私は曲リストアプリケーションを構築しています。データ読み込み中にスプラッシュ画面を表示したい。そのためにAsyncTask、ViewSwitcher と組み合わせて、スプラッシュ画面 (ロゴと円のプログレスバーのみ) とメイン画面の間で xml レイアウトを切り替えるように設定しました。問題は、ListView にデータを配置することになると、別のクラスにある BaseAdapter を使用していて、エラーがスローされること"The Constructor LazyAdapter(Home.LoadViewTask, ArrayList<HashMap<String,String>>) is undefined"です。
これは、AsyncTask を持つホーム クラスのソースです。
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.main);
mBtnNaslovnica = (Button) findViewById(R.id.mBtnNaslovnica);
mBtnNaslovnica.setSelected(true);
new LoadViewTask().execute();
}
//To use the AsyncTask, it must be subclassed
public class LoadViewTask extends AsyncTask<Void, Integer, Void>
{
//A TextView object and a ProgressBar object
private TextView tv_progress;
private ProgressBar pb_progressBar;
//Before running code in the separate thread
@Override
protected void onPreExecute()
{
//Initialize the ViewSwitcher object
viewSwitcher = new ViewSwitcher(Home.this);
/* Initialize the loading screen with data from the 'loadingscreen.xml' layout xml file.
* Add the initialized View to the viewSwitcher.*/
viewSwitcher.addView(ViewSwitcher.inflate(Home.this, R.layout.init, null));
//Set ViewSwitcher instance as the current View.
setContentView(viewSwitcher);
}
//The code to be executed in a background thread.
@Override
protected Void doInBackground(Void... params)
{
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);
}
list=(ListView)findViewById(R.id.list);
// 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) {
}
});
return null;
}
//After executing the code in the thread
@Override
protected void onPostExecute(Void result)
{
/* Initialize the application's main interface from the 'main.xml' layout xml file.
* Add the initialized View to the viewSwitcher.*/
viewSwitcher.addView(ViewSwitcher.inflate(Home.this, R.layout.main, null));
//Switch the Views
viewSwitcher.showNext();
}
}
//Override the default back key behavior
@Override
public void onBackPressed()
{
//Emulate the progressDialog.setCancelable(false) behavior
//If the first view is being shown
if(viewSwitcher.getDisplayedChild() == 0)
{
//Do nothing
return;
}
else
{
//Finishes the current Activity
super.onBackPressed();
}
}
そして、これはLazyAdapterクラスのソースです:
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(Home.KEY_TITLE));
artist.setText(song.get(Home.KEY_ARTIST));
duration.setText(song.get(Home.KEY_DURATION));
imageLoader.DisplayImage(song.get(Home.KEY_THUMB_URL), thumb_image);
return vi;
}
`