android - 屏幕旋转后 ListFragment getListView() 返回 null

Question

我在 ListFragment 的 OnActivityCreated() 中调用了 getListView()。它工作正常，但如果我旋转设备屏幕并再次调用 getListView()，它会返回 null。

这是 ListFragment 代码:

public class MyListFragment extends ListFragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.my_list_fragment, container, false);
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        ListView list = getListView();

        if (list != null) {
            //List is not null!
        }
        else {
            //List is null, there is an error.
        }
    }

}

这是布局 xml (my_list_fragment.xml):

<ListView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

Answer 1

我认为你应该在 onViewCreated() 中调用它:

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    ListView list = getListView();

    ...
}