Listview 不显示在 Fragment 中

Question

我在 Fragment 中创建了一个 Listview，但是当我执行应用程序时，ListView 没有出现在屏幕上。没有崩溃。我有一个文本视图和一个列表视图。 Textview 显示，但 listview 不显示。

片段代码：

public class PlayerFragment extends Fragment {
private List<Station> myStation = new ArrayList<Station>();
private LayoutInflater mInflater;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    View view =  inflater.inflate(R.layout.fragment_player,
             null);

    populateStationList();
    myStation.add(new Station("station1", "url1", R.drawable.station1, "station1 description"));
    myStation.add(new Station("station2", "url2", R.drawable.station2, "station2 description"));
    myStation.add(new Station("station3", "url3", R.drawable.station3, "station3 description"));

    populateListView();
    ArrayAdapter<Station> adapter = new MyListAdapter();
    ListView list = (ListView) view.findViewById(R.id.stationListView);
    list.setAdapter(adapter);

    registerClickCallback();
    list = (ListView) view.findViewById(R.id.stationListView);
    list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View viewClicked,
                                int position, long id) {
            Station clickedStation = myStation.get(position);
            String message = "You clicked position " + position
                    + "\n" + "Station: " + clickedStation.getStationName();
            Toast.makeText(getActivity(), message, Toast.LENGTH_LONG).show();
        }
    });

    return inflater.inflate(R.layout.fragment_player, container, false);
}

private class MyListAdapter extends ArrayAdapter<Station> {
    public MyListAdapter() {
        super(getActivity(), R.layout.station_list_view, myStation);
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // Make sure we have a view to work with (may have been given null)
        View itemView = convertView;
        if (itemView == null) {
            itemView = mInflater.inflate(R.layout.station_list_view, parent, false);
        }

        // Find the car to work with.
        Station currentStation = myStation.get(position);

        // Fill the view
        ImageView imageView = (ImageView) itemView.findViewById(R.id.item_icon);
        imageView.setImageResource(currentStation.getStationAlbum());

        TextView stationName = (TextView) itemView.findViewById(R.id.item_station_name_text_view);
        stationName.setText(currentStation.getStationName());

        TextView stationURL = (TextView) itemView.findViewById(R.id.item_url_text_view);
        stationURL.setText("" + currentStation.getStationURL());

        TextView stationDescription = (TextView) itemView.findViewById(R.id.item_description_text_view);
        stationDescription.setText(currentStation.getStationDescription());

        return itemView;
        }
    }
}

片段的 XML：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/playerFragment"
    tools:context="com.brandonong.sgpradio.PlayerFragment">
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="heysdadasdasdadasdasd"
        android:id="@+id/textview1"/>
    <ListView
        android:id="@+id/stationListView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/textview1" >
    </ListView>
</RelativeLayout>

Answer 1

问题是，除了布局膨胀inflater.inflate(R.layout.fragment_player, container, false); 之外，所有其他代码都应该放在onViewCreated 中。 试试这个，看看它是否有效！

编辑：

您的 onCreateView：

return inflater.inflate(R.layout.fragment_player, container, false);

OnViewCreated：

 populateStationList();
    myStation.add(new Station("station1", "url1", R.drawable.station1, "station1 description"));
    myStation.add(new Station("station2", "url2", R.drawable.station2, "station2 description"));
    myStation.add(new Station("station3", "url3", R.drawable.station3, "station3 description"));

    populateListView();
    ArrayAdapter<Station> adapter = new MyListAdapter();
    ListView list = (ListView) view.findViewById(R.id.stationListView);
    list.setAdapter(adapter);

    registerClickCallback();
    list = (ListView) view.findViewById(R.id.stationListView);
    list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View viewClicked,
                                int position, long id) {
            Station clickedStation = myStation.get(position);
            String message = "You clicked position " + position
                    + "\n" + "Station: " + clickedStation.getStationName();
            Toast.makeText(getActivity(), message, Toast.LENGTH_LONG).show();
        }
    });

顺便说一句，我真的建议您查看此post 以查看 ViewHolder 模式，这大大提高了您的 ListView 性能！