android - 无法应用 ArrayList - Android

Question

LazyAdapter 中的 LazyAdapter (android.app.Activity, ArrayList>) 不能应用于 (com.example.app.CustomizedListView, ArrayList>)

我可以就如何修复此错误或需要更改哪些内容来修复它提供一些意见吗？我不确定您可能需要哪些其他文件，但我不知道哪里出了问题。感谢阅读。

CustomizedListView.class:

public class CustomizedListView extends Fragment {
// All static variables
static final String URL = "http://api.androidhive.info/music/music.xml";
// XML node keys
static final String KEY_SONG = "song"; // parent node
static final String KEY_ID = "id";
static final String KEY_TITLE = "title";
static final String KEY_ARTIST = "artist";
static final String KEY_DURATION = "duration";
static final String KEY_THUMB_URL = "thumb_url";

ListView list;
LazyAdapter adapter;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
    final View v = inflater.inflate(R.layout.main, container, false);
    getActivity().findViewById(R.id.game_list);

}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);


    ArrayList<HashMap<String, String>> songsList = new ArrayList<HashMap<String, String>>();

    XMLParser parser = new XMLParser();
    String xml = parser.getXmlFromUrl(URL); // getting XML from URL
    Document doc = parser.getDomElement(xml); // getting DOM element

    NodeList nl = doc.getElementsByTagName(KEY_SONG);
    // looping through all song nodes <song>
    for (int i = 0; i < nl.getLength(); i++) {
        // creating new HashMap
        HashMap<String, String> map = new HashMap<String, String>();
        Element e = (Element) nl.item(i);
        // adding each child node to HashMap key => value
        map.put(KEY_ID, parser.getValue(e, KEY_ID));
        map.put(KEY_TITLE, parser.getValue(e, KEY_TITLE));
        map.put(KEY_ARTIST, parser.getValue(e, KEY_ARTIST));
        map.put(KEY_DURATION, parser.getValue(e, KEY_DURATION));
        map.put(KEY_THUMB_URL, parser.getValue(e, KEY_THUMB_URL));

        // adding HashList to ArrayList
        songsList.add(map);
    }




    // Getting adapter by passing xml data ArrayList
    adapter=new LazyAdapter(this, songsList);
    list.setAdapter(adapter);


    // Click event for single list row
    list.setOnItemClickListener(new OnItemClickListener() {

        @Override
        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {


        }
    });
}
}

LazyAdapter.class:

public class LazyAdapter extends BaseAdapter {

private Activity activity;
private ArrayList<HashMap<String, String>> data;
private static LayoutInflater inflater=null;
public ImageLoader imageLoader; 

public LazyAdapter(Activity a, ArrayList<HashMap<String, String>> d) {
    activity = a;
    data=d;
    inflater = (LayoutInflater)activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    imageLoader=new ImageLoader(activity.getApplicationContext());
}

public int getCount() {
    return data.size();
}

public Object getItem(int position) {
    return position;
}

public long getItemId(int position) {
    return position;
}

public View getView(int position, View convertView, ViewGroup parent) {
    View vi=convertView;
    if(convertView==null)
        vi = inflater.inflate(R.layout.list_row, null);

    TextView title = (TextView)vi.findViewById(R.id.title); // title
    TextView artist = (TextView)vi.findViewById(R.id.artist); // artist name
    TextView duration = (TextView)vi.findViewById(R.id.duration); // duration
    ImageView thumb_image=(ImageView)vi.findViewById(R.id.list_image); // thumb image

    HashMap<String, String> song = new HashMap<String, String>();
    song = data.get(position);

    // Setting all values in listview
    title.setText(song.get(CustomizedListView.KEY_TITLE));
    artist.setText(song.get(CustomizedListView.KEY_ARTIST));
    duration.setText(song.get(CustomizedListView.KEY_DURATION));
    imageLoader.DisplayImage(song.get(CustomizedListView.KEY_THUMB_URL), thumb_image);
    return vi;
}
}

Answer 1

替换这个

   adapter=new LazyAdapter(this, songsList);

通过

   adapter=new LazyAdapter(getActivity(), songsList);  

您应该使用 getActivity() 获取托管 fragment 的 Activity 的 Activity 上下文。

具体来说， fragment 可以通过getActivity()访问Activity实例。

public final Activity getActivity()

在 API 级别 11 中添加

返回此 fragment 当前关联的 Activity。