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androidbitmapheap-memorysurfaceviewddms

Bitmaps and Android Heap

My app uses some bitmaps with a SurfaceView. For bitmaps that a recalled often I stored them as class fields, i.e. when my extension of SurfaceView instance is created I have

bitmap_puppyicon = BitmapFactory.decodeResource(getResources(),R.drawable.puppy);

Where bitmap_puppyicon is a class variable of my extended SurfaceView. WHich means, I think, it is on the heap.

For bitmaps that are used once or twice or so, I created them on the fly in the onDraw() method.

I checked out the heap in DDMS and felt I could afford to store more bitmaps as class variables instead of creating them in onDraw().

To my surprise the heap size went down a few percentage points after doing this. Have I misunderstood something? Why would the heap get smaller with more bitmaps stored?

Solution

  • It use skia under the hood, and heap is not the place where bitmaps live, In the heap you have links to bitmaps only