I have 4 button to replace fragment in activity [fragment A , fragment B , fragment C , fragment D] and then I replace fragment A to activity and I change value in fragment A after that I replace fragment B to fragment A and replace fragment C to fragment B . But I want to replace fragment A to fragment C . How to save state in fragment A.
Code when I commit fragment
private void beginFragmentTransaction(BaseFragment fragment) {
String tag = fragment.getClass().getName();
currentFragmentTag = tag;
boolean fragmentPopped = getChildFragmentManager().popBackStackImmediate(tag, 0);
if (!fragmentPopped) {
getChildFragmentManager().beginTransaction()
.replace(R.id.container, fragment, tag)
.addToBackStack(tag)
.commit();
}
}
Diagram to replace
fragment A -------> fragment B
fragment B -------> fragment C
fragment C -------> fragment A
PS. I don't want to use back button to back to fragment A , I want to replace fragment A and restore data in the first commit.
Instead of restoring the state during onCreate()
you may choose to implement onRestoreInstanceState()
, which the system calls after the onStart()
method. The system calls onRestoreInstanceState()
only if there is a saved state to restore, so you do not need to check whether the Bundle
is null.
FYI : this is a sample code. Just for your reference.
public class MainFragment extends Fragment {
private String title;
private double rating;
private int year;
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
savedInstanceState.putString(TITLE, "Gladiator");
savedInstanceState.putDouble(RATING, 8.5);
savedInstanceState.putInt(YEAR, 2000);
}
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
title = savedInstanceState.getString(TITLE);
rating = savedInstanceState.getDouble(RATING);
year = savedInstanceState.getInt(YEAR);
}
}
FYI : This really a good thread check this also Once for all, how to correctly save instance state of Fragments in back stack?