Question

我试图使用箭头键移动一个盒子，但我似乎无法让它响应我的键：/。我看了几个教程来做到这一点，我不明白为什么我的代码不起作用。

基本上我试图让这个盒子像经典乒乓球游戏一样，除了它在底部，它只在X轴上移动。

如果有人能发现为什么我的盒子没有回应我的关键事件，我真的很感激=）我有2个类，主要和类包含＆＃34;播放器＆＃34;，这是盒子。

主：

package com.company;

import javax.swing.*;
import java.awt.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

public class Main extends JPanel implements KeyListener {

    Player player;

    Main() {
        player = new Player();
        this.addKeyListener(this);
        this.requestFocusInWindow();
    }

    public void update() {

        player.move();    
        this.repaint(); //runs the paint method on the object
    }

    @Override
    public void paint(Graphics g) {
        super.paint(g);
        player.paint(g);
    }

    public static void main(String[] args) {

        int width = 800;
        int height = 600;

        JFrame frame = new JFrame("Pinball"); //create a new window and set title on window
        frame.setSize(width, height); //set size of window
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //set the window to close when the cross in the corner is pressed
        Main m = new Main(width,height-22); //-22 to account for menubar height //create a new object and runs constructor for initial setup of the program
        frame.add(m); //add the content of the object to the window
        frame.setVisible(true); //make the window visible

        while (true) { //keep running a loop
            //each time the loop is run do
            m.update(); //run the update method on the object
            try {
                Thread.sleep(10); //stops this part of the program for 10 milliseconds to avoid the loop locking everything. Now the screen has time to update content etc.
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }

    }

    @Override
    public void keyTyped(KeyEvent e) {

    }

    @Override
    public void keyPressed(KeyEvent e) {
        int code = e.getKeyCode();
        if(code==KeyEvent.VK_RIGHT){
            player.setRight(true);
        }
        else if(code==KeyEvent.VK_LEFT){
            player.setLeft(true);
        }

    }

    @Override
    public void keyReleased(KeyEvent e) {

    }
}

播放器：

package com.company;


import java.awt.*;

/**
 * Created by John on 13/03/2015.
 */
public class Player {
private Boolean left = false, right = false;
    int xPos=200;     
    Player() {

    }


    public void move(){
        if(left){
            xPos-=2;
        }

        else if(right){
            xPos+=2;
        }
    }


    public void paint(Graphics g){
        g.fillRect(xPos,500,20,20);
    }

    public void setLeft(Boolean b){
        left=b;
    }

    public void setRight(Boolean b){
        right=b;
    }

}

KeyListener没有处理我的对象

0 个答案: