Java坦克大战 (六) 之增加可玩性

本文来自：小易博客专栏。转载请注明出处：http://blog.csdn.net/oldinaction

在此小易将坦克大战这个项目分为几个版本，以此对J2SE的知识进行回顾和总结，希望这样也能给刚学完J2SE的小伙伴们一点启示！

坦克大战V0.6实现功能：

1、超级炮弹
2、我方坦克有生命值
3、图像化我方坦克的生命值
4、添加血块，吃了可以涨生命值
5、敌方坦克死完后可以再有新的加入，我方坦克死亡可以复活

注意事项：

1、画生命值是fillRect()和drawRect()的不同

2、此处血块的移动时自己定义成固定的，也可以随机，每次移动的距离不能太大，否则会闪烁

坦克大战V0.6源代码：

TankClient类：

import java.awt.*;
import java.awt.event.*;
import java.util.List; //java.awt包中也有个List，所以此处要导包明确
import java.util.ArrayList;

/**
 * 主要的类
 * @ClassName: TankClient
 * @Description: 坦克，子弹，爆炸，血块都在这里实例化
 * @author oldinaction
 * @date 2014年9月2日 下午4:15:44
 */
public class TankClient extends Frame {
	public static final int GAME_WIDTH = 800;
	public static final int GAME_HEIGHT = 600;

	Tank myTank = new Tank(350, 520, true, Tank.Direction.STOP, this); //我方坦克
	Wall w1 = new Wall(100, 300, 20, 100, this), w2 = new Wall(300, 250, 150, 20, this);
	Blood b = new Blood(this);

	List<Missile> missiles = new ArrayList<Missile>(); //定义一个集合来装子弹
	List<Explode> explodes = new ArrayList<Explode>();
	List<Tank> tanks = new ArrayList<Tank>();

	Image offScreenImage = null; //定义一个屏幕后的虚拟图片

	@Override
	public void paint(Graphics g) {
		if (tanks.size() <= 0) {
			for(int i = 0; i < 8; i++) {
				tanks.add(new Tank(50 + 40*(i+1), 50, false,Tank.Direction.D, this));
			}
		}

		g.drawString("missiles Count: " + missiles.size(), 10, 50); //用来记录missiles中子弹的个数
		g.drawString("explodes Count: " + explodes.size(), 10, 70);
		g.drawString("tanks Count: " + tanks.size(), 10, 90);
		g.drawString("myTank life: " + myTank.getLife(), 10, 110);

		for (int i = 0; i < missiles.size(); i++) { //遍历集合，把其中的子弹画出来
			Missile m = missiles.get(i);
			m.hitTanks(tanks);
			m.hitTank(myTank);
			m.hitWall(w1); //检测子弹是否撞墙
			m.hitWall(w2);
			m.drawMissile(g);
		}

		for (int i = 0; i < explodes.size(); i++) {
			Explode e = explodes.get(i);
			e.draw(g);
		}

		for (int i = 0; i < tanks.size(); i++) {
			Tank t = tanks.get(i);
			t.collidesWithWall(w1); //检测敌方坦克是否撞墙
			t.collidesWithWall(w2);
			t.collidesWithTanks(tanks);
			t.drawTank(g);
		}

		myTank.drawTank(g);
		myTank.eat(b);
		w1.draw(g);
		w2.draw(g);
		b.draw(g);
	}

	//利用双缓冲消除圆圈移动时屏幕的闪动
	@Override
	public void update(Graphics g) {
		if (offScreenImage == null) {
			offScreenImage = this.createImage(GAME_WIDTH, GAME_HEIGHT); //判断是为了避免每次重画时都给offScreenImage赋值
		}
		Graphics gOffScreen = offScreenImage.getGraphics(); //定义虚拟图片上的画笔gOffScreen
		Color c = gOffScreen.getColor();
		gOffScreen.setColor(Color.GREEN);
		gOffScreen.fillRect(0, 0, GAME_WIDTH, GAME_HEIGHT); //重画背景，如果没有这句则在屏幕上会保留圆圈的移动路径
		gOffScreen.setColor(c);
		paint(gOffScreen); //把圆圈画到虚拟图片上
		g.drawImage(offScreenImage, 0, 0, null); //再一次性把虚拟图片画到真实屏幕上，在真实屏幕上画则要用真实屏幕的画笔g
	}

