Android_(游戏)打飞机04：绘画敌机、添加子弹

(游戏)打飞机01：前言　　传送门

(游戏)打飞机02：游戏背景滚动　　传送门

(游戏)打飞机03：控制玩家飞机　　　传送门 

(游戏)打飞机04：绘画敌机、添加子弹　　  传送门

(游戏)打飞机05：处理子弹，击中敌机，添加计分板 　　传送门

(游戏)打飞机06：后续　　传送门

绘画敌机、添加子弹效果

package com.example.administrator.myapplication;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.WindowManager;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;

/**
 * Created by Administrator on 2018/8/9.
 */

public class dafeijiGameView extends SurfaceView implements
        SurfaceHolder.Callback,Runnable,android.view.View.OnTouchListener{

    private Bitmap my;//自己
    private Bitmap baozha;//爆炸
    private Bitmap bg;//背景
    private Bitmap diren;//敌人
    private Bitmap zidan;//子弹
    private Bitmap erjihuancun;//二级缓存
    private WindowManager windowManager;//获得界面长宽高
    private int display_w;  //界面的宽
    private int display_h;  //界面的高
    private ArrayList<GameImage> gameImage = new ArrayList();
    private ArrayList<Zidan> zidans = new ArrayList<Zidan>();

    public dafeijiGameView(Context context) {
        super(context);
        getHolder().addCallback(this);
        //事件注册
        this.setOnTouchListener(this);
    }

    private void init(){
        //加载照片
        my= BitmapFactory.decodeResource(getResources(),R.drawable.my);
        baozha= BitmapFactory.decodeResource(getResources(),R.drawable.baozha);
        bg= BitmapFactory.decodeResource(getResources(),R.drawable.bg);
        diren= BitmapFactory.decodeResource(getResources(),R.drawable.diren);
        zidan= BitmapFactory.decodeResource(getResources(),R.drawable.zidan);

        erjihuancun=Bitmap.createBitmap(display_w,display_h, Bitmap.Config.ARGB_8888);
        gameImage.add(new BeijingImage(bg));    //先加入背景照片
        gameImage.add(new FeijiImage(my));
        gameImage.add(new DijiImage(diren));

    }

    FeijiImage selectfeiji;
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        //手接近屏幕产生的事件
        if(event.getAction()==MotionEvent.ACTION_DOWN){
            for(GameImage game: gameImage){
                if(game instanceof FeijiImage){

                    FeijiImage feiji = (FeijiImage)game;

                    //判断条件为真时选中飞机
                    if(feiji.getX()<event.getX()&&
                            feiji.getY()<event.getY()&&
                            feiji.getX()+feiji.getWidth()>event.getX() &&
                            feiji.getY()+feiji.getHeigth()>event.getY()){
                        selectfeiji=feiji;

                    }else{
                        selectfeiji=null;
                    }
                    break;
                }
            }
        }else if(event.getAction()==MotionEvent.ACTION_MOVE){
            //移动鼠标
            if( selectfeiji!=null){
                selectfeiji.setX((int)event.getX()-selectfeiji.getWidth()/2);
                selectfeiji.setY((int)event.getY()-selectfeiji.getHeigth()/2);
            }

        }else if(event.getAction()==MotionEvent.ACTION_UP){
            //松开鼠标
            selectfeiji=null;
        }

        return true;
    }


    private interface GameImage{
        public Bitmap getBitmap();
        public int getX();
        public int getY();
    }

    private class Zidan implements GameImage{

        Bitmap zidan;
        private FeijiImage feiji;
        private int x;
        private int y;

        public Zidan(FeijiImage feiji,Bitmap zidan){
            this.feiji=feiji;
            this.zidan=zidan;

            x=(feiji.getX()+feiji.getWidth()/2)-25;//居中位置
            y=feiji.getY()-zidan.getHeight();
        }

        public Bitmap getBitmap() {
            y-=19;
            if(y<=-10){
                zidans.remove(this);
            }
            return zidan;
        }

        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }
    }

    private class DijiImage implements GameImage{

        private Bitmap diren = null;

        private List<Bitmap> bitmaps = new ArrayList<Bitmap>();
        private int x;
        private int y;

        public DijiImage(Bitmap diren){
                this.diren=diren;
            bitmaps.add(Bitmap.createBitmap(diren,0,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*1,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*2,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*3,0,diren.getWidth()/4,diren.getHeight()));

           y=-diren.getHeight();
            Random ran = new Random();
            x=ran.nextInt(display_w-(diren.getWidth()/4));

