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copied!<p>If data for ListAdapter is collected in doInBackground() of AsyncTask, Activity onCreate() does not wait for AsyncTask to complete.</p> <p>So what we have: 1. Activity Start 2. AsyncTask start 3. Activity trying to set ListAdapter - it's empty, because AsyncTask does not completed 4. AsyncTask completed - but ListAdapter filled with empty data</p> <p>My solution: AsyncTask should notify ListAdapter of Activity after data loading completes:</p> <pre><code>Public class MyActivity extends Activity{ @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.myActivity); ExpandableListView listView = (ExpandableListView) findViewById(R.id.expList); //MyArrayList - data source for your list. For example, I use static ArrayList from other class. Replace with your data object. final MyExpandableListAdapter adapter = new MyrExpandableListAdapter(getApplicationContext(), myArrayList); listView.setAdapter(adapter); int taskId=1; // type of task should be executed MyAsyncTask myTask = new MyAsyncTask(taskId); myTask.execute(adapter); @Override protected Dialog onCreateDialog(int id) { ProgressDialog progress = null; progress = new ProgressDialog(this); </code></pre> <p>//Should user work with app while data loading? In my case, no, so setCancelable=false progress.setCancelable(false);</p> <pre><code> if (id==1) { progress.setMessage("Getting locations, please wait..."); } if (id==2) { progress.setMessage("Task type #2 performing..."); } return progress; } // end onCreateDialog class MyAsyncTask extends AsyncTask<Void, Void, Void> { MyExpandableListAdapter adapter; //ExpandableListAdapter you wanna notify about data load completion int taskId; //Type of tasks in your Activity. You have only one, however - getLocations(). MyAsyncTask(int taskId) { //save task ID to use in doInBackground, showDialog and dismissDialog this.taskId=taskId; } @Override protected Void doInBackground(Void... params) { if (taskId==1) { // YOUR LONG-TIME TASK #1 THAT UPDATES DATA SOURCE FOR LIST ADAPTER GOES HERE; } if (taskId==2) { // YOUR LONG-TIME TASK #2 THAT UPDATES DATA SOURCE FOR LIST ADAPTER GOES HERE; // create more task types if needed } //this adapter will be used in onPostExecute() to notify Activity about data changes adapter = (MyExpandableListAdapter) params[0]; return null; } @Override protected void onPreExecute() { //Show dialog for this task type. if need more than one - us switch here and in onCreateDialog, // different dialog types for different tasks etc. showDialog(taskId); } @Override protected void onPostExecute(Void result) { // IMPORTANT! Update data in Activity adapter.notifyDataSetChanged(); dismissDialog(taskId); } } //end of AsyncTask </code></pre> <p>} //end of Activity class</p>

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