	public void luanchFrame() {

		for(int i = 0; i < 10; i++) {
			tanks.add(new Tank(50 + 40*(i+1), 50, false,Tank.Direction.D, this));
		}

		this.setLocation(300, 50);
		this.setSize(GAME_WIDTH, GAME_HEIGHT);
		this.setTitle("坦克大战 - By:小易 - QQ：381740148");
		this.setResizable(false); //不允许改变窗口大小
		this.addWindowListener(new WindowAdapter() {
			@Override
			public void windowClosing(WindowEvent e) {
				System.exit(0);
			}
		}); //添加关闭功能，此处使用匿名类比较合适
		this.setBackground(Color.GREEN);

		this.addKeyListener(new KeyMonitor());

		setVisible(true);

		new Thread(new PaintThread()).start(); //启动线程，实例化线程对象时不要忘了new Thread(Runnable对象);
	}

	public static void main(String[] args) {
		TankClient tc = new TankClient();
		tc.luanchFrame();
	}

	//PaintThread只为TankClient服务，所以写成内部类好些
	public class PaintThread implements Runnable { 

		public void run() {
			while (true) {
				repaint(); //repaint()是TankClient或者他的父类的方法，内部类可以访问外部包装类的成员，这也是内部类的好处
				try {
					Thread.sleep(50); //每隔50毫秒重画一次
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
		}
	}

	public class KeyMonitor extends KeyAdapter {

		@Override
		public void keyReleased(KeyEvent e) {
			myTank.keyReleased(e);
		}

		@Override
		public void keyPressed(KeyEvent e) {
			myTank.keyPressed(e);
		}
	}

}

Tank类：

import java.awt.*;
import java.awt.event.*;
import java.util.Random;

public class Tank {
	public static final int XSPEED = 5; //定义常量X轴速度
	public static final int YSPEED = 5;

	public static final int WIDTH = 30;
	public static final int HEIGHT = 30;

	public static final int LIFE = 100;

	//定义一个随机数产生器，此时的Random类是java.util.Random，不同于Math中的
	private static Random r = new Random(); //随机数产生器只需要一个，所以定义成静态，防止每次new一个坦克是都会产生一个随机数产生器
	private BloodBar bb = new BloodBar();

	private boolean good; //定义变量说明是我方还是敌方坦克，为true表示我方坦克

	private boolean live = true; //定义变量说明是坦克是否存活

	private int life = LIFE; //设置坦克的生命值为100

	TankClient tc;

	private int x , y; //定义变量画圆圈(坦克)时四边形左上点的x、y左边
	private int oldX , oldY; //定义坦克上个位置的坐标

	private boolean bL = false, bU = false, bR = false, bD = false; //定义变量左上右下的按键是否被按下
	enum Direction {L,LU,U,RU,R,RD,D,LD,STOP}; //定义枚举类型，值为左、左上、上、右上、右、右下、下、左下、停止

	private Direction dir = Direction.STOP; //定义变量坦克的方向
	private Direction ptDir = Direction.U; //定义变量坦克炮筒的方向，起初向上

	private int step = r.nextInt(12) + 3; //定义坦克朝着一个方向移动几步

	public Tank(int x, int y, boolean good) {
		this.x = x;
		this.y = y;
		this.good = good;
		this.oldX = x;
		this.oldY =y;
	}

	public Tank(int x, int y, boolean good, Direction dir, TankClient tc) {
		this(x, y, good); //相当于调用上面的构造方法
		this.dir = dir;
		this.tc = tc;
	}

	public void drawTank(Graphics g) {
		if(!live) {
			if(!good) {
				tc.tanks.remove(this);
			}
			return; //如果坦克没有存活就直接返回，不用画坦克了
		}

		Color c = g.getColor(); //取得g(以后称为画笔)的颜色
		if(good) g.setColor(Color.RED);
		else g.setColor(Color.BLUE);
		g.fillOval(x, y, WIDTH, HEIGHT); //"画圆",利用填充一个四边形(四边形的内切圆)，参数分别代表：四边形左上点的坐标X，Y，宽度，高度
		g.setColor(c); //用完画笔后把画笔默认的颜色(黑色)设置回去

		if (good) bb.draw(g);

