

    while (true) {

        long now = System.currentTimeMillis();

        this.tick();
        this.render();

        long after = System.currentTimeMillis();
        int tt = (int) (after - now);
        if (tt > 5)
            try {
                Thread.sleep(10);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

        // System.out.println("Time Taken in millisecs : " + tt);

    }

}

public void tick() {
    // handler.tick();
}

public void render() {

    BufferStrategy bs = this.getBufferStrategy();
    if (bs == null) {
        this.createBufferStrategy(3);
        return;
    }
    Graphics g = bs.getDrawGraphics();

    // render

    g.setColor(Color.BLACK);
    g.fillRect(0, 0, WIDTH, HEIGHT);

    // handler.render(g);

    // render end

    g.dispose();
    bs.show();
}

public void addStuff() {
    System.out.println("addStuff");
    // handler.addObject(new TestGO(me.getX(), me.getY(), 32, 32));

}

public static void main(String[] args) {
    new Wincall();
}
}

Answer 2

我正在查看我的一些旧源代码：

试试

addMouseMotionListener(我);

代替：

f.addMouseMotionListener(me);