android - why fragment can't hide bottom bar -

why fragment can't hide bottom bar

but activity can hide top , bottom

use following code :

view decorview = getwindow().getdecorview(); int uioptions = view.system_ui_flag_hide_navigation| view.system_ui_flag_fullscreen; decorview.setsystemuivisibility(uioptions);      getactionbar().hide(); 

fragment side didn't work

i try answer 1 still not work when touch fragment area show top , bottom ,let me confused lot

following code: (fragment side)

@override public void oncreate(bundle savedinstancestate)  {    view decorview = getactivity().getwindow().getdecorview();   int uioptions = view.system_ui_flag_hide_navigation|view.system_ui_flag_fullscreen;   decorview.setsystemuivisibility(uioptions);       getactivity().getactionbar().hide(); }   @override public view oncreateview(layoutinflater inflater, viewgroup container,             bundle savedinstancestate)  {    view rootview = inflater.inflate(r.layout.fragment_ge, container, false);    return rootview; } 

chuang, try view.system_ui_flag_immersive_sticky instead of other 2 flags have used. introduced in api 19 per knowledge , require have minimum sdk version same.