FragmentManager popBackStack does not work - Bug?

Question

I am using this code to clear up my backstack up to my main view:

while(mFragmentManager.getBackStackEntryCount() > 1) {
            mFragmentManager.popBackStack(null, 0);
}

I am pretty sure this code was working before, but now the backstack count does not change and no Fragment is being removed, which causes an out of memory exception because the while loop keeps running.

Does anyone know, if there is something wrong with it, or if there is a bug in the latest revision of the SDK-tools. I have no clue what's causing the problem.

look at this [question](http://stackoverflow.com/questions/13086840/actionbar-up-navigation-with-fragments) ; — SohailAziz, Jan 22 '13 at 10:48
the code is inside my onOptionsItemSelected method, and as I said it was working before. I didn't use the function for about 3 weeks or so and now it didn't seem to work anymore — Nickolaus, Jan 22 '13 at 10:59
additionally if you are refering to .popBackStack() without arguments, this has the same effects and doesn't work either — Nickolaus, Jan 22 '13 at 11:09
However, you may try `mFragmentManager.popBackStackImmediate(null, 0);` although you're probably better off calling `mFragmentManager.popBackStackImmediate(mainTag, mFragmentManager.POP_BACK_STACK_INCLUSIVE)` and ditch the loop — Matt, Jan 24 '13 at 18:13

score 11 · Answer 1 · answered Oct 05 '13 at 00:09

11

You are probably looking for popBackStackImmediate(). This immediately executes a back stack pop.

answered Oct 05 '13 at 00:09

christiandeange

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score 7 · Answer 2 · edited Mar 20 '14 at 14:39

7

you can also use .executePendingTransactions(); after popBackStack();

edited Mar 20 '14 at 14:39

elp

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answered Jun 12 '13 at 11:31

Alexander Thiele

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You save my day bro ! Thank you very much ! – anthony Aug 18 '16 at 15:39

score 6 · Accepted Answer · answered Jan 22 '13 at 12:47

6

I certainly would not assume that popBackStack() has an immediate effect, which your loop appears to do.

answered Jan 22 '13 at 12:47

CommonsWare

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That's right. And the two answers below explain how to manage @Nickolaus's issue. – andrea.rinaldi Apr 07 '14 at 10:59

score 3 · Answer 4 · edited Jan 22 '15 at 21:16

What documentation says for popBackStack():

Pop all back stack states up to the one with the given identifier. This function is asynchronous -- it enqueues the request to pop, but the action will not be performed until the application returns to its event loop.

So after mFragmentManager.popBackStack(null, 0); your backstack is not empty until your event is completely processed.

Use popBackStackImmediate() for empty it immediately in the current event itself.

FragmentManager popBackStack does not work - Bug?

4 Answers4