Allocated memory increases between Activities

Question

My app current has some memory issues, and one of them is this; when I switch between two seemingly simple Activities (each has ~30 TextViews and a few buttons), the Allocated Memory in Android Profile just keeps on increasing. Allocated Memory starts off at about 10MB, and after switching about 20 times it's at 200MB.

I'm calling finish() during onStop of each Activity. Also, onDestroy is getting called each switch.

I've had a thorough look for memory leaks, and don't think it's my code (famous last words?).

Any thoughts on what might be causing it? Is Android Profiler's Allocated Memory reading accurate enough to worry about?

I've no issues running my app on a few physical devices.

EDIT:

I have now tested this with 2 simple Activities. They are identical, apart from button text and where the intent goes, as seen here;

public class ZZZ1Activity extends Activity
{
@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_zzz1);
}

public void SwitchClick(View v)
{
    Intent intent = new Intent(this, ZZZ2Activity.class);
    startActivity(intent);
}
}

and

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ZZZ2Activity">

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:onClick="SwitchClick"
    android:text="SWITCH to 1"
    />

</android.support.constraint.ConstraintLayout>

Switching between these two Activities produces the same result; my Allocated Memory skyrockets. Slower than my real activities, but still alarmingly quick. 100mb+ in 20 switches.

In my experience memory profiler is accurate. Sounds like a classical scenario of a memory leak. — Vasiliy, Apr 06 '18 at 09:40
Why are you calling finish in onStop? Why not after starting new activity? — AbdulAli, Apr 06 '18 at 09:41
@AbdulAli I was just testing. But when you say 'after starting new act', do you mean I should call finish() in the onDestroy? — ausgeorge, Apr 06 '18 at 11:04

score 0 · Answer 1 · answered Apr 06 '18 at 09:42

0

An activities reserved memory may still be held in the memory until the garbage collector removed it. That might be the reason for your issue. Refer to this post for further info.

answered Apr 06 '18 at 09:42

Jujinko

319
3
21

score 0 · Answer 2 · answered Apr 08 '18 at 01:24

I found the issue. I have a Fragment with a UI/View. When an Activity calls onDestroy, it calls the Fragment's onDestroyView. In this I have to clear all references to any UI elements, like this;

@Override
public void onDestroyView()
{
    super.onDestroyView();
    ClearMemory();
}

private void ClearMemory()
{
// clear all references to Views
    btn_newgame = null;
}

Allocated memory increases between Activities

2 Answers2