Question

I’m loading 100 images from Asset folder to an array object. The pictures are quite small (png ~20k each), and im using this code do to it, and to prevent memory leak & optimized performances:

in a loop:

// create resized bitmap from asset resource
        InputStream istr = assetManager.open(pics[i]);
        Bitmap b = BitmapFactory.decodeStream(istr);
        b = Bitmap.createScaledBitmap(b, 240, 240, true);

where pics[i] is a list of filenames which sits in my Asset folder.

The code works for me, but i still receive from time to time Errors from users (i see it on Developer Console errors):

java.lang.OutOfMemoryError: bitmap size exceeds VM budget
at android.graphics.Bitmap.nativeCreate(Native Method)
at android.graphics.Bitmap.createBitmap(Bitmap.java:468)
at android.graphics.Bitmap.createBitmap(Bitmap.java:435)
at android.graphics.Bitmap.createScaledBitmap(Bitmap.java:340)

Is there anything i can do to improve it? or this is Android’s world, we can never deliever a perfect application?

Answer 1

Of course you can improve something: Don’t load too much pictures into the memory at the same time (or reduce their size). Some devices don’t have much memory available. Your device may have a higher heap limit than some of your customers phones. Therefore it crashes for them when it works for you (see this video for some heap limits [at 4:44]).

You may get the available heap size via ActivityManager.getMemoryClass().

To improve this, test which pictures you need right now (which are displayed) and are which not. Load only the required ones and recycle the bitmaps you don’t need anymore.

Also try using the BitmapFactory.decodeResource() and BitmapFactory.Options.inSampleSize. This allows you to load images at a lower resolution directly without loading them at the full size and then resizing them as you did here.