java - FragmentManager: popBackStack() and IllegalStateException -

i have activity:

public class myactivity extends appcompatactivity implements fragmentmanager.onbackstackchangedlistener {     ...      @override     public void onbackpressed()     {         if (getfragmentmanager().getbackstackentrycount() > 0) getfragmentmanager().popbackstack();     } } 

simplefragmentmanager:

private static void moveto(basefragment fragment) {     if(fragment != null)     {         fragmentmanager fragmentmanager = _activity.getfragmentmanager();         fragmenttransaction ft = fragmentmanager.begintransaction();          //this           //ft.settransition(fragmenttransaction.transit_fragment_close);         //or            //ft.setcustomanimations(r.animator.enter, r.animator.exit, r.animator.enter, r.animator.exit);         //or         //ft.setcustomanimations(r.animator.enter, r.animator.exit);          basefragment currentfragment = getcurrentfragment();          if(fragment != currentfragment)         {             ft.replace(_containerid, fragment, fragment.gettype());             if (currentfragment != null)             {                 ft.addtobackstack(null);             }             ft.commit();         }     } } 

example fragment:

public class afragment extends basefragment {     @nullable     @override     public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate)     {         if(view == null)         {             view = new alayout(container.getcontext());             view.setlayoutparams(new relativelayout.layoutparams(relativelayout.layoutparams.match_parent, relativelayout.layoutparams.match_parent));         }          return view;     } } 

>>problem<<

the test this, i'm on fragment a, turn on fragment b, change process of animation pieces, click button @ bottom of screen.

from first time can not happen, making these steps several times, application crashes error:

e/androidruntime: fatal exception: main process: com.my.application, pid: 2103 java.lang.illegalstateexception: specified child has parent. must call removeview() on child's parent first. @ android.view.viewgroup.addviewinner(viewgroup.java:4309) @ android.view.viewgroup.addview(viewgroup.java:4145) @ android.view.viewgroup.addview(viewgroup.java:4086) @ android.view.viewgroup.addview(viewgroup.java:4059) @ android.app.fragmentmanagerimpl.movetostate(fragmentmanager.java:985) @ android.app.fragmentmanagerimpl.movetostate(fragmentmanager.java:1148) @ android.app.backstackrecord.run(backstackrecord.java:793) @ android.app.fragmentmanagerimpl.execpendingactions(fragmentmanager.java:1535) @ android.app.fragmentmanagerimpl$1.run(fragmentmanager.java:482) @ android.os.handler.handlecallback(handler.java:739) @ android.os.handler.dispatchmessage(handler.java:95) @ android.os.looper.loop(looper.java:148) @ android.app.activitythread.main(activitythread.java:5417) @ java.lang.reflect.method.invoke(native method) @ com.android.internal.os.zygoteinit$methodandargscaller.run(zygoteinit.java:726) @ com.android.internal.os.zygoteinit.main(zygoteinit.java:616)

this error occurs if use transition animation, here this:

ft.settransition(fragmenttransaction.transit_fragment_close); 

or

ft.setcustomanimations(r.animator.enter, r.animator.exit, r.animator.enter, r.animator.exit); 

or

ft.setcustomanimations(r.animator.enter, r.animator.exit); 

if not use transition animations, there no error!

i have found many of these topics, , found there bug api:

1) https://code.google.com/p/android/issues/detail?id=77670

2) https://code.google.com/p/android/issues/detail?id=89244

my sdk version:

compilesdkversion 23 buildtoolsversion '23.0.1' 

the important thing, in fragment did not delete view this:

public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate) {         ...         viewgroup parent = (viewgroup) view.getparent();         if(parent != null) parent.removeview(view); } 

because want use single view!

tell me please possible correct error?

>>p.s. 1 of variants of solution: disable button while there animation fragments.