android - Replacing a fragment in a FrameLayout does not remove the existing fragment from the fragmentManager -

i adding fragment dynamically so:

        fragmentmanager fm = getchildfragmentmanager();         mfragmentmanager.begintransaction().replace(r.id.learn_detail, detailfragment, learn_fragment_threats).commit();         mfragmentmanager.executependingtransactions(); 

i call same code when add different fragment r.id.learn_detail (which framelayout)

the fragment replaced fine, have noticed old fragment still exists in memory.

calling mfragmentmanager.getfragments returns list gets bigger , bigger each time call replace. expected replace destroy old fragment , add new fragment in framelayout. thoughts?

edit - problem was creating new fragment, no matter what. complete method ended looking this:

private learnpagefragment getpagefragment(learnpageitem item) {     learnpagefragment learnpagefragment = (learnpagefragment) mfragmentmanager.findfragmentbytag(learn_fragment_page);      if (learnpagefragment == null) {         learnpagefragment = learnpagefragment.newinstance(item);     } else {         //destroy view , update item data         mfragmentmanager.begintransaction().remove(learnpagefragment).commit();         mfragmentmanager.executependingtransactions();         learnpagefragment.getarguments().putserializable(learnpagefragment.k_content, item);     }     return learnpagefragment; } 

i accepted answer put me on right track. shouldn't trying manually remove fragments fragment manager.

when fragmentmanager removes fragment ui, fragment still being managed fragmentmanager. aside finishing activity, don't know of way tell fragmentmanager "forget" fragment.

the expectation reuse fragments have created rather instantiating new 1 on , over. example, calling fragmenttransaction.add() tag argument, calling fragmentmanager.findfragmentbytag() reference fragment.