ActionBar 'up' button destroys parent activity, 'back' does not

Question

In the android manifest.xml adding the following attribute for the parent activity tag worked for me.

android:launchMode="singleTop"

Reference : http://developer.android.com/guide/topics/manifest/activity-element.html

Refer the similar question: How can I return to a parent activity correctly?

You can override what the actionbar up button should do like:

public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {

case android.R.id.home:
    onBackPressed();
    return true;
}

return super.onOptionsItemSelected(item);
}

And recreate the back button effect.

when you specify parent activity in manifest then it gets restarted when you click on up Navigation button in action bar.

check this i already answered this question

https://stackoverflow.com/a/32401235/3479012

you need to override up nevigation button in actionbar by accessing it by android.R.id.home in onOptionsItemSelected and do finish top activity.

It looks like your parent activity isn't setup properly in your manifest. Add this inside your ShowInstanceActivity activity tag:

<meta-data android:name="android.support.PARENT_ACTIVITY" android:value=".agenda.ListInstancesActivity" />

So, your final activity tag should look like:

<activity
  android:name=".agenda.ShowInstanceActivity"
  android:label="@string/show_instance_activity_title"
  android:parentActivityName=".agenda.ListInstancesActivity">
  <meta-data android:name="android.support.PARENT_ACTIVITY" android:value=".agenda.ListInstancesActivity" />
</activity>