Android App中使用SurfaceView制作多线程动画的实例讲解

public class GameView extends SurfaceView implements
    SurfaceHolder.Callback {
 
  //屏幕宽高
  public static int SCREEN_WIDTH;
  public static int SCREEN_HEIGHT;
 
  private Context mContext;
  private SurfaceHolder mHolder;
  //最大帧数 (1000 / 30)
  private static final int DRAW_INTERVAL = 30;
 
  private DrawThread mDrawThread;
  private FrameAnimation []spriteAnimations;
  private Sprite mSprite;
  private int spriteWidth = 0;
  private int spriteHeight = 0;
  private float spriteSpeed = (float)((500 * SCREEN_WIDTH / 480) * 0.001);
  private int row = 4;
  private int col = 4;
 
  public GameSurfaceView(Context context) {
    super(context);
    this.mContext = context;
    mHolder = this.getHolder();
    mHolder.addCallback(this);
    initResources();
 
    mSprite = new Sprite(spriteAnimations,0,0,spriteWidth,spriteHeight,spriteSpeed);
  }
 
  private void initResources() {
    Bitmap[][] spriteImgs = generateBitmapArray(mContext, R.drawable.sprite, row, col);
    spriteAnimations = new FrameAnimation[row];
    for(int i = 0; i < row; i ++) {
      Bitmap []spriteImg = spriteImgs[i];
      FrameAnimation spriteAnimation = new FrameAnimation(spriteImg,new int[]{150,150,150,150},true);
      spriteAnimations[i] = spriteAnimation;
    }
  }
 
  public Bitmap decodeBitmapFromRes(Context context, int resourseId) {
    BitmapFactory.Options opt = new BitmapFactory.Options();
    opt.inPreferredConfig = Bitmap.Config.RGB_565;
    opt.inPurgeable = true;
    opt.inInputShareable = true;
 
    InputStream is = context.getResources().openRawResource(resourseId);
    return BitmapFactory.decodeStream(is, null, opt);
  }
 
  public Bitmap createBitmap(Context context, Bitmap source, int row,
      int col, int rowTotal, int colTotal) {
    Bitmap bitmap = Bitmap.createBitmap(source,
        (col - 1) * source.getWidth() / colTotal,
        (row - 1) * source.getHeight() / rowTotal, source.getWidth()
            / colTotal, source.getHeight() / rowTotal);
    return bitmap;
  }
 
  public Bitmap[][] generateBitmapArray(Context context, int resourseId,
      int row, int col) {
    Bitmap bitmaps[][] = new Bitmap[row][col];
    Bitmap source = decodeBitmapFromRes(context, resourseId);
    this.spriteWidth = source.getWidth() / col;
    this.spriteHeight = source.getHeight() / row;
    for (int i = 1; i <= row; i++) {
      for (int j = 1; j <= col; j++) {
        bitmaps[i - 1][j - 1] = createBitmap(context, source, i, j,
            row, col);
      }
    }
    if (source != null && !source.isRecycled()) {
      source.recycle();
      source = null;
    }
    return bitmaps;
  }
 
  public void surfaceChanged(SurfaceHolder holder, int format, int width,
      int height) {
  }
 
  public void surfaceCreated(SurfaceHolder holder) {
    if(null == mDrawThread) {
      mDrawThread = new DrawThread();
      mDrawThread.start();
    }
  }
 
  public void surfaceDestroyed(SurfaceHolder holder) {
    if(null != mDrawThread) {
      mDrawThread.stopThread();
    }
  }
 
  private class DrawThread extends Thread {
    public boolean isRunning = false;
 
    public DrawThread() {
      isRunning = true;
    }
 
    public void stopThread() {
      isRunning = false;
      boolean workIsNotFinish = true;
      while (workIsNotFinish) {
        try {
          this.join();// 保证run方法执行完毕
        } catch (InterruptedException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
        workIsNotFinish = false;
      }
    }
 
    public void run() {
      long deltaTime = 0;
      long tickTime = 0;
      tickTime = System.currentTimeMillis();
      while (isRunning) {
        Canvas canvas = null;
        try {
          synchronized (mHolder) {
            canvas = mHolder.lockCanvas();
            //设置方向
            mSprite.setDirection();
            //更新精灵位置
            mSprite.updatePosition(deltaTime);
            drawSprite(canvas);
          }
        } catch (Exception e) {
          e.printStackTrace();
        } finally {
          if (null != mHolder) {
            mHolder.unlockCanvasAndPost(canvas);
          }
        }
 
        deltaTime = System.currentTimeMillis() - tickTime;
        if(deltaTime < DRAW_INTERVAL) {
          try {
            Thread.sleep(DRAW_INTERVAL - deltaTime);
          } catch (InterruptedException e) {
            e.printStackTrace();
          }
        }
        tickTime = System.currentTimeMillis();
      }
 
    }
  }
 
  private void drawSprite(Canvas canvas) {
    //清屏操作
    canvas.drawColor(Color.BLACK);
    mSprite.draw(canvas);
  }
 
