How to hide the ActionBar from app and show only the flag "back", or to put transparent, but showing only the back button? I want to remove the white part and put the flag white. Thanks!
try -->
getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
yourActionBarid.setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
yourActionBarid.setElevation(0);
Note
Add getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY); before super.onCreate(savedInstanceState);