如何同时收听多个按键输入 [英] How do I have multiple key inputs Listened to at the same time
问题描述
我正在尝试用 Java 创建一个简单的乒乓球游戏，但我不知道如何让两个玩家同时使用键盘.游戏是不完整的，我目前正在为两个玩家研究桨的运动.问题是，当一个玩家按下他们的向上键并向上移动他们的桨时，但如果其他玩家击中他们的任何一个键，它会取消之前玩家的动作并导致桨停止.我想我需要一种方法来同时处理多个键输入.这是我的代码，底部的 KeyListeners 是我需要帮助的地方.我只是一个 1 年的 Java 程序员，所以我的其余代码很容易.
I'm attempting to create a simple pong game in Java, but I don't know how to have both players using the keyboard at the same time. The game is incomplete and I'm working on the paddle movement for both players currently. The problem is, when a player pushes their up key and moves their paddle up, but if the other players hits any of their keys it cancels the previous players action and causes the paddle to stop. I think I need a way to handle multiple key inputs at once. Here's my code the KeyListeners at the bottom is where I need help. I'm only a 1 year Java programmer so go easy on the rest of my code.
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.HashSet;
import java.util.Set;
public class DrawGame extends JPanel implements ActionListener{
public static final int XPOS = 0;
public static final int YPOS = 0;
public boolean xFlag = true; // true means ballx is going right
public boolean yFlag = true; // true means bally is going down
public int ballX = 300; // Ball starting point
public int ballY = 400; // Ball starting point
Timer ballTimer; // Starts balls animation
public int leftScore;
public int rightScore;
public int rightPadY; // Right players paddle position
public int leftPadY; // left players paddle position
// Constructor
public DrawGame(){
addKeyListener(new RightListener());
addKeyListener(new LeftListener());
leftScore = 0;
rightScore = 0;
rightPadY = YPOS + 230;
leftPadY = YPOS + 230;
setBackground(Color.BLACK);
setPreferredSize(new Dimension(800, 600));
setFocusable(true);
ballTimer = new Timer(10, this);
ballTimer.start();
}
// Draws game
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2d = (Graphics2D)g;
//Drawing Side Boards
g2d.setColor(Color.WHITE);
g2d.fillRect(XPOS + 5, YPOS + 20, 775, 25); // Top Board
g2d.fillRect(XPOS + 5, YPOS + 517, 775, 25); // Bottom board
//Drawing the center line
g2d.fillRect(XPOS + 377, YPOS + 45 * 1, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 2, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 3, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 4, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 5, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 6, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 7, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 8, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 9, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 10, 25, 25);
g2d.fillRect(XPOS + 377, YPOS + 45 * 11, 25, 25);
//Drawing the paddles
g2d.fillRect(XPOS + 10, leftPadY, 20, 100);// Left
g2d.fillRect(XPOS + 755, rightPadY, 20, 100); // Right
//Drawing the ball
g2d.fillRect(ballX, ballY, 23, 23);
//Drawing the score
switch(leftScore){
case 0:
g2d.fillRect(XPOS + 305, YPOS + 50, 7, 30);
g2d.fillRect(XPOS + 325, YPOS + 50, 7, 30);
g2d.fillRect(XPOS + 305, YPOS + 50, 25, 7);
g2d.fillRect(XPOS + 305, YPOS + 80, 27, 7);
break;
case 1:
g2d.fillRect(XPOS + 325, YPOS + 50, 7, 30);
}
switch(rightScore){
case 0:
g2d.fillRect(XPOS + 450, YPOS + 50, 7, 30);
g2d.fillRect(XPOS + 470, YPOS + 50, 7, 30);
g2d.fillRect(XPOS + 450, YPOS + 50, 25, 7);
g2d.fillRect(XPOS + 450, YPOS + 80, 27, 7);
break;
case 1:
g2d.fillRect(XPOS + 450, YPOS + 50, 7, 30);
}
}
// Controls the animation of the ball
public void actionPerformed(ActionEvent e){
if(xFlag == true && ballX >= 735){
ballX += 2;
xFlag = false;
} else if(xFlag == true){
ballX += 2;
}
if(xFlag == false && ballX <= 25){
ballX -= 2;
xFlag = true;
} else if(xFlag == false){
ballX -= 2;
}
if(yFlag == true && ballY >= 500){
ballY += 2;
yFlag = false;
} else if(yFlag == true){
ballY += 2;
}
if(yFlag == false && ballY <= 45){
ballY -= 2;
yFlag = true;
} else if(yFlag == false){
ballY -= 2;
}
repaint();
ballTimer.restart();
}
// Keylistener for right player
private class RightListener implements KeyListener{
@Override
public synchronized void keyPressed(KeyEvent event) {
if(event.getKeyCode() == KeyEvent.VK_UP){
rightPadY -= 5;
}else if(event.getKeyCode() == KeyEvent.VK_DOWN){
rightPadY += 5;
}
repaint();
}
@Override
public synchronized void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
}
@Override
public synchronized void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub
}
}
// Keylistener for left player
private class LeftListener implements KeyListener{
@Override
public synchronized void keyPressed(KeyEvent event) {
if(event.getKeyCode() == KeyEvent.VK_W){
leftPadY -= 5;
} else if(event.getKeyCode() == KeyEvent.VK_S){
leftPadY += 5;
}
repaint();
}
@Override
public synchronized void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub
}
@Override
public synchronized void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub
}
}
}
推荐答案
不要使用 KeyListener.您应该使用 Key Bindings.
Don't use a KeyListener. You should be using Key Bindings.
有关详细信息，请参阅使用键盘进行动作.
See Motion Using the Keyboard for more information.
我将以下代码添加到上述链接中的 KeyboardAnimation 示例中，这将允许您执行所需的操作:
I added the following code to the KeyboardAnimation example from the above link, which will allow you to do what you want:
JLabel label2 = new JLabel( new ColorIcon(Color.GREEN, 40, 40) );
label2.setSize( label2.getPreferredSize() );
label2.setLocation(500, 500);
contentPane.add( label2 );
KeyboardAnimation animation2 = new KeyboardAnimation(label2, 24);
animation2.addAction("A", -3, 0);
animation2.addAction("D", 3, 0);
animation2.addAction("W", 0, -3);
animation2.addAction("S", 0, 3);
这篇关于如何同时收听多个按键输入的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