        }

        private int index=0;
        private int num =0;
        @Override
        public Bitmap getBitmap() {
            Bitmap bitmap = bitmaps.get(index);
            //控制切换四个飞机的频率
            if(num == 7){
                index++;
                if(index == bitmaps.size()){
                    index=0;
                }
                num=0;
            }
            y+=3;
            num++;

            if(y>display_h){
                gameImage.remove(this);
            }

            return bitmap;
        }

        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }
    }



    private class FeijiImage implements GameImage{

        private Bitmap my;
        private int x;
        private int y;
        private int width;
        private int heigth;

        private int getWidth(){
            return width;
        }

        private int getHeigth(){
            return heigth;
        }

        private List<Bitmap> bitmaps = new ArrayList<Bitmap>();

        private  FeijiImage(Bitmap my){
            this.my=my;
            bitmaps.add(Bitmap.createBitmap(my,0,0,my.getWidth()/4,my.getHeight()));
            bitmaps.add(Bitmap.createBitmap(my,(my.getWidth()/4),0,my.getWidth()/4,my.getHeight()));
            bitmaps.add(Bitmap.createBitmap(my,(my.getWidth()/4)*2,0,my.getWidth()/4,my.getHeight()));
            bitmaps.add(Bitmap.createBitmap(my,(my.getWidth()/4)*3,0,my.getWidth()/4,my.getHeight()));
            //得到战机的高和宽
            width=my.getWidth()/4;
            heigth=my.getHeight();
            x=(display_w - my.getWidth()/4)/2;
            y=display_h-my.getHeight()-30;
        }

        private int index=0;
        private int num =0;
        @Override
        public Bitmap getBitmap() {
            Bitmap bitmap = bitmaps.get(index);
            //控制切换四个飞机的频率
            if(num == 7){
                index++;
                if(index == bitmaps.size()){
                    index=0;
                }
                num=0;
            }
            num++;
            return bitmap;
        }



        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }

        public void setY(int y){
            this.y=y;
        }

        public void setX(int x){
            this.x=x;
        }

    }

    //负责背景照片的处理
    private class BeijingImage implements GameImage{
        private Bitmap bg;
        private BeijingImage(Bitmap bg){
            this.bg=bg;
            newBitmap = Bitmap.createBitmap(display_w,display_h, Bitmap.Config.ARGB_8888);
        }

        private Bitmap newBitmap = null;
        private int height = 0;

        public Bitmap getBitmap(){
            Paint p = new Paint();
            Canvas canvas = new Canvas(newBitmap);
            canvas.drawBitmap(bg,
                    new Rect(0,0,bg.getWidth(),bg.getHeight()),
                    new Rect(0,height,display_w,display_h+height),p);

            canvas.drawBitmap(bg,
                    new Rect(0,0,bg.getWidth(),bg.getHeight()),
                    new Rect(0,-display_h+height,display_w,height),p);

            height++;
            if(height==display_h){
                height=0;
            }
            return newBitmap;
        }



        public int getX(){
            return 0;
        }

        public int getY(){
            return 0;
        }
    }


    private boolean state = false;
    private SurfaceHolder holder;

    //绘画中心
    public void run() {
        Paint p1 = new Paint();
        int diren_num=0;//
        int zidan_num=0;
        try{
            while(state){
               if(selectfeiji!=null){
                   if(zidan_num==10){
                       zidans.add(new Zidan(selectfeiji,zidan));
                       zidan_num=0;
                   }
                   zidan_num++;
               }

                Canvas newCanvas = new Canvas(erjihuancun);
                for(GameImage image:(List<GameImage>)gameImage.clone()){
                    newCanvas.drawBitmap(image.getBitmap(),image.getX(),image.getY(),p1);
                }

                for(GameImage image:(List<GameImage>)zidans.clone()){
                    newCanvas.drawBitmap(image.getBitmap(),image.getX(),image.getY(),p1);
                }

                if(diren_num==150){
                    diren_num=0;
                    gameImage.add(new DijiImage(diren));
                }
                diren_num++;
                Canvas canvas = holder.lockCanvas();
                canvas.drawBitmap(erjihuancun,0,0,p1);
                holder.unlockCanvasAndPost(canvas);
                Thread.sleep(10);
            }
        }catch(Exception e){
        }
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
    }



    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        state = false;
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        //得到屏幕的宽和高
        display_w=width;
        display_h=height;
        init();
        this.holder=holder;
        state = true;
        new Thread(this).start();
    }

