android - FragmentStatePagerAdapter with dynamic data, IllegalStateException -

i have main fragment has list of items, on clicking item, open detailed view of item in new fragment

using

transaction.replace(r.id.container, feeddetail.newinstance(title, position)).commit(); 

the detailed fragment has fragmentstatepageradapter show sliding list of items. works right, main list of item gets updated in background (asynctask). when sliding items in detailed view,

java.lang.illegalstateexception: application's pageradapter changed adapter's contents without calling pageradapter#notifydatasetchanged! expected adapter item count: 30, found: 40 pager id

i call adapter.notifydatasetchanged() onpostexecute(), still not fix issue. guess issue similar 1 shared here http://translate.google.co.in/translate?hl=en&sl=zh-cn&u=http://blog.csdn.net/hlglinglong/article/details/34845519&prev=search not sure though. have tried different values in getitemposition() of adapter without success. nice hint on issue. pasting detailed fragment code here reference,

public class feeddetail extends fragment {     private viewpager mpager = null;     private pageradapter mpageradapter;     private onfragmentinteractionlistener mlistener;     private fragmentactivity mycontext;     public static string title;     public  static integer pos;     private layoutinflater minflater;     private view  mrootview = null;     viewgroup mviewgroup = null;     public static feeddetail newinstance(string title,  int pos) {         feeddetail fragment = new feeddetail();         bundle args = new bundle();         args.putstring("title", title);         args.putint("pos", pos);         fragment.setarguments(args);         return fragment;     }     public feeddetail() {         // required empty public constructor     }      @override     public void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         if (getarguments() != null) {             title = getarguments().getstring("title");                         pos = getarguments().getint("pos");         }     }       @override     public void ondestroyview()     {         super.ondestroyview();         viewgroup parentviewgroup = (viewgroup) mrootview.getparent();         if( null != parentviewgroup ) {             parentviewgroup.removeallviews();         }         mviewgroup.removeallviews();     }       @override     public view oncreateview(layoutinflater inflater, viewgroup container,                              bundle savedinstancestate) {         // inflate layout fragment         mviewgroup = container;         if (mrootview == null) {             mrootview = (view) inflater.inflate(r.layout.feedpager, null, false);         }         else {             viewgroup parent = (viewgroup) mrootview.getparent();             parent.removeview(mrootview);         }         mpager = (viewpager) mrootview.findviewbyid(r.id.pager);         mpageradapter = new screenslidepageradapter(getchildfragmentmanager());         mpager.setadapter(mpageradapter);         mpager.setcurrentitem(pos);         mrootview.setfocusableintouchmode(true);         mrootview.requestfocus();         return  mrootview;     }         @override     public void onattach(activity activity) {         mycontext=(fragmentactivity) activity;         super.onattach(activity);     }       @override     public void ondetach() {         super.ondetach();          try {             field childfragmentmanager = fragment.class.getdeclaredfield("mchildfragmentmanager");             childfragmentmanager.setaccessible(true);             childfragmentmanager.set(this, null);          } catch (nosuchfieldexception e) {             throw new runtimeexception(e);         } catch (illegalaccessexception e) {             throw new runtimeexception(e);         }     }     public static interface onfragmentinteractionlistener {         public void onfragmentinteraction(uri uri);     }      private class screenslidepageradapter extends fragmentstatepageradapter{         public screenslidepageradapter(fragmentmanager fm) {             super(fm);             setretaininstance(true);         }          @override         public fragment getitem(int position) {             return screenslidepagefragment.newinstance(position);         }          @override         public int getitemposition(object object) {             return 1;         }          @override         public int getcount() {             return navigation.adapter.getcount();         }          @override         public charsequence getpagetitle(int position) {             return navigation.adapter.getfeeds().get(position).title;          }     } }