}

public class Sprite {
 
  public static final int DOWN = 0;
  public static final int LEFT = 1;
  public static final int RIGHT = 2;
  public static final int UP = 3;
 
  public float x;
  public float y;
  public int width;
  public int height;
  //精灵行走速度
  public double speed;
  //精灵当前行走方向
  public int direction;
  //精灵四个方向的动画
  public FrameAnimation[] frameAnimations;
 
  public Sprite(FrameAnimation[] frameAnimations, int positionX,
      int positionY, int width, int height, float speed) {
    this.frameAnimations = frameAnimations;
    this.x = positionX;
    this.y = positionY;
    this.width = width;
    this.height = height;
    this.speed = speed;
  }
 
  public void updatePosition(long deltaTime) {
    switch (direction) {
    case LEFT:
      //让物体的移动速度不受机器性能的影响,每帧精灵需要移动的距离为：移动速度*时间间隔
      this.x = this.x - (float) (this.speed * deltaTime);
      break;
    case DOWN:
      this.y = this.y + (float) (this.speed * deltaTime);
      break;
    case RIGHT:
      this.x = this.x + (float) (this.speed * deltaTime);
      break;
    case UP:
      this.y = this.y - (float) (this.speed * deltaTime);
      break;
    }
  }
 
  /**
   * 根据精灵的当前位置判断是否改变行走方向
   */
  public void setDirection() {
    if (this.x <= 0
        && (this.y + this.height) < GameSurfaceView.SCREEN_HEIGHT) {
      if (this.x < 0)
        this.x = 0;
      this.direction = Sprite.DOWN;
    } else if ((this.y + this.height) >= GameSurfaceView.SCREEN_HEIGHT
        && (this.x + this.width) < GameSurfaceView.SCREEN_WIDTH) {
      if ((this.y + this.height) > GameSurfaceView.SCREEN_HEIGHT)
        this.y = GameSurfaceView.SCREEN_HEIGHT - this.height;
      this.direction = Sprite.RIGHT;
    } else if ((this.x + this.width) >= GameSurfaceView.SCREEN_WIDTH
        && this.y > 0) {
      if ((this.x + this.width) > GameSurfaceView.SCREEN_WIDTH)
        this.x = GameSurfaceView.SCREEN_WIDTH - this.width;
      this.direction = Sprite.UP;
    } else {
      if (this.y < 0)
        this.y = 0;
      this.direction = Sprite.LEFT;
    }
 
  }
 
  public void draw(Canvas canvas) {
    FrameAnimation frameAnimation = frameAnimations[this.direction];
    Bitmap bitmap = frameAnimation.nextFrame();
    if (null != bitmap) {
      canvas.drawBitmap(bitmap, x, y, null);
    }
  }
}

public class FrameAnimation{
  /**动画显示的需要的资源 */
  private Bitmap[] bitmaps;
  /**动画每帧显示的时间 */
  private int[] duration;
  /**动画上一帧显示的时间 */
  protected Long lastBitmapTime;
  /**动画显示的索引值，防止数组越界 */
  protected int step;
  /**动画是否重复播放 */
  protected boolean repeat;
  /**动画重复播放的次数*/
  protected int repeatCount;
 
  /**
   * @param bitmap:显示的图片<br/>
   * @param duration:图片显示的时间<br/>
   * @param repeat:是否重复动画过程<br/>
   */
  public FrameAnimation(Bitmap[] bitmaps, int duration[], boolean repeat) {
    this.bitmaps = bitmaps;
    this.duration = duration;
    this.repeat = repeat;
    lastBitmapTime = null;
    step = 0;
  }
 
  public Bitmap nextFrame() {
    // 判断step是否越界
    if (step >= bitmaps.length) {
      //如果不无限循环
      if( !repeat ) {
        return null;
      } else {
        lastBitmapTime = null;
      }
    }
 
    if (null == lastBitmapTime) {
      // 第一次执行
      lastBitmapTime = System.currentTimeMillis();
      return bitmaps[step = 0];
    }
 
    // 第X次执行
    long nowTime = System.currentTimeMillis();
    if (nowTime - lastBitmapTime <= duration[step]) {
      // 如果还在duration的时间段内,则继续返回当前Bitmap
      // 如果duration的值小于0,则表明永远不失效,一般用于背景
      return bitmaps[step];
    }
    lastBitmapTime = nowTime;
    return bitmaps[step++];// 返回下一Bitmap
  }
 
}

public void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
 
   getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
       WindowManager.LayoutParams.FLAG_FULLSCREEN);
   requestWindowFeature(Window.FEATURE_NO_TITLE);
   getWindow().setFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON,
       WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
 
   DisplayMetrics outMetrics = new DisplayMetrics();
   this.getWindowManager().getDefaultDisplay().getMetrics(outMetrics);
   GameSurfaceView.SCREEN_WIDTH = outMetrics.widthPixels;
   GameSurfaceView.SCREEN_HEIGHT = outMetrics.heightPixels;
   GameSurfaceView gameView = new GameSurfaceView(this);
   setContentView(gameView);
 }