Android无限循环进度对话框AsyncTask

Question

I got an endless loading and my gridview is not showing. My xml web address is working and everything seems fine. Are there something wrong with my codes? I just modified some codes, im trying to learn Asynctask here. Please help me

CustomizedListView.class

    public class CustomizedListView extends Activity {
        // All static variables
        private ProgressDialog pDialog;
        static final String URL = "http://XXXXXX";
        // XML node keys
        ArrayList<HashMap<String, String>> songsList;
        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";
        static String IMAGE_POSITION;
        GridView grid;
        LazyAdapter adapter;

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.grid_layout);
            //StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();

            //StrictMode.setThreadPolicy(policy); 

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

             new loadGridView().execute();


            grid = (GridView) findViewById(R.id.grid_view);
            grid.setOnItemClickListener(new OnItemClickListener() {

                @Override
                public void onItemClick(AdapterView<?> parent, View view,
                        int position, long id) {
                    String title = ((TextView) view.findViewById(R.id.title)).getText().toString();
                    String artist = ((TextView) view.findViewById(R.id.artist)).getText().toString();
                    String url = ((TextView) view.findViewById(R.id.duration)).getText().toString();
                    // Starting new intent
                    Intent in = new Intent(getApplicationContext(),SingleMenuItemActivity.class);
                    in.getIntExtra(IMAGE_POSITION, position);
                    in.putExtra(KEY_TITLE, title);
                    in.putExtra(KEY_ARTIST, artist);
                    in.putExtra(KEY_THUMB_URL,url);
                    startActivity(in);      

                }
            });
        }

        class loadGridView extends AsyncTask<String, String, String> {

            @Override
            protected void onPreExecute() {
                super.onPreExecute();
                pDialog = new ProgressDialog(
                        CustomizedListView.this);
                pDialog.setMessage("Loading websites ...");
                pDialog.setIndeterminate(false);
                pDialog.setCancelable(false);
                pDialog.show();
            }

            @Override
            protected String doInBackground(String... args) {
                // updating UI from Background Thread


                        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);
                        }


                        return null;

                    }   
@Override
                    protected void onPostExecute(String args) {
                // dismiss the dialog after getting all products
                adapter=new LazyAdapter(CustomizedListView.this, songsList);        
                grid.setAdapter(adapter);
                pDialog.dismiss();
            }


            }

        }

Answer 1

You have to use

adapter=new LazyAdapter(Activityname.this, songsList);

You are not at all using the functionality of doInbackground. Since you are calling runOnuithread again. Remove it.

Move the adapter related call to Ui thread may be in OnpostExecute

Answer 2

Use a context

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

and put Context reference to your AsyncTask Constructor. I suppose best place to fill your adapter in the method

 void onPostExecute(String args) {
// fill your adapter here
        }

instead doInBackground();