Cancelar ProgressDialog y detener el hilo

Utilice callbacks o AsyncTask

http://developer.android.com/reference/android/os/AsyncTask.html

 final AsyncTask<Void, Void, Void> task = new AsyncTask<Void, Void, Void>() { private ProgressDialog dialog; @Override protected void onPreExecute() { this.dialog = new ProgressDialog(context); this.dialog.setMessage("Loading..."); this.dialog.setCancelable(true); this.dialog.setOnCancelListener(new DialogInterface.OnCancelListener() { @Override public void onCancel(DialogInterface dialog) { // cancel AsyncTask cancel(false); } }); this.dialog.show(); } @Override protected Void doInBackground(Void... params) { // do your stuff return null; } @Override protected void onPostExecute(Void result) { //called on ui thread if (this.dialog != null) { this.dialog.dismiss(); } } @Override protected void onCancelled() { //called on ui thread if (this.dialog != null) { this.dialog.dismiss(); } } }; task.execute(); 

Puede utilizar Asynctask como a continuación

 FetchRSSFeeds fetchRss = new FetchRSSFeeds() fetchRss.execute(); private class FetchRSSFeeds extends AsyncTask<String, Void, Boolean> { private ProgressDialog dialog = new ProgressDialog(HomeActivity.this); /** progress dialog to show user that the backup is processing. */ /** application context. */ protected void onPreExecute() { this.dialog.setMessage(getResources().getString( R.string.Loading_String)); this.dialog.show(); } protected Boolean doInBackground(final String... args) { try { /** * Write your RUN method code here */ if (isCancelled()) { if (dialog.isShowing()) { dialog.dismiss(); } } return true; } catch (Exception e) { Log.e("tag", "error", e); return false; } } @Override protected void onPostExecute(final Boolean success) { } } 

Y cuando quiera cancelar su proceso de fondo haga abajo

 if (fetchRss.getStatus() == AsyncTask.Status.RUNNING) { fetchRss.cancel(true); }