}

package com.example.administrator.myapplication;


import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;


public class MainActivity extends AppCompatActivity{


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //去掉标题
       // requestWindowFeature(Window.FEATURE_NO_TITLE);
          dafeijiGameView view =  new dafeijiGameView(this);

        setContentView(view);
    }


}

实现过程

　　绘制敌机

   private class DijiImage implements GameImage{

        private Bitmap diren = null;

        private List<Bitmap> bitmaps = new ArrayList<Bitmap>();
        private int x;
        private int y;

        public DijiImage(Bitmap diren){
            this.diren=diren;
            bitmaps.add(Bitmap.createBitmap(diren,0,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*1,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*2,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*3,0,diren.getWidth()/4,diren.getHeight()));

            y=-diren.getHeight();
            Random ran = new Random();
            x=ran.nextInt(display_w-(diren.getWidth()/4));

        }

        private int index=0;
        private int num =0;
        @Override
        public Bitmap getBitmap() {
            Bitmap bitmap = bitmaps.get(index);
            //控制切换四个飞机的频率
            if(num == 7){
                index++;
                if(index == bitmaps.size()){
                    index=0;
                }
                num=0;
            }
            y+=3;
            num++;

            if(y>display_h){
                gameImage.remove(this);
            }

            return bitmap;
        }

        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }
    }

　　初始化游戏时候加载敌机类

    private void init(){
        //加载照片
        my= BitmapFactory.decodeResource(getResources(),R.drawable.my);
        baozha= BitmapFactory.decodeResource(getResources(),R.drawable.baozha);
        bg= BitmapFactory.decodeResource(getResources(),R.drawable.bg);
        diren= BitmapFactory.decodeResource(getResources(),R.drawable.diren);
        zidan= BitmapFactory.decodeResource(getResources(),R.drawable.zidan);

        erjihuancun=Bitmap.createBitmap(display_w,display_h, Bitmap.Config.ARGB_8888);
        gameImage.add(new BeijingImage(bg));    //先加入背景照片
        gameImage.add(new FeijiImage(my));
        gameImage.add(new DijiImage(diren));
    }

　　绘制敌机飞行动画

private List<Bitmap> bitmaps = new ArrayList<Bitmap>();

　　将四张敌机加入链表

　　　　　　 bitmaps.add(Bitmap.createBitmap(diren,0,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*1,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*2,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*3,0,diren.getWidth()/4,diren.getHeight()));

 public static Bitmap createBitmap(Bitmap source, int x, int y, int width, int height, Matrix m, boolean filter)
　　从原始位图剪切图像，这是一种高级的方式。可以用Matrix(矩阵)来实现旋转等高级方式截图
　　

　　　　参数说明：　　传送门
　　　　Bitmap source：要从中截图的原始位图
　　　　int x:起始x坐标
　　　　int y：起始y坐标
　　　　int width：要截的图的宽度
　　　　int height：要截的图的宽度
　　　　Bitmap.Config  config：一个枚举类型的配置，可以定义截到的新位图的质量

　　返回值：返回一个剪切好的Bitmap 

 

 

　　绘制飞机飞行动画(不断切换四张图片，看起来像飞机飞)

 

 private int index=0;
        private int num =0;
        @Override
        public Bitmap getBitmap() {
            Bitmap bitmap = bitmaps.get(index);
            //控制切换四个飞机的频率
            if(num == 7){
                index++;
                if(index == bitmaps.size()){
                    index=0;
                }
                num=0;
            }

        //y+=3控制敌机下降速度
        y+=3;        

　　随机位置生成敌机

            y=-diren.getHeight();
            Random ran = new Random();
            x=ran.nextInt(display_w-(diren.getWidth()/4));

　　在游戏绘画中心中添加敌机出现

//绘画中心
    public void run() {
        Paint p1 = new Paint();
        int diren_num=0;//
        try{
            while(true){
                Canvas newCanvas = new Canvas(erjihuancun);
                for(GameImage image:(List<GameImage>)gameImage.clone()){
                    newCanvas.drawBitmap(image.getBitmap(),image.getX(),image.getY(),p1);
                }
                if(diren_num==150){
                    diren_num=0;
                    gameImage.add(new DijiImage(diren));
                }
                diren_num++;
                Canvas canvas = holder.lockCanvas();
                canvas.drawBitmap(erjihuancun,0,0,p1);
                holder.unlockCanvasAndPost(canvas);
                Thread.sleep(10);
            }
        }catch(Exception e){
        }
    }

　　敌机出现频率

                if(diren_num==150){
                    diren_num=0;
                    gameImage.add(new DijiImage(diren));
                }
                diren_num++;

package com.example.administrator.myapplication;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.WindowManager;

import java.util.ArrayList;
import java.util.List;
import java.util.Random;

