How to start and finish progressBar dynamically in android

Question

When I skip second activity class from first activity class, I will start imageprocessing on certain image in second activity and then until new image comes to screen I wnt

Answer 1

Use ProgreaaDialog and AsyncTask. you wil get your soultion Use AsyncTask in doBackInGroundProcess do image processing. and in doPostExecute() exit or cancel the progress dialog

have a look on the sample code. To start AsyncTsk use new ProgressTask().execute(null); from the activity where you want to do image processing.

    private class ProgressTask extends AsyncTask {
        private ProgressDialog dialog;
        List titles;
        private ListActivity activity;
        //private List 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 titles = new ArrayList(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;
             }
          }


    }

}

Have a look here