Question

我在ListView上设置ArrayAdapter时面临NullPointerException。

下面提到了代码和例外情况。由于数据是在列表中提供的..我知道它不是NULL。那么为什么这个问题....任何帮助或指针真的很感激！

这是代码： 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;

}
}

例外：

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

你在这里错了。

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

在R.layout.fragment_main

您应该通过ListItem Layout此处

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

ArrayAdapter.createViewFromResource（）上的NullPointerException

1 个答案: