RecyclerView 空指针异常

Question

每次我尝试在片段中调用 recyclerView 时都会收到此空点异常。

正如您在下面的代码中看到的那样，我已经声明了我的布局管理器。我尝试在 onViewCreated 和 onCreateView 中声明 recyclerView 和 layoutManager，但仍然出现相同的错误。

这些片段在 viewPager 中，然后每个片段都包含 SwipeRefreshLayout。如果我只使用一个错误未显示，我有 3 个片段都包含 recyclerView。

private RecyclerView post;
private LinearLayoutManager mLayoutManager;
private SwipeRefreshLayout refreshLayout;

public NearByFragment(){

}

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

@Override
public void onActivityCreated(Bundle savedInstanceState) {
    super.onActivityCreated(savedInstanceState);
    post = (RecyclerView) getActivity().findViewById(R.id.lvPost);
    post.setHasFixedSize(true);
    setHasOptionsMenu(true);
    mLayoutManager = new LinearLayoutManager(getActivity());
    mLayoutManager.setOrientation(LinearLayoutManager.VERTICAL);
    post.setLayoutManager(mLayoutManager);
    post.setOnScrollListener(new ScrollListener());
    refreshLayout = (SwipeRefreshLayout) getActivity().findViewById(R.id.swipe_layout);
    refreshLayout.setColorSchemeColors(Color.RED, Color.GREEN, Color.BLUE, Color.YELLOW);
    refreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
        @Override
        public void onRefresh() {
            refreshLayout.setRefreshing(false);
        }
    });
}

Answer 1

如果您的 R.id.lvPost 在 R.layout.fragment_near_by 中。你应该这样做：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_near_by, container, false);
    post = (RecyclerView) view.findViewById(R.id.lvPost);
    return view;
}

RecyclerView 空指针异常

RecyclerView nullpointException

android

android-fragments

android-recyclerview