LinearLayoutManager cannot use in Fragment

Question

I have an error on my LinearLayoutManager, when I run this code its says

error: incompatible types: NotificationFragment cannot be converted to Context

Here is my code NotificationFragment.java

public class NotificationFragment extends Fragment {

    private RecyclerView recyclerView;
    private NotificationAdapter adapter;
    private ArrayList<NotificationModel> notificationModelArrayList;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_notification,container,false);

        addData();

        recyclerView = (RecyclerView)   getView().findViewById(R.id.recycler_view);

        adapter = new NotificationAdapter(notificationModelArrayList);

        RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(NotificationFragment.this);

        recyclerView.setLayoutManager(layoutManager);

        recyclerView.setAdapter(adapter);
    }

    void addData(){
        notificationModelArrayList = new ArrayList<>();
        notificationModelArrayList.add(new NotificationModel("Event 1", "1 January 2019", "Surabaya"));
        notificationModelArrayList.add(new NotificationModel("Event 2", "1 January 2019", "Surabaya"));
        notificationModelArrayList.add(new NotificationModel("Event 3", "1 January 2019", "Surabaya"));
        notificationModelArrayList.add(new NotificationModel("Event 4", "1 January 2019", "Surabaya"));
    }

}

The error is on

RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(NotificationFragment.this);

Hope you can help me, thanks.

Answer 1

You can't cast a Fragment to a Context.

Edit this line:

RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(NotificationFragment.this);

to:

    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getContext());

or

    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity());

Remember to check null for getContext() or getActivity() before using it.

For your new question from the comment below, just bring the return statement to the end of function:

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

    addData();

    recyclerView = (RecyclerView)  view.findViewById(R.id.recycler_view);

    adapter = new NotificationAdapter(notificationModelArrayList);
    RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(NotificationFragment.this);
    recyclerView.setLayoutManager(layoutManager);
    recyclerView.setAdapter(adapter);

    return view;
}

Answer 2

Use getActivity() instead of NotificationFragment.this

RecyclerView.LayoutManager layoutManager = new LinearLayoutManager(getActivity());