/**
 * Created by Administrator on 2018/8/9.
 */

public class dafeijiGameView extends SurfaceView implements
        SurfaceHolder.Callback,Runnable,android.view.View.OnTouchListener{

    private Bitmap my;//自己
    private Bitmap baozha;//爆炸
    private Bitmap bg;//背景
    private Bitmap diren;//敌人
    private Bitmap zidan;//子弹
    private Bitmap erjihuancun;//二级缓存
    private WindowManager windowManager;//获得界面长宽高
    private int display_w;  //界面的宽
    private int display_h;  //界面的高
    private ArrayList<GameImage> gameImage = new ArrayList();

    public dafeijiGameView(Context context) {
        super(context);
        getHolder().addCallback(this);
        //事件注册
        this.setOnTouchListener(this);
    }

    private void init(){
        //加载照片
        my= BitmapFactory.decodeResource(getResources(),R.drawable.my);
        baozha= BitmapFactory.decodeResource(getResources(),R.drawable.baozha);
        bg= BitmapFactory.decodeResource(getResources(),R.drawable.bg);
        diren= BitmapFactory.decodeResource(getResources(),R.drawable.diren);
        zidan= BitmapFactory.decodeResource(getResources(),R.drawable.zidan);

        erjihuancun=Bitmap.createBitmap(display_w,display_h, Bitmap.Config.ARGB_8888);
        gameImage.add(new BeijingImage(bg));    //先加入背景照片
        gameImage.add(new FeijiImage(my));
        gameImage.add(new DijiImage(diren));
    }

    FeijiImage selectfeiji;
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        //手接近屏幕产生的事件
        if(event.getAction()==MotionEvent.ACTION_DOWN){
            for(GameImage game: gameImage){
                if(game instanceof FeijiImage){

                    FeijiImage feiji = (FeijiImage)game;

                    //判断条件为真时选中飞机
                    if(feiji.getX()<event.getX()&&
                            feiji.getY()<event.getY()&&
                            feiji.getX()+feiji.getWidth()>event.getX() &&
                            feiji.getY()+feiji.getHeigth()>event.getY()){
                        selectfeiji=feiji;

                    }else{
                        selectfeiji=null;
                    }
                    break;
                }
            }
        }else if(event.getAction()==MotionEvent.ACTION_MOVE){
            //移动鼠标
            if( selectfeiji!=null){
                selectfeiji.setX((int)event.getX()-selectfeiji.getWidth()/2);
                selectfeiji.setY((int)event.getY()-selectfeiji.getHeigth()/2);
            }

        }else if(event.getAction()==MotionEvent.ACTION_UP){
            //松开鼠标
            selectfeiji=null;
        }

        return true;
    }


    private interface GameImage{
        public Bitmap getBitmap();
        public int getX();
        public int getY();
    }

    private class DijiImage implements GameImage{

        private Bitmap diren = null;

        private List<Bitmap> bitmaps = new ArrayList<Bitmap>();
        private int x;
        private int y;

        public DijiImage(Bitmap diren){
                this.diren=diren;
            bitmaps.add(Bitmap.createBitmap(diren,0,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*1,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*2,0,diren.getWidth()/4,diren.getHeight()));
            bitmaps.add(Bitmap.createBitmap(diren,(diren.getWidth()/4)*3,0,diren.getWidth()/4,diren.getHeight()));

           y=-diren.getHeight();
            Random ran = new Random();
            x=ran.nextInt(display_w-(diren.getWidth()/4));

        }

        private int index=0;
        private int num =0;
        @Override
        public Bitmap getBitmap() {
            Bitmap bitmap = bitmaps.get(index);
            //控制切换四个飞机的频率
            if(num == 7){
                index++;
                if(index == bitmaps.size()){
                    index=0;
                }
                num=0;
            }
            y+=3;
            num++;

            if(y>display_h){
                gameImage.remove(this);
            }

            return bitmap;
        }

        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }
    }



    private class FeijiImage implements GameImage{

        private Bitmap my;
        private int x;
        private int y;
        private int width;
        private int heigth;

        private int getWidth(){
            return width;
        }

        private int getHeigth(){
            return heigth;
        }

        private List<Bitmap> bitmaps = new ArrayList<Bitmap>();

        private  FeijiImage(Bitmap my){
            this.my=my;
            bitmaps.add(Bitmap.createBitmap(my,0,0,my.getWidth()/4,my.getHeight()));
            bitmaps.add(Bitmap.createBitmap(my,(my.getWidth()/4),0,my.getWidth()/4,my.getHeight()));
            bitmaps.add(Bitmap.createBitmap(my,(my.getWidth()/4)*2,0,my.getWidth()/4,my.getHeight()));
            bitmaps.add(Bitmap.createBitmap(my,(my.getWidth()/4)*3,0,my.getWidth()/4,my.getHeight()));
            //得到战机的高和宽
            width=my.getWidth()/4;
            heigth=my.getHeight();
            x=(display_w - my.getWidth()/4)/2;
            y=display_h-my.getHeight()-30;
        }

