fragments back navigation

Question

I explain the scenario below:

Activity1(fragment1) -> Activity1(fragment2) -> Activity1(fragment3) -> Activity2(fragment4)(OK-button)

if i click on OK button on fragment4 in Activity 2, i should land onto Activity1(fragment2) and upon clicking on back button on fragment 2, it should land onto fragment1.

I tried the following code:

activity?.supportFragmentManager?.popBackStack()

But it doesn't work. Any help or suggestion on how to resolve this issue. You may ask why i'm using lots of fragments here but i really don't have any other options.

Also Have a look at [this question and its answers](https://stackoverflow.com/q/12529499/3559908) — Vall0n, Oct 17 '18 at 14:25
@Vall0n thanks for the response. but as per the link, all the fragments are in one acitvity. but in my case, fragment1,2,3 in one activity and fragment4 is in different activity. — Reddy, Oct 17 '18 at 14:32
Did you try to `activity?.supportFragmentManager?popBackStackImmediate()`? — Vall0n, Oct 17 '18 at 14:44

Karthic Srinivasan · Answer 1 · 2018-10-17T16:16:28.993

When you click on OK button in Activity2(fragment4), just put an entry in sharedPreference before calling Activity1 intent like this:

SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putString(key, "1");
editor.commit();

then call your Activity1:

Intent Activity1 = new Intent(getActivity(), Activity1.class);
startActivity(Activity1);

Now in your Activity1, before setting the contentview, just check the shared preference if it have a variable key with value 1 stored in it. If it contains a value 1, then load fragment2 in the frame layout frm. Like this:

sharedPreferences = getActivity().getSharedPreferences(mypreference, Context.MODE_PRIVATE);
if (sharedPreferences.contains(city)) {
       FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();
       fragmentTransaction.replace(R.id.frm,new fragment2()).addToBackStack(null).commit();
}

When this activity is called normally, shared preference will not have the value 1 in key, so fragment1 will be loaded as your normal flow.

Now, when you move to next fragment from here, just store 0 in key variable in shared preference. This can be done in onDetach() method of the fragment2

Also to go back to fragment1, you can follow this answer for more detailed solution.

fragments back navigation

1 Answers1