Fragment Master-Details with saved State

Question

In an activity there is a fragment that contains a list of objects. This fragment should be replaced by another fragment that contains details of a list item. When the detail fragment is active and the back button is pressed then the listfragment should be resumed.

my code:

@Override
    public void onBackPressed() {
            if (detailsFragment.isVisible())
            {
                goToListFragment();
            }
        }
    }

    public void goToListFragment() {
        String backStateName = listFragment.getClass().getName();

        FragmentManager fm = getSupportFragmentManager();
        boolean fragmentPopped = fm.popBackStackImmediate(backStateName, 0);

        if (!fragmentPopped){ //fragment not in back stack, create it.
            FragmentTransaction ft = fm.beginTransaction();
            ft.replace(R.id.main_fragment_container, listFragment);
            ft.addToBackStack(backStateName);
            ft.commit();
        }


    }

    public void goToDetailsFragment(String foodAsJSON) {    
        String backStateName = detailsFragment.getClass().getName();
        getSupportFragmentManager().beginTransaction()
                .replace(R.id.main_fragment_container, detailsFragment)
                .addToBackStack(backStateName)
                .commit();
    }

what I observe:

listfragment: onPause() 
<back pressed in details view>
listfragment: oncreateView()
listfragment: onResume()

So, when the back button is pressed I would expect that only the onResume function is called. Actually that how its described in the fragment lifecycle. But as I have observed the oncreateView() is called too. That causes the fragment to reload completely and that's not the wanted behavior. So, how do I resume the master fragment properly?

What about using `add` instead of `replace` while moving to details fragment ? — Satyen Udeshi, Oct 16 '15 at 09:41
ah, that works kind of. but now my details fragment is not drawn properly. — Anthea, Oct 16 '15 at 09:56
great do you know the reason for why it worked ?? or should i post a answer explaining that ? — Satyen Udeshi, Oct 16 '15 at 09:57
I edited my answer - It seems now my details view is not correctly drawn. I see some elements of my listfragments. It looks like draw() function or so is missing — Anthea, Oct 16 '15 at 10:01
It is because the listfragment is in the view we have just added the detail fragment over list fragment — Satyen Udeshi, Oct 16 '15 at 12:10

Fragment Master-Details with saved State

0 Answers0