android回收AnimationDrawable動畫的每一幀的圖片資源，而釋放內存

回收每一幀的圖片，釋放內存資源

private  void tryRecycleAnimationDrawable(AnimationDrawable animationDrawables) {
		if (animationDrawables != null) {
			animationDrawables.stop();
	        for (int i = 0; i < animationDrawables.getNumberOfFrames(); i++) {
	            Drawable frame = animationDrawables.getFrame(i);
	            if (frame instanceof BitmapDrawable) {
	                ((BitmapDrawable) frame).getBitmap().recycle();
	            }
	            frame.setCallback(null);
	        }
	        animationDrawables.setCallback(null);
	        
	    }
	}

回收完之后可以請求System.gc();回收