		//根据炮筒的方向，画直线代表炮筒
		switch (ptDir) {
		case L:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x, y+Tank.HEIGHT/2);
			break;
		case LU:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x, y);
			break;
		case U:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x+Tank.WIDTH/2, y);
			break;
		case RU:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x+Tank.WIDTH, y);
			break;
		case R:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x+Tank.WIDTH, y+Tank.HEIGHT/2);
			break;
		case RD:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x+Tank.WIDTH, y+Tank.HEIGHT);
			break;
		case D:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x+Tank.WIDTH/2, y+Tank.HEIGHT);
			break;
		case LD:
			g.drawLine(x+Tank.WIDTH/2, y+Tank.HEIGHT/2, x, y+Tank.HEIGHT);
			break;
		}

		move(); //每次按键都会重画，就会调用drawTank，在这里重画坦克的此时位置
	}

	public void keyPressed(KeyEvent e) {
		int key = e.getKeyCode(); //得到按键的虚拟码，再和下面的KeyEvent.VK_LEFT等虚拟码比较看是否是某按键
		switch (key) {
		case KeyEvent.VK_F2:
			if (!this.live) {
				this.live = true;
				this.life = LIFE;
			}
			break;
		case KeyEvent.VK_LEFT:
			bL = true;
			break;
		case KeyEvent.VK_UP:
			bU = true;
			break;
		case KeyEvent.VK_RIGHT:
			bR = true;
			break;
		case KeyEvent.VK_DOWN:
			bD = true;
			break;
		}
		locateDraction();

		if (dir != Direction.STOP) {
			ptDir = dir;
		}
	}

	public void keyReleased(KeyEvent e) {
		int key = e.getKeyCode();
		switch (key) {
		case KeyEvent.VK_SPACE: //按SPACE就发射子弹调用fire方法
			fire(); //只有松开SPACE才能发出子弹
			break;
		case KeyEvent.VK_LEFT:
			bL = false;
			break;
		case KeyEvent.VK_UP:
			bU = false;
			break;
		case KeyEvent.VK_RIGHT:
			bR = false;
			break;
		case KeyEvent.VK_DOWN:
			bD = false;
			break;
		case KeyEvent.VK_CONTROL: //按Ctrl就发射子弹调用fire方法
			superFire();
			break;
		}
		locateDraction();
	}

	//通过上右下的按键是否被按下判断坦克要运动的方向
	void locateDraction() {
		if(bL && !bU && !bR && !bD) dir =Direction.L;
		else if(bL && bU && !bR && !bD) dir =Direction.LU;
		else if(!bL && bU && !bR && !bD) dir =Direction.U;
		else if(!bL && bU && bR && !bD) dir =Direction.RU;
		else if(!bL && !bU && bR && !bD) dir =Direction.R;
		else if(!bL && !bU && bR && bD) dir =Direction.RD;
		else if(!bL && !bU && !bR && bD) dir =Direction.D;
		else if(bL && !bU && !bR && bD) dir =Direction.LD;
		else if(!bL && !bU && !bR && !bD) dir =Direction.STOP;
	}

	public void move() {
		oldX = x;
		oldY = y;

		switch (dir) {
		case L:
			x -= XSPEED;
			break;
		case LU:
			x -= XSPEED;
			y -= YSPEED;
			break;
		case U:
			y -= YSPEED;
			break;
		case RU:
			x += XSPEED;
			y -= YSPEED;
			break;
		case R:
			x += XSPEED;
			break;
		case RD:
			x += XSPEED;
			y += YSPEED;
			break;
		case D:
			y += YSPEED;
			break;
		case LD:
			x -= XSPEED;
			y += YSPEED;
			break;
		case STOP:
			break;
		}

		if(this.dir != Direction.STOP) {
			this.ptDir = this.dir;
		}

		//防止坦克出界
		if (x < 0) x = 0;
		if (y < 25) y = 25; //考虑了标题栏的高度
		if (x + Tank.WIDTH > TankClient.GAME_WIDTH) x = TankClient.GAME_WIDTH - Tank.WIDTH;
		if (y + Tank.HEIGHT > TankClient.GAME_HEIGHT) y = TankClient.GAME_HEIGHT - Tank.HEIGHT;

		if (!good) {
			Direction[] dirs = Direction.values(); //把枚举转换成数组
			if (step == 0) {
				int rn = r.nextInt(dirs.length);
				dir = dirs[rn]; //如果移动步数为0就改变方向
				step = r.nextInt(12) + 3;
			}
			step --;

