回收位圖的後果？

Question

嗨在我的應用程序中，我有一個經常出現的爆炸動畫。當創建爆炸時，我從資源加載3個圖像，然後一旦爆炸動畫結束，我回收這3個圖像。我經常這樣做，並已注意到幀率下降。他們是一個更好的方式來做這個像靜態位圖或什麼的？

Answer 1

我曾經做過一個應用程序，一個炸彈爆炸的簡單畫布。 我使用了由爆炸的每個步驟組成的平鋪位圖，並僅繪製了它的一部分，這經常會爲了創建動畫效果而進行更改。 它更新的步驟之後自動currentTimestamp

所以這是爆炸類：

public class ExplosionAnimated { 

private static final String TAG = ExplosionAnimated.class.getSimpleName(); 

private Bitmap mBitmap; 
private Rect mSourceRect; 
private int mFrameCountX; 
private int mFrameCountY; 
private int mCurrentFrame; 
private long mFrameTicker; 
private int mFramePeriod; 

private int mSpriteWidth; 
private int mSpriteHeight; 

private int mX; 
private int mY; 

private boolean mFinished = false; 

public ExplosionAnimated(Bitmap pBitmap, int pX, int pY, 
     int pFrameCountX, int pFrameCountY, int pFps) { 

    this.mBitmap = pBitmap; 
    this.mX = pX; 
    this.mY = pY; 
    this.mCurrentFrame = 0; 
    this.mFrameCountX = pFrameCountX; 
    this.mFrameCountY = pFrameCountY; 
    this.mSpriteWidth = pBitmap.getWidth()/pFrameCountX; 
    this.mSpriteHeight = pBitmap.getHeight()/pFrameCountY; 
    this.mSourceRect = new Rect(0, 0, this.mSpriteWidth, this.mSpriteHeight); 
    this.mFramePeriod = 1000/pFps; 
    this.mFrameTicker = 0l; 
} 

public void update(long gameTime) { 

    if (gameTime > this.mFrameTicker + this.mFramePeriod) { 
     this.mFrameTicker = gameTime; 

     this.mCurrentFrame++; 
     if (this.mCurrentFrame >= this.mFramePeriod) { 
      this.mCurrentFrame = 0; 
      this.mFinished = true; 
     } 
    } 

    if (!this.mFinished) { 

     this.mSourceRect.left = this.mCurrentFrame * this.mSpriteWidth; 
     this.mSourceRect.right = this.mSourceRect.left + this.mSpriteWidth; 
    } 
} 

public void draw(Canvas canvas) { 

    Rect destRect = new Rect(this.mX, this.mY, 
      this.mX + this.mSpriteWidth, 
      this.mY + this.mSpriteHeight); 
    canvas.drawBitmap(this.mBitmap, this.mSourceRect, destRect, null); 
} 

public boolean isFinished() { 
    return this.mFinished; 
} 
} 

這些都是從一個對象的方法（Bomb.java的爲例）啓動爆炸和繪製：

public void explode(Context pContext, Canvas pCanvas) { 

    this.mState = State.EXPLODING; 
    this.mExplosion = new ExplosionAnimated(this.mExplosionBitmap, 
      (int) this.mX, (int) this.mY, 7, 3, 7); 
} 

public void doDraw(Canvas pCanvas) { 

    if (this.mState == State.EXPLODING) { 

     if (this.mExplosion.isFinished()) { 
      this.mState = State.EXPLODED; 
     } else { 
      this.mExplosion.update(System.currentTimeMillis()); 
      this.mExplosion.draw(pCanvas); 
     } 
    } else { 
     pCanvas.drawBitmap(this.mBombBitmap, this.mX, this.mY, null); 
    } 
} 

我用一個Thread和一個SurfaceView來連續地繪製炸彈（或爆炸），只給出currentTimestamp來更新爆炸。

我希望它能幫助，如果你需要我可以顯示和講解更多的代碼