Android: How to recreate Action bar when fragment changed

Question

I have an activity showing a few fragments. Activity view contains only ViewPager initialized with custom FragmentPagerAdapter. This adapter provide navigation among 3 fragments.

All seems to work fine except Action bar.

I override onCreateOptionsMenu() method in my fragments to create individual Action bar for any fragment:

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
    {
        super.onCreateOptionsMenu(menu, inflater);
        menu.clear();

        //fragment specific menu creation
    }

When I do swipe, new fragment appears, but Action bar stay the same for a few seconds. Probably after a few seconds this method are called and Action bar get changed.

This looks pretty bad when action bar are changed in a while after swipe is finished. How can I recreate action bar immediately, before swipe begin?

roarster roarster · Accepted Answer · 2013-01-23T13:14:15

You can ask android to re-create the actionbar before it automatically does by calling invalidateOptionsMenu();

Do this somewhere close to the point where you change fragments to try and decrease the 'lag' between the fragment and actionbar changing.

Edit

a complete solution may look like this:

class activity extends Activity{

private void switchFragment(){

...do fragment changing stuff

activity.invalidateOptionsMenu();

}

}

class someFragment extends Fragment{

@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater)
{
    super.onCreateOptionsMenu(menu, inflater);
    menu.clear();


    //fragment specific menu creation
}

}

whichever fragment is open during the

activity.invalidateOptionsMenu();

will then call its

 onCreateOptionsMenu

and you can do fragment specific menu creation in there

Android: How to recreate Action bar when fragment changed

4 Answers