Going back to the previous Fragment

Question

I have a program where when one user clicks on a button, it takes them from one fragment to another. The issues is that I want the previous fragment to reappear once the click the back button. Code below:

This is creating the first fragment:

getFragmentManager().beginTransaction().add(R.id.team_fragment_holder, teamFragment).addToBackStack(null).commit();

And this is switching to the second fragment:

setContentView(R.layout.mixed_team_holder);
    FragmentManager fragMan = getFragmentManager();
    FragmentTransaction fragTrans = fragMan.beginTransaction();
    fragTrans.add(R.id.team_1,team1);
    fragTrans.add(R.id.team_2, team2);
    fragTrans.commit();

The problem right now is that when i hit the back button, a blank page appears (i assume is the (R.id.team_fragment_holder). Any idea to make the first fragment reappear along with all the information on it?

Note: all fragments extends listfragment.

Thanks in advance.

score 4 · Answer 1 · answered May 21 '14 at 23:37

4

Your initial fragment transaction should not be added to the backstack and the second one should. The blank page you see when pressing back is the result of removing the teamFragment because it is on the backstack.

getFragmentManager().beginTransaction().add(R.id.team_fragment_holder, teamFragment).commit();

and

FragmentManager fragMan = getFragmentManager();
FragmentTransaction fragTrans = fragMan.beginTransaction();
fragTrans.add(R.id.team_1,team1);
fragTrans.add(R.id.team_2, team2);
fragTrans.addToBackStack(null);
fragTrans.commit();

answered May 21 '14 at 23:37

James McCracken

15,488
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Thanks of the response but it didn't work. After i click the back button, I still get a blank page. Do I have to save everything from the previous fragment before i create the next one and reload it back in after the back button is pressed? – Quinn Wei May 22 '14 at 00:42
Or maybe the blank screen resulted because I set a new layout to display the team1 and team2 fragments? – Quinn Wei May 22 '14 at 00:57
It's probably because you set a new layout. You shouldn't have to re-set your layout like that. It can/should all be handled with Fragments programmatically. – James McCracken May 22 '14 at 03:39

score 1 · Answer 2 · answered May 21 '14 at 23:43

1

You need add the fragment to Back Stack.

FragmentManager fragMan = getFragmentManager();
FragmentTransaction fragTrans = fragMan.beginTransaction();
fragTrans.add(R.id.team_1,team1);
fragTrans.add(R.id.team_2, team2);
fragTrans.addToBackStack(null);//Here add the fragment
fragTrans.commit();

And you need validate the back button.

@Override
public void onBackPressed() {
    if (getSupportFragmentManager().getBackStackEntryCount() == 0) {
        super.onBackPressed();
     } else {
        getSupportFragmentManager().popBackStack();
     }
}

answered May 21 '14 at 23:43

Chefes

1,892
18
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`Activity` already handles popping the fragment backstack for you. There's no need to override onBackPressed(). – James McCracken May 21 '14 at 23:53
Same Problem as the first answer: a blank page is displayed after i press the back button. Just wondering if i need to save everything on the first fragment before calling the second one and reload it afterwards. Thanks! – Quinn Wei May 22 '14 at 00:46

score 1 · Answer 3 · answered Apr 15 '15 at 07:16

public void onClick(View v) {
    switch (v.getId()) {
    case R.id.fragment_button_project_location_ok:

        //getActivity().finish();
        //add back to previous screen
        getFragmentManager().popBackStack();
        break;

    default:
        break;
    }
}

Going back to the previous Fragment

3 Answers3