键盘控制小游戏简化版（功能添加更新。。），小游戏简化版

键盘控制小游戏简化版（功能添加更新。。），小游戏简化版

JAVA入门级小程序，个人感觉可以引发外行人对JAVA产生一些兴趣，如果我刚接触JAVA的时候能碰到这种程序就好了，我就不会这么被动的学JAVA了，到现在也学的很零散，没能形成系统知识。兴趣是最好的老师。努力学习JAVA中。。。

      以下贴出代码，附有程序运行结果图。所用代码均只用作演示，存在不少缺陷。

        实现了键盘方向键控制的最简单的球的移动及边缘判定，打印出球的实时坐标。

/**
 * 
 */
package ballgame;

import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

/**
 * 2014-6-11
 * 
 * @author Gelar
 */

public class BallGame extends Frame {

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	Image ball = Toolkit.getDefaultToolkit().getImage("images/ball.jpg");

	double x = 250;
	double y = 200;
	double xCoord = 250;
	double yCoord = 200;
	boolean left, right, up, down;

	public void paint(Graphics g) {
		g.drawImage(ball, (int) x, (int) y, null);
		if (left && x > 0) {
			x = x - 10;
			xCoord = x;
			printCoords();
		}
		if (right && x < 470) {
			x = x + 10;
			xCoord = x;
			printCoords();
		}
		if (up && y > 30) {
			y = y - 10;
			yCoord = y;
			printCoords();
		}
		if (down && y < 370) {
			y = y + 10;
			yCoord = y;
			printCoords();
		}
	}

	void launchFrame() {
		setSize(500, 400);
		setLocation(420, 170);
		setBackground(Color.black);
		setTitle("Ball Game");
		setVisible(true);
		new PaintThread().start();
		addKeyListener(new KeyMonitor());
		printInitialCoords();
	}

	void printInitialCoords() {
		System.out.println("(250.0,200.0)");
	}

	void printCoords() {
		if (left || right || up || down) {
			System.out.println("(" + xCoord + "," + yCoord + ")");
		}
	}

	public static void main(String[] args) {
		new BallGame().launchFrame();
	}

	class PaintThread extends Thread {
		public void run() {
			while (true) {
				repaint();
				try {
					Thread.sleep(200);
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
		}
	}

	class KeyMonitor extends KeyAdapter {
		public void keyPressed(KeyEvent e) {
			if (37 == e.getKeyCode()) {
				left = true;
			}
			if (39 == e.getKeyCode()) {
				right = true;
			}
			if (38 == e.getKeyCode()) {
				up = true;
			}
			if (40 == e.getKeyCode()) {
				down = true;
			}
		}

		public void keyReleased(KeyEvent e) {
			if (37 == e.getKeyCode()) {
				left = false;
			}
			if (39 == e.getKeyCode()) {
				right = false;
			}
			if (38 == e.getKeyCode()) {
				up = false;
			}
			if (40 == e.getKeyCode()) {
				down = false;
			}
		}
	}
}