java - Android recyclerview 在 fragment 中不起作用

Question

我的适配器

public class DepartmentsAdapter extends RecyclerView.Adapter<DepartmentsAdapter.ViewHolder>{

// Store a member variable for the contacts
private List<AppDepartments> mDepartments;
// Store the context for easy access
private Context mContext;


@Override
public DepartmentsAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    Context context = parent.getContext();
    LayoutInflater inflater = LayoutInflater.from(context);

    // Inflate the custom layout
    View contactView = inflater.inflate(R.layout.app_department_item, parent, false);
    // Return a new holder instance
    ViewHolder viewHolder = new ViewHolder(contactView);
    return viewHolder;
}

// Involves populating data into the item through holder
@Override
public void onBindViewHolder(DepartmentsAdapter.ViewHolder holder, int position) {
    AppDepartments appDepartments = mDepartments.get(position);
    // Set item views based on your views and data model
   /* holder.txtViewName.setText(appDepartments.getDeptName());
    holder.txtViewUser.setText(appDepartments.getDeptUser());*/
    holder.txtViewName.setText("HELLO");
    holder.txtViewUser.setText("ITS VICTOR");

}

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

@Override
public int getItemCount() {
    return 0;
}

我的 fragment

public class DiscoverFragment extends Fragment {

public DiscoverFragment() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    View rootView =  inflater.inflate(R.layout.fragment_discover, container, false);
    departmentsAdapter = new DepartmentsAdapter(getActivity(),departList);
    // Lookup the recyclerview in activity layout
    RecyclerView displayDeparts = (RecyclerView) rootView.findViewById(R.id.appDepartments);
    displayDeparts.setAdapter(departmentsAdapter);
    displayDeparts.setLayoutManager(new LinearLayoutManager(getActivity()));
    // Inflate the layout for this fragment
    return rootView;
}

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {

}

@Override
public void onAttach(Context context) {
    super.onAttach(context);
    if (context instanceof OnFragmentInteractionListener) {
        mListener = (OnFragmentInteractionListener) context;
    } else {
        throw new RuntimeException(context.toString()
                + " must implement OnFragmentInteractionListener");
    }
}

}

上面的代码返回一个空白屏幕， TextView 不显示。请帮忙。我已经注释掉了模型，以便我可以使用硬编码文本进行测试。我正在关注这篇文章http://guides.codepath.com/android/Using-the-RecyclerView

Answer 1

@Override
public int getItemCount() {
    return mDepartments.size();
}

(不确定它是否能完全解决您的问题)