android - pager inside fragment lose data when return from phone Call intent -

i have pager (detail pager) inside gridview whitch (fragment in parent pager) , in other fragment b or c in side parent pager start phone call intent , when intent detail pager lose content . . . pager count of page out draw fragments

notes : structure

pager {fragmenta , fragmentb, fragmentc,fragmentd , .... } fragmenta {gridviewa} gridviewa {detail_pager} 

detail_pager lose content , show white pages

i solve problem using fragmentstatepageradapter and

  @override     public int getitemposition(object object) {         return position_none;} 

and rebuild adapter on page_selected in parent class