android - ArrayAdapter.createViewFromResource() 上的 NullPointerException

Question

我在 ListView 上设置 ArrayAdapter 时遇到 NullPointerException。

下面提到了代码和异常。由于列表中提供了数据.. 我知道它不是 NULL。 那为什么会出现这个问题......非常感谢任何帮助或指点!

代码如下: MainActivityFragment.java

public class MainActivityFragment extends Fragment {

    public MainActivityFragment() {
}

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

    View view = inflater.inflate(R.layout.fragment_main, container, false);

    List list = new ArrayList<String>();
    list.add("Today - Sunny - 88/63");
    list.add("Tomorrow - Foggy - 88/63");
    list.add("Wednesday - Cloudy - 88/63");
    list.add("Thursday - Rainy - 88/63");
    list.add("Friday - Sunny - 88/63");

    ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getActivity(),
            R.layout.fragment_main,
            R.id.list_item_forecast_textview,
            list);

    ListView listView = (ListView) view.findViewById(R.id.list_view_forecast);
    listView.setAdapter(arrayAdapter);

    return view;

}
}

异常(exception):

java.lang.NullPointerException
at android.widget.ArrayAdapter.createViewFromResource(ArrayAdapter.java:392)
at android.widget.ArrayAdapter.getView(ArrayAdapter.java:362)
at android.widget.AbsListView.obtainView(AbsListView.java:2255)
at android.widget.ListView.makeAndAddView(ListView.java:1790)
at android.widget.ListView.fillDown(ListView.java:691)
at android.widget.ListView.fillFromTop(ListView.java:752)
at android.widget.ListView.layoutChildren(ListView.java:1630)

Answer 1

你错了。

ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getActivity(),
        R.layout.fragment_main,
        R.id.list_item_forecast_textview,
        list);

在 R.layout.fragment_main

你应该在这里传递 ListItem Layout

 ArrayAdapter<String> arrayAdapter = new ArrayAdapter<String>(getActivity(),
        R.layout.yourListItemLayout,
        R.id.list_item_forecast_textview,
        list);