ProgressDialog not working in external AsyncTask
- by eric
I'm beginning to think that to get a ProgressDialog to work the AsyncTask has to be an inner class within an Activity class. True?
I have an activity the uses a database to manipulate information. If the database is populated all is well. If it is not populated then I need to download information from a website, populate the database, then access the populated database to complete the Views in onCreate.
Problem is without some means to determine when the AsyncTask thread has finished populating the database, I get the following Force Close error message: Sorry! The application has stopped unexpectedly. I click on the Force Close button, the background AsyncTask thread continues to work, the database gets populated, and everything works ok.
I need to get rid of that error message and need some help on how to do this. Here's some psuedo code:
public class ViewStuff extends Activity
{
onCreate
{
if(database is populated)
do_stuff
else
{
FillDB task = null;
if(task == null || task.getStatus().equals(AsyncTask.Status.FINISHED))
{
task = new FillDB(context);
task.execute(null);
}
}
continue with onCreate using information from database to properly display
} // end onCreate
} // end class
In a separate file:
public class FillDB extends AsyncTask<Void, Void, Void>
{
private Context context;
public FillDB (Context c) //pass the context in the constructor
{
context = c;
}
public void filldb ()
{
doInBackground();
}
@Override
protected void onPreExecute()
{
ProgressDialog progressDialog = new ProgressDialog(context);
//crashes with the following line
progressDialog.show(context, "Working..", "Retrieving info");
}
@Override
protected Void doInBackground(Void... params)
{
// TODO Auto-generated method stub
try
etc etc etc
}
}
What am I doing wrong?
