Asked  7 Months ago    Answers:  5   Viewed   30 times

I'm trying to display a custom progressdialog while loading RSS feed from an HTTP server, I made a hard search, but nothing helped me to do this, the only thing I know is that the solution should use AsyncTask, but I'm confusing about the params to pass to this AsyncTask. Here's my activity :

public class Soirees extends ListActivity {

    private List<Message> messages;
    private TextView tvSorties;
    private MyProgressDialog dialog;

    @Override
    public void onCreate(Bundle icicle) {

        super.onCreate(icicle);
        setContentView(R.layout.sorties);

        tvSorties=(TextView)findViewById(R.id.TVTitle);
        tvSorties.setText("Programme des soirées");

        loadFeed();

    }

    private void loadFeed(){

        try{
            BaseFeedParser parser = new BaseFeedParser();
            messages = parser.parse();
            List<Message> titles = new ArrayList<Message>(messages.size());
            for (Message msg : messages){
                titles.add(msg);
            }
            MessageListAdapter adapter = new MessageListAdapter(this,titles);
            this.setListAdapter(adapter);
            adapter.notifyDataSetChanged();

        } catch (Throwable t){
            Log.e("ImageLoader",t.getMessage(),t);
        }
    }

}

Can you please help me add AsyncTask to this?

 Answers

23

Fixed by moving the view modifiers to onPostExecute so the fixed code is :

public class Soirees extends ListActivity {
    private List<Message> messages;
    private TextView tvSorties;

    //private MyProgressDialog dialog;
    @Override
    public void onCreate(Bundle icicle) {

        super.onCreate(icicle);

        setContentView(R.layout.sorties);

        tvSorties=(TextView)findViewById(R.id.TVTitle);
        tvSorties.setText("Programme des soirées");

        new ProgressTask(Soirees.this).execute();


   }


    private class ProgressTask extends AsyncTask<String, Void, Boolean> {
        private ProgressDialog dialog;
        List<Message> titles;
        private ListActivity activity;
        //private List<Message> messages;
        public ProgressTask(ListActivity activity) {
            this.activity = activity;
            context = activity;
            dialog = new ProgressDialog(context);
        }



        /** progress dialog to show user that the backup is processing. */

        /** application context. */
        private Context context;

        protected void onPreExecute() {
            this.dialog.setMessage("Progress start");
            this.dialog.show();
        }

            @Override
        protected void onPostExecute(final Boolean success) {
                List<Message> titles = new ArrayList<Message>(messages.size());
                for (Message msg : messages){
                    titles.add(msg);
                }
                MessageListAdapter adapter = new MessageListAdapter(activity, titles);
                activity.setListAdapter(adapter);
                adapter.notifyDataSetChanged();

                if (dialog.isShowing()) {
                dialog.dismiss();
            }

            if (success) {
                Toast.makeText(context, "OK", Toast.LENGTH_LONG).show();
            } else {
                Toast.makeText(context, "Error", Toast.LENGTH_LONG).show();
            }
        }

        protected Boolean doInBackground(final String... args) {
            try{    
                BaseFeedParser parser = new BaseFeedParser();
                messages = parser.parse();


                return true;
             } catch (Exception e){
                Log.e("tag", "error", e);
                return false;
             }
          }


    }

}

@Vladimir, thx your code was very helpful.

Tuesday, June 1, 2021
 
Valdas
answered 7 Months ago
91

... I found out it was the .get() method in the accessWebService() method caused this. I tried to implement a progressDialog...

That is right. get() is a blocking call and simply adding a ProgressDialog won't fix it. You need to remove .get() and that will probably fix the issue of your ProgressDialog not showing.

An AsyncTask must be executed on the main Thread so make sure you are doing that.

Another problem you have is Toast.LENGTH_LONG).show(); runs on the UI and you have it in doInBackground() which cannot happen. You need to send the result to onPostExecute() and you can display your Toast there if need. This could also be done in onProgressUpdate().

Saturday, August 21, 2021
 
Freddie
answered 4 Months ago
79

I think the problem is with context of the progress dialog

Try giving the context of the dialog as getParent()

ProgressDialog.show(getParent(), " Loading...", "Please wait...", true, false);

Sunday, August 29, 2021
 
Jon Black
answered 3 Months ago
45

If the ActivityGroup is within a TabActivity you have nested activities with more then two levels. Android doesn't support this at the moment but there is a workaround. You have to pass the parent activity to the dialog.

Create a helper method for this purpose in the activity class:

private Context getDialogContext() {
    Context context;
    if (getParent() != null) context = getParent();
    else context = this;
    return context;
}

Then change the line

private final ProgressDialog dialog = new ProgressDialog(CheckInActivity.this);

to

private final ProgressDialog dialog = new ProgressDialog(getDialogContext());
Wednesday, September 15, 2021
 
u.gen
answered 3 Months ago
87
public MyActivity extends Activity {


  private MyAsyncTask task;

  public onCreate() {
     task = new MyAsyncTask(); // MyAsyncTask has a progress dialog and dismiss it
     // in an overrided cancel() method 
     task.execute();
  }

  private void handleOnBackButton() {
     task.cancel(true);
  }

Then all you need is to call handleOnBackButton() when user presses back or home. You can do it using onKeyDown() method.

Sunday, September 19, 2021
 
Koden
answered 3 Months ago
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