Android ListFragment in Tabs not showing on back button return -

i have (relatively) simple drill down application.

it has 1 activity (mainactivity) contains , transitions fragments.

public void gotopartnumbers(){     fragmenttransaction ft = getsupportfragmentmanager().begintransaction();     ft.setcustomanimations(r.anim.slide_in_right, r.anim.slide_out_left, r.anim.slide_in_right, r.anim.slide_out_left);     ft.replace(r.id.container, new identifierfragment()).addtobackstack("partnumber").commit(); } 

identifierfragment tab layout la http://www.androidhive.info/2013/10/android-tab-layout-with-swipeable-views-1/

public class identifierfragment extends fragment implements actionbar.tablistener { private viewpager viewpager; private fragmentstatepageradapter madapter; private actionbar actionbar; private mainactivity mcontext; // tab titles private string[] tabs = { "part numbers", "oem numbers" };  public identifierfragment() {     // required empty public constructor }  @override public view oncreateview(layoutinflater inflater, viewgroup container,                          bundle savedinstancestate) {     // inflate layout fragment     view view = inflater.inflate(r.layout.partnumber_list, container, false);     // initialization     mcontext = (mainactivity) getactivity();     viewpager = (viewpager) view.findviewbyid(r.id.pager);     actionbar = mcontext.getsupportactionbar();      actionbar.setnavigationmode(actionbar.navigation_mode_tabs);     resetadapter( new identifierfragmentadapter(mcontext.getsupportfragmentmanager()) );      (string tab_name : tabs) {         actionbar.addtab(actionbar.newtab().settext(tab_name)                 .settablistener(this));     }     ...i can show rest don't think it's relevant      return view; }  @override public void ondetach(){     super.ondetach();     actionbar.setnavigationmode(actionbar.navigation_mode_standard);     resetadapter(null); }  public void resetadapter(fragmentstatepageradapter adapter){     actionbar.removealltabs();     viewpager.removeallviews();     madapter = adapter;     viewpager.setadapter(madapter); }  ... } 

the 2 child fragments both listfragments cursorloaders. when row selected, identifierfragment replaced using following method:

public void gotogallery(){     fragmenttransaction ft = getsupportfragmentmanager().begintransaction();     galleryhandle = new galleryfragment();     hashmap<string,string> selection = new hashmap<string, string>();     (hashmap<? extends string, ? extends string> c : mcriteria){         selection.putall(c);     }     galleryhandle.setselection(selection);     ft.replace(r.id.container, galleryhandle).addtobackstack("gallery").commit(); } 

when move identifierfragment, works fine. can select row , go detail view. it's when attempt use button detail view viewpager, no listviews!

obviously can supply whatever other code needed. supplied thought relevant.

i'm @ loss, , help. in advance!

isn't because replace current fragment. perhaps if use .add() instead of .replace() when go new gallery

public void gotogallery(){     fragmenttransaction ft = getsupportfragmentmanager().begintransaction();     galleryhandle = new galleryfragment();     hashmap<string,string> selection = new hashmap<string, string>();     (hashmap<? extends string, ? extends string> c : mcriteria){         selection.putall(c);     }     galleryhandle.setselection(selection);     ft.add(r.id.container, galleryhandle).addtobackstack("gallery").commit(); }