			if(r.nextInt(40) > 37) this.fire();
		}
	}

	public void stay() {
		x = oldX;
		y = oldY;
	}

	//坦克开火，就new一个子弹出来
	private Missile fire() {
		if(!live) return null;

		int x = this.x + Tank.WIDTH/2 - Missile.WIDTH/2; //让子弹从坦克中心打出
		int y = this.y + Tank.HEIGHT/2 - Missile.HEIGHT/2;
		Missile m = new Missile(x, y,good, ptDir , this.tc);
		tc.missiles.add(m); //每new一个Missile对象就把他装到集合中
		return m; //返回的m，其他地方可调用可不调用
	}

	private Missile fire(Direction dir) {
		if(!live) return null;

		int x = this.x + Tank.WIDTH/2 - Missile.WIDTH/2; //让子弹从坦克中心打出
		int y = this.y + Tank.HEIGHT/2 - Missile.HEIGHT/2;
		Missile m = new Missile(x, y,good, dir , this.tc);
		tc.missiles.add(m); //每new一个Missile对象就把他装到集合中
		return m; //返回的m，其他地方可调用可不调用
	}

	public Rectangle getRect() {
		return new Rectangle(x, y, WIDTH, HEIGHT); //得到坦克的探测方块，Rectangle是java.awt包中专门用于游戏碰撞的类
	}

	public boolean isLive() {
		return live;
	}

	//Tank类的成员方法可生成对应的get和set方法，那么在其他类中就可以访问了
	public void setLive(boolean live) {
		this.live = live;
	}

	public boolean isGood() {
		return good;
	}

	//检测坦克是否撞墙
	public boolean collidesWithWall(Wall w) {
		if(this.live && this.getRect().intersects(w.getRect())) {
			stay(); //如果坦克撞到墙就让他回到上一个位置
			return true;
		}
		return false;
	}

	//检测坦克是否相撞,java.util.List<E>接口或者类的另一种写法，java.awt中也有List，所以要写明确
	public boolean collidesWithTanks(java.util.List<Tank> tanks) {
		for (int i = 0; i < tanks.size(); i++) {
			Tank t = tanks.get(i);
			if (this != t) {
				if(this.live && t.isLive() && this.getRect().intersects(t.getRect())) {
					this.stay();
					t.stay();
					return true;
				}
			}
		}
		return false;
	}

	//超级炮弹：朝8个方向各发一发炮弹
	private void superFire() {
		Direction[] dirs = Direction.values();
		for (int i = 0; i < 8; i++) { //dirs[8]是STOP
			fire(dirs[i]);
		}
	}

	public int getLife() {
		return life;
	}

	public void setLife(int life) {
		this.life = life;
	}

	public class BloodBar {
		public void draw(Graphics g) {
			Color c = g.getColor();
			g.setColor(Color.RED);
			g.drawRect(x, y - 10, WIDTH, 10);
			int w = WIDTH * life/LIFE ;
			g.fillRect(x, y - 10, w, 10);
			g.setColor(c);
		}
	}

	//吃血块
	public boolean eat(Blood b) {
		if(this.live && b.isLive() && this.getRect().intersects(b.getRect())) {
			b.setLive(false);
			life = LIFE;
			return true;
		}
		return false;
	}
}

Missile类：

import java.awt.*;
import java.util.List;

public class Missile {
	public static final int XSPEED = 10;
	public static final int YSPEED = 10;

	public static final int WIDTH = 10;
	public static final int HEIGHT = 10;

	int x, y;
	Tank.Direction dir;

	private boolean good; //定义变量表示是否是我方子弹

	private boolean live = true; //定义一个判断子弹是否出界的变量

	private TankClient tc;

	public Missile(int x, int y, Tank.Direction dir) {
		this.x = x;
		this.y = y;
		this.dir = dir;
	}

	public Missile(int x, int y,boolean good, Tank.Direction dir, TankClient tc) {
		this(x, y, dir);
		this.good = good;
		this.tc = tc;
	}

	public void drawMissile(Graphics g) {
		if(!live) {
			tc.missiles.remove(this);
			return;
		}