        private int index=0;
        private int num =0;
        @Override
        public Bitmap getBitmap() {
            Bitmap bitmap = bitmaps.get(index);
            //控制切换四个飞机的频率
            if(num == 7){
                index++;
                if(index == bitmaps.size()){
                    index=0;
                }
                num=0;
            }
            num++;
            return bitmap;
        }



        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }

        public void setY(int y){
            this.y=y;
        }

        public void setX(int x){
            this.x=x;
        }

    }

    //负责背景照片的处理
    private class BeijingImage implements GameImage{
        private Bitmap bg;
        private BeijingImage(Bitmap bg){
            this.bg=bg;
            newBitmap = Bitmap.createBitmap(display_w,display_h, Bitmap.Config.ARGB_8888);
        }

        private Bitmap newBitmap = null;
        private int height = 0;

        public Bitmap getBitmap(){
            Paint p = new Paint();
            Canvas canvas = new Canvas(newBitmap);
            canvas.drawBitmap(bg,
                    new Rect(0,0,bg.getWidth(),bg.getHeight()),
                    new Rect(0,height,display_w,display_h+height),p);

            canvas.drawBitmap(bg,
                    new Rect(0,0,bg.getWidth(),bg.getHeight()),
                    new Rect(0,-display_h+height,display_w,height),p);

            height++;
            if(height==display_h){
                height=0;
            }
            return newBitmap;
        }



        public int getX(){
            return 0;
        }

        public int getY(){
            return 0;
        }
    }


    private boolean state = false;
    private SurfaceHolder holder;

    //绘画中心
    public void run() {
        Paint p1 = new Paint();
        int diren_num=0;//
        try{
            while(true){
                Canvas newCanvas = new Canvas(erjihuancun);
                for(GameImage image:(List<GameImage>)gameImage.clone()){
                    newCanvas.drawBitmap(image.getBitmap(),image.getX(),image.getY(),p1);
                }
                if(diren_num==150){
                    diren_num=0;
                    gameImage.add(new DijiImage(diren));
                }
                diren_num++;
                Canvas canvas = holder.lockCanvas();
                canvas.drawBitmap(erjihuancun,0,0,p1);
                holder.unlockCanvasAndPost(canvas);
                Thread.sleep(10);
            }
        }catch(Exception e){
        }
    }

    @Override
    public void surfaceCreated(SurfaceHolder holder) {
    }



    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        state = false;
    }

    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
        //得到屏幕的宽和高
        display_w=width;
        display_h=height;
        init();
        this.holder=holder;
        state = true;
        new Thread(this).start();
    }

}

游戏中添加子弹

 private class Zidan implements GameImage{

        Bitmap zidan;
        private FeijiImage feiji;
        private int x;
        private int y;

        public Zidan(FeijiImage feiji,Bitmap zidan){
            this.feiji=feiji;
            this.zidan=zidan;

            x=(feiji.getX()+feiji.getWidth()/2)-25;//居中位置
            y=feiji.getY()-zidan.getHeight();
        }

        public Bitmap getBitmap() {
            y-=19;
            if(y<=-10){
                zidans.remove(this);
            }
            return zidan;
        }

        @Override
        public int getX() {
            return x;
        }

        @Override
        public int getY() {
            return y;
        }
    }

　　判断子弹出现飞机位置

        public Zidan(FeijiImage feiji,Bitmap zidan){
            this.feiji=feiji;
            this.zidan=zidan;

            x=(feiji.getX()+feiji.getWidth()/2)-25;//居中位置
            y=feiji.getY()-zidan.getHeight();
        }

　　(-25是自己微调)

　　子弹超出边界的时候释放子弹内存，减少手机开销

        public Bitmap getBitmap() {
            y-=19;
            if(y<=-10){
                zidans.remove(this);
            }
            return zidan;
        }

　　不断的出现新的子弹

                if(selectfeiji!=null){
                    if(zidan_num==10){
                        zidans.add(new Zidan(selectfeiji,zidan));
                        zidan_num=0;
                    }
                    zidan_num++;
                }

　　便利所有的子弹

                for(GameImage image:(List<GameImage>)zidans.clone()){
                    newCanvas.drawBitmap(image.getBitmap(),image.getX(),image.getY(),p1);
                }