Android memory leak between activities

Question

I'm trying to pinpoint this memory leak.

I have two SurfaceViews, A and B. I start A, then navigate to B, then press the back button to go back to A, and then I navigate to B again.

I can see my allocated memory rise each time I do this, and eventually I'll get an out of memory error.

Here is how I navigate to B, from inside the SurfaceView connected to A

        Context context =  this.getContext();
        Intent i =new Intent(context, StartCareer.class);
        i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        context.startActivity(i);

In both views, I have a lot of Bitmaps drawing. In B, I can't find any references to A, and the only reference outside the context that I can think of is a reference to a Global class that I have. I also have some analytics stuff going on in the background. It could be a million different things, I'd imagine

I have the DDMS view on Eclipse up, but I'm not sure what I'm looking at, or how to find the exact object that keeps getting repeated.

I'd accept either a crash-course/tutorial on the DDMS Allocation Tracker, or someone to point out what I'm doing wrong.

Additional information:

I have some bitmaps being drawn on a SurfaceView. Examples of such from B are:

////At class level
Bitmap rightB,leftB;
////In the constructor
rightB = Bitmap.createScaledBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.right), 100,75, true);
////In doDraw
canvas.drawBitmap(rightB, rbX, rbY, null);

And my onDestroys

@Override
public void surfaceDestroyed(SurfaceHolder holder) {


    if (mThread.isAlive()){
        mThread.setMenuRunning(false);
    }
}

So I've run MAT and found one leak, at least. My Thread Keeps getting recreated. Here's what's doing it.

@Override
public void surfaceCreated(SurfaceHolder holder) {
    loading=false;
    if (!mThread.isAlive()){
        mThread = new ViewThread(this);
        mThread.setMenuRunning(true);
        mThread.start();
    }
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {

    if (mThread.isAlive()){ 
        mThread.setMenuRunning(false);
    }
}

Assuming that these methods get called every time the view loses or gains focus, this seems obviously wrong. How can I re-organize this so that it's not?

What does this Global class do? Does it hold any references to any Views, Drawables, Handlers, or anything like that? What about from static variables? There are a number of commonly used objects that keep an entire Activity context in memory. — mkuech, Jan 31 '13 at 07:42
@Siddharth done @mkuech The Global class holds various ints, strings, oh, and a `Resources`, which is set from the constructor of `A` — , Jan 31 '13 at 07:45
See, as soon as you said bitmaps you got a bunch of answers. — Siddharth, Jan 31 '13 at 07:49
Well, I did mention "bitmaps" right under my first block of code — , Jan 31 '13 at 07:50
Now I narrowed down my memory leak, and it is its own question: http://stackoverflow.com/questions/14677913/how-do-i-fix-this-android-memory-leak-involving-threads — , Feb 04 '13 at 20:07

score 4 · Answer 1 · edited Sep 06 '17 at 03:24

4

Call this method in onDestroy() and onstop() of your app.

private void unbindDrawables(View view) {
     Log.d(TAG,"in unbindDrawables");
        if (view.getBackground() != null) {
        view.getBackground().setCallback(null);
        }
        if (view instanceof ViewGroup) {
            for (int i = 0; i < ((ViewGroup) view).getChildCount(); i++) {
            unbindDrawables(((ViewGroup) view).getChildAt(i));
            }
        ((ViewGroup) view).removeAllViews();
        view.setBackgroundResource(0);
        Log.d(TAG,"removed views");
        //finish();
        }
 }

edited Sep 06 '17 at 03:24

seenukarthi

8,241
10
47
68

answered Jan 31 '13 at 07:45

Payal

903
1
9
28

I added this into `B`, but it never reaches the second Log statement – Jan 31 '13 at 07:52
Could you please add some explanation what the code does. – seenukarthi Sep 06 '17 at 03:25

score 3 · Answer 2 · answered Jan 31 '13 at 07:38

3

A few hints:

Recycle bitmaps when done with an activity (onDestroy for example)
Use the application context rather than the activity itself as context whenever possible

answered Jan 31 '13 at 07:38

Vincent Mimoun-Prat

28,208
16
81
124

score 1 · Answer 3 · answered Jan 31 '13 at 07:37

1

Try to recycle() your bitmaps in onDestroy() of your activities.

answered Jan 31 '13 at 07:37

Michał Z.

4,119
1
22
32

I'll try this, but off the top of my head, I don't know how to access members of the view I created – Feb 03 '13 at 20:16
You call recycle() on Bitmap objects you created like: Bitmap rightB,leftB; it would be like rightB.recycle(); – Michał Z. Feb 03 '13 at 20:19
Well, I tried recycling all three of the bitmaps I draw in `B`, but it doesn't seem to help. The memory leak still occurs. The problem must be elsewhere – Feb 03 '13 at 20:32
1

So, I implemented this, and whenever I exit out of my app, and come back in, it crashes since the bitmaps that I'm trying to draw are recycled. Maybe because the bitmap is static. – Feb 09 '13 at 23:21
Static non-trivial members are known to leak context. I would begin the investigation there – Makibo Jul 03 '13 at 23:19

score 0 · Answer 4 · edited May 23 '17 at 11:54

0

What you need to do is explained in detail here. For your specific issue, you need to do this

// resize to desired dimensions
    int height = b.getHeight();
    int width = b.getWidth();
    Log.d(TAG, "1th scale operation dimenions - width: " + width + ",
       height: " + height);

    double y = Math.sqrt(IMAGE_MAX_SIZE
            / (((double) width) / height));
    double x = (y / height) * width;

    Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x, 
       (int) y, true);
    b.recycle();

edited May 23 '17 at 11:54

Community

1
1

answered Jan 31 '13 at 07:51

Siddharth

9,349
16
86
148

I'm having memory leaks. I'm not allocating too much memory toward bitmaps – Feb 03 '13 at 20:46
Regardless of how much memory you are allocating, cleanup is essential. And Bitmaps are known to cause OOM very quickly with relatively small amounts of memory. – Siddharth Feb 04 '13 at 02:36

Android memory leak between activities

4 Answers4