		Color c = g.getColor();
		g.setColor(Color.BLACK);
		g.fillOval(x, y, WIDTH, HEIGHT);
		g.setColor(c);

		move();
	}

	private void move() {
		switch (dir) {
		case L:
			x -= XSPEED;
			break;
		case LU:
			x -= XSPEED;
			y -= YSPEED;
			break;
		case U:
			y -= YSPEED;
			break;
		case RU:
			x += XSPEED;
			y -= YSPEED;
			break;
		case R:
			x += XSPEED;
			break;
		case RD:
			x += XSPEED;
			y += YSPEED;
			break;
		case D:
			y += YSPEED;
			break;
		case LD:
			x -= XSPEED;
			y += YSPEED;
			break;
		}

		if (x < 0 || y < 0 || x > tc.GAME_WIDTH || y > tc.GAME_HEIGHT) {
			live = false;
		}
	}

	public boolean isLive() {
		return live;
	}

	public Rectangle getRect() {
		return new Rectangle(x, y, WIDTH, HEIGHT); //得到子弹的探测方块，Rectangle是java.awt包中专门用于游戏碰撞的类
	}

	//判断子弹是否打到了坦克
	public boolean hitTank(Tank t) {
		//intersects是Rectangle的一个方法；t.isLive()是为了判断坦克是否存活，如果没有则打掉这个坦克后，之后的子弹到达原来这个坦克的位置就会消失
		if (this.live && this.getRect().intersects(t.getRect()) && t.isLive() && this.good != t.isGood()) {
			if (t.isGood()) {
				t.setLife(t.getLife() - 20);
				if (t.getLife() <= 0) {
					t.setLive(false);
				}
			} else {
				t.setLive(false);
			}
			this.live = false;
			Explode e = new Explode(x, y, tc);
			tc.explodes.add(e);
			return true;
		}
		return false;
	}

	public boolean hitTanks(List<Tank> tanks) {
		for (int i = 0; i < tanks.size(); i++) {
			if (hitTank(tanks.get(i))) {
				return true;
			}
		}
		return false;
	}

	public boolean hitWall(Wall w) {
		if(this.live && this.getRect().intersects(w.getRect())) {
			this.live = false;
			return true;
		}
		return false;
	}

}

Explode类：

import java.awt.*;

//爆炸类(爆炸的英文：explode)
public class Explode {

	int x, y;
	private TankClient tc;

	private boolean live = true;

	int[] diameter = {4, 10, 20, 36, 56, 24, 12, 6}; //定义画不同直径的圆表示爆炸(直径的英文:diameter)
	int step = 0; //定义变量代表画爆炸的圆画到第几个了

	public Explode(int x, int y, TankClient tc) {
		this.x = x;
		this.y = y;
		this.tc = tc;
	}

	public void draw(Graphics g) {
		if(!live) {
			tc.explodes.remove(this);
			return;
		}

		if (step == diameter.length) {
			live = false;
			step = 0;
			return;
		}

		Color c = g.getColor();
		g.setColor(Color.ORANGE);
		g.fillOval(x, y, diameter[step], diameter[step]);
		g.setColor(c);

		step ++ ;

	}

}

Wall类：

import java.awt.*;

public class Wall {
	private int x, y, w, h;
	private TankClient tc;

	public Wall(int x, int y, int w, int h, TankClient tc) {
		this.x = x;
		this.y = y;
		this.w = w;
		this.h = h;
		this.tc = tc;
	}

	public void draw(Graphics g) {
		g.fillRect(x, y, w, h);
	}

	public Rectangle getRect() {
		return new Rectangle(x, y, w, h);
	}
}

Blood类：

import java.awt.*;

public class Blood {

	private int x, y, w, h;
	private TankClient tc;

	private boolean live = true;

	private int step = 0;

	int[][] pos = {
					{400,400}, {420,400}, {440,400}, {440,420}, {440,440}, {420,440}, {400,440}, {400,420}
					};

	public Blood(TankClient tc) {
		this.x = pos[0][0];
		this.y = pos[0][1];
		this.w = h = 10;
		this.tc = tc;
	}

	public void draw(Graphics g) {
		if (!live) return;

		Color c = g.getColor();
		g.setColor(Color.MAGENTA);
		g.fillRect(x, y, w, h);
		g.setColor(c);

		move();
	}

	private void move() {
		step ++;

		if(step == pos.length) {
			step = 0;
		}

		x = pos[step][0];
		y = pos[step][1];
	}

	public Rectangle getRect() {
		return new Rectangle(x, y, w, h);
	}

	public boolean isLive() {
		return live;
	}

	public void setLive(boolean live) {
		this.live = live;
	}

}