Back Button Arrow from Fragment to previous home fragment

Question

I have 5 fragments and every fragment has three dots in top right corner which allows user to go to another child fragment. When user enter that fragment I want to allow them to go back to fragment they were before using back button arrow in right corner. I know if I had activities instead of fragments I could just do it in Android Manifest. I don't know if it is possible to call onClick() method on back arrow button because I created it through code so it does not have an id to select it.

Back Button

@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    setHasOptionsMenu(true);

    ((AppCompatActivity) getActivity()).getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    View rootView = inflater.inflate(R.layout.fragment1, container, false);

    return rootView;
}

Answer 1

To enable access to the home/up button from fragment you need to override and check item ID of android.R.id.home

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {

        case android.R.id.home:

            // Do whatever you want here on home/up button click

            // Replacing a fragment
            FragmentTransaction fragmentTransaction = getActivity().getSupportFragmentManager().beginTransaction();
            Fragment1 fragment1 = new Fragment1();
            fragmentTransaction.addToBackStack("xyz");
            fragmentTransaction.hide(MyCurrentFragment.this);
            fragmentTransaction.add(android.R.id.content, fragment1);
            fragmentTransaction.commit();


            return true;
    }

    return super.onOptionsItemSelected(item);
}