How to hide android fragment in activity to only have one fragment active at the time?

Question

So basically, i have an activity called (Profile Activity) and two fragments connected to it (Profile view and profile edit fragment). Since im completely new with android studio, java language and fragments, im trying to place both fragments into activity but in a way that only profile view fragment is shown. Edit profile fragment needs to be hidden. Im using next part of the code:

getSupportFragmentManager().beginTransaction().add(R.id.profile_fragment, profileViewFragment).commit();
    getSupportFragmentManager().beginTransaction().add(R.id.profile_fragment, profileEditFragment).commit();

I already tried something with "hide" and "show", but with no success. I have imported "android.support.v4.app.FragmentManager;" Thank you.

EDIT:

Profile activity after implementing new code:

public class ProfileActivity extends AppCompatActivity implements ProfileViewFragment.ProfileViewListener {

@Override
protected void onCreate(Bundle savedInstanceState) {
    //ovo ispod je za proslijedivanje iz activita u fragment
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_profile);
    ProfileViewFragment profileViewFragment = new ProfileViewFragment();
    ProfileEditFragment profileEditFragment=new ProfileEditFragment();
    profileViewFragment.setArguments(getIntent().getExtras());
    profileEditFragment.setArguments(getIntent().getExtras());


    //getSupportFragmentManager().beginTransaction().add(R.id.profile_fragment, profileEditFragment).commit();
    getSupportFragmentManager().beginTransaction().add(R.id.profile_fragment, profileViewFragment).commit();
    //getSupportFragmentManager().beginTransaction().replace(R.id.profile_fragment, profileViewFragment).commit();

    //FragmentManager fm=getSupportFragmentManager();
    //fm.beginTransaction().setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out).show(new ProfileViewFragment()).commit();
    //fm.beginTransaction().setCustomAnimations(android.R.anim.fade_in, android.R.anim.fade_out).show(new ProfileEditFragment()).commit();

    //-----------------------------------
}

@Override
public void onOpenProfileEditor() {
    ProfileEditFragment profileEditFragment=new ProfileEditFragment();
    profileEditFragment.setArguments(getIntent().getExtras());

    getSupportFragmentManager().beginTransaction().replace(R.id.profile_fragment, profileEditFragment).commit();
}

@Override
public void onAttachFragment(Fragment fragment) {
    if (fragment instanceof ProfileViewFragment) {
        ProfileViewFragment profileFragment = (ProfileViewFragment) fragment;
        profileFragment.setListener(this::onOpenProfileEditor);
    }
}
}

Profile view fragment with new code:

public class ProfileViewFragment extends Fragment {
private Unbinder unbinder;
//novi kod sa stacka
private ProfileViewListener listener;
//-------------
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {

    FragmentProfileViewBinding viewBinding=DataBindingUtil.inflate(inflater, R.layout.fragment_profile_view, container, false);
    View view=viewBinding.getRoot();
    unbinder = ButterKnife.bind(this, view);

    UserModel user = (UserModel) getArguments().get(ModelEnum.UserModel.name());
    //viewBinding povezuje fragment i xml (proslijeduje user)
    viewBinding.setUser(user);

    //viewBinding.setUserGender(user);
    return view;
}

@Override
public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
}

//    @OnClick(R.id.btn_change_settings)
//    public void changeSettings(){
//getActivity().getSupportFragmentManager().beginTransaction().replace(R.id.profile_fragment, new ProfileEditFragment()).commit();
//    }

@Override
public void onDestroyView() {
    super.onDestroyView();
    unbinder.unbind();
}

//ISPOD JE NOVI KOD SA STACK OVERFLOWA
public interface ProfileViewListener{
    void onProfileEditor();
}

public void setListener(ProfileViewListener listener) {
    this.listener = listener;
}


@OnClick(R.id.btn_change_settings)
public void onEdit(View view){
    if(listener!=null){
        onOpenProfileEditor();
    }
}
}

Answer 1

Instead of

getSupportFragmentManager().beginTransaction().add(R.id.profile_fragment, profileEditFragment).commit();

It must be

getSupportFragmentManager().beginTransaction().replace(R.id.profile_fragment, profileEditFragment).commit();

This will replace your fragment, instead of adding it.

Please, also note that you must call "add" for the first time and use "replace" afterwards.

You may find more about fragments here: https://developer.android.com/training/basics/fragments/fragment-ui

EDIT

For the new issue you have outlined, the solution is to "report" you activity that an event had happened, so it can take action. Here is how to do that.

First, we need an interface (you can add it inside you Profile fragment) and to link the activity to our fragment, if it implements that interface.

public class ProfileViewFragment extends Fragment {
    ...
    ...

    private ProfileViewListener  listener;

    ...
    ...

    @OnClick(R.id.btn_change_settings)
    public onEdit(View view) {
        // If there is anyone listening, report that we need to open editor
        if (listener != null) {
            listener .onOpenProfileEditor();
        }
    }

    public void setListener(ProfileViewListener listener) {
        this.listener = listener;
    }

    // The interface
    public interface ProfileViewListener {
        void onOpenProfileEditor();
    }
}

And in the class, we need to implement the interface and subscribe as a listener.

public class ProfileActivity extends AppCompatActivity implements ProfileViewFragment.ProfileViewListener {

    ...
    ...

    @Override
    public void onOpenProfileEditor() {
        ProfileEditFragment profileEditFragment=new ProfileEditFragment();
        profileEditFragment.setArguments(getIntent().getExtras());

        getSupportFragmentManager()
            .beginTransaction
            .replace(R.id.profile_fragment, profileEditFragment)
            .commit();
    }

    @Override
    public void onAttachFragment(Fragment fragment) {
        if (fragment instanceof ProfileViewFragment) {
            ProfileViewFragment profileFragment = (ProfileViewFragment) fragment;
            profileFragment.setListener(this);
        }
    }
}

You may find more detail on Activity-Fragment communication here - https://developer.android.com/training/basics/fragments/communicating