How to launch a fragment from a fragment while passing a custom object

Question

Building on a previous question and using fragment based approach, the question now is How to launch a fragment from a fragment while passing a custom data object

public class MainActivity extends AppCompatActivity {

    public User user = new User();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        getSupportFragmentManager().beginTransaction()
                .replace(R.id.frame_layout, user)
                .commit();
    }
}

User.java list of users

public class User extends Fragment {

    ListView userList;
    private ArrayList<UserVO> users;

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

        View view =  inflater.inflate(R.layout.user_list, container, false); // Inflate the layout for this fragment
        userList = view.findViewById(R.id.userList);

        users = getUsers(); // ArrayList

        userList.setAdapter(new UserAdapter());
        userList.setOnItemClickListener((adapterView, view1, i, l) -> {
            Log.d("UserList", "onItemClick: " + i);

            // how to launch Form.java Fragment while passing users[i]
        });

        return view;
    }

    class UserAdapter extends BaseAdapter {

        @Override
        public int getCount() {
            return users.size();
        }

        @Override
        public Object getItem(int i) {
            return null;
        }

        @Override
        public long getItemId(int i) {
            return 0;
        }

        @Override
        public View getView(int i, View view, ViewGroup viewGroup) {
            view = LayoutInflater.from(viewGroup.getContext()).inflate(android.R.layout.simple_list_item_1, viewGroup,false);
            ((TextView) view.findViewById(android.R.id.text1)).setText(users.get(i).givenName());
            return view;
        }
    }
}

Form.java which is basically to display user data in a form for update purposes.

public class Form extends Fragment {

    @Nullable
    @Override
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view =  inflater.inflate(R.layout.form, container, false);
        return view;
    }
}

Q1. Within User.java I've a placeholder in the comments, asking for how to instantiate Form.java while passing users[i] (a custom object with fields)

Q2. Please see if there's anything wrong with the approach in MainActivity.java, I've seen the other approach with add method and I'm using replace here, not sure which one is right here.

---

Attempt

I've added following code and not happy from the result, it's overlapping with the list, I want form to have it's own view and place on the stack. Back button should take the user back to the list.

Form form = new Form();

getFragmentManager().beginTransaction()
    .add(R.id.frame_layout, form)
    .commit();

---

Edit 2 For review - based on the answer.

public interface IForm { // 1
   void update(UserObject userObject);
}

public class User extends Fragments implements IForm { // 2
    private Form form = new Form();

    void update(UserObject userObject) {
         // update user list with updated object.
    }

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

    View view =  inflater.inflate(R.layout.user_list, container, false); // Inflate the layout for this fragment
    userList = view.findViewById(R.id.userList);

    users = getUsers(); // ArrayList

    form.delegate = this; // 3

    userList.setOnItemClickListener((adapterView, view1, i, l) -> {
        Log.d("UserList_archive", "onItemClick: " + i);
        form.userData = users[i]; // 4
        getFragmentManager().beginTransaction()
                .replace(R.id.frame_layout, form)
                .addToBackStack(null)
                .commit();
    });

    return view;
}

public class Form {
    public IForm delegate; // 5
    public UserObject userObject; // see 4 - to display data in the form
}

Answer 1

Here you have to use one CallBack/Interface to plug and play with two fragments.

First, write one interface with a method which will do the job, like below:

public interface ItemClickListener extends Parcelable{

   void onItemClick(FormData data);
}

Then initialize this interface in your both Fragments in OnAttach() :

public class UserFragment extends Fragment {

private ItemClickListener onItemClick;

 @Override
public void onAttach(Context context) {
    super.onAttach(context);
    onItemClick= (ItemClickListener) context;
}

Use it inside your onItemClick to pass the value:

 userList.setOnItemClickListener((adapterView, view1, i, l) -> {
        Log.d("UserList", "onItemClick: " + i);

        // how to launch Form.java Fragment while passing users[i]
        onItemClick.onItemClick(adapterView.getItemAtPosition(i);
    });
}

Then implement this interface in your Activity.

public class MainActivity extends AppCompatActivity implements ItemClickListener{

   @override
    public void onItemClick(FormData data){
       //do your stuff here with form data or whatever your object
       //Start Form Fragment and send the data through Bundle
       //https://stackoverflow.com/questions/12739909/send-data-from-activity-to-fragment-in-android 
    }
}