Fragments with different themes

Question

I'm having a bad struggle in trying to change the theme of my Android Activity in runtime.

This is what I'm trying to archieve: I have an activity (MainActivity) which contains three fragments. Two of those fragments should have a toolbar and a normal status bar, but the third one shouldn't have a toolbar and should have a transparent status bar with content behind it. So, I created two styles: the normal AppTheme with toolbar etc and another one called Fullscreen without those. Now, the theme should change when the fragments are being switched.

I have tried to just change the theme after inflating a new fragment, but that didn't work (obviously).

I also saw this question and a few others and they almost all contain the same answer which doesn't work for me.

I really hope one of you could help!

Thanks

Answer 1

Well you can modify Activity theme and then recreate it to see its effect

class YourActivity{
boolean isThirdFragmentVisible;
...
public void onNavigateToThirdFragment(){
   setTheme(<full screen theme>);
   isThirdFragmentVisible = true;
   recreate();
}

...
public void onCreate(){
   if(isThirdFragmentVisible){
       showThirdFragment();
   }
}
...
}

Answer 2

Any fragment has access to the attached activity. So, fragments can set any activity property, like toolbar and status bar.

Example:

Status bar:

• In onViewCreated callback you can set this mode to not show the status bar:

   getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN) 

• To show the status bar in the other fragments, you can set it in the same way:

   getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE) 

Toolbar:

In the same way, the toolbar can be set by any fragment using setSupportActionBar activity method. More information > https://developer.android.com/training/appbar/setting-up.html#add-toolbar