Freezing ProgressDialog indicator within AsyncTask with OnItemClickListener

I have the following code in which information about images is loaded from a db and shown in a custom gallery view. The problem is I cannot see a way to put the setting on the OnItemClickListener for the gallery in the background thread of the AsyncTask as it is part of the main UI thread (I think?). When I load the Activity the dialog pops up but freezes and I think it's because I am setting the OnItemClickListener in the UI thread which is taking a lot of work. How can I solve this problem?

private class loadTask extends AsyncTask<String, Integer, String>{

        ProgressDialog dialog = new ProgressDialog(ActivityGallery.this);

        @Override 
        protected void onPreExecute(){
            b = getIntent().getExtras();

            dialog.setMessage("Loading..."); 
            dialog.show();开发者_运维技巧
        }

        @Override
        protected String doInBackground(String... params) {


            Log.v("SC", "ASYNC GETS HERE!!");
            DBHandler handler = new DBHandler(ActivityGallery.this);
            SQLiteDatabase db = handler.getReadableDatabase();

            Cursor c = db.rawQuery("SELECT * FROM images", null);
            if (c.moveToFirst()) {
                do {
                    paths.add(c.getString(1));
                    Log.v("SC", "Cursor: " + c.getString(1)); 
                } while (c.moveToNext());
            } 

            c.close();
            db.close();
            handler.close();
            return null;
        }

        @Override
        protected void onProgressUpdate(Integer... s){

        }

        @Override
        protected void onPostExecute(String result){
            Log.v("SC", "Final Paths: " + paths.toString());

            setContentView(R.layout.gallery);

            gallery = (Gallery) findViewById(R.id.gallery1); 
            gallery.setAdapter(new ImageAdapter(ActivityGallery.this));
            gallery.setOnItemClickListener(new OnItemClickListener() {
                public void onItemClick(AdapterView<?> parent, View v, int position,
                        long id) {
                    selected_image_position = position; 
                    GoToShareActivity();
                }
            });     
            dialog.dismiss();
        }
     }

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I think GoToShareActivity() causes freezing. Check that function in detail.

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What does GoToShareActivity() do?

If it's another resource intensive operation, then it will cause the dialog to freeze up. This is because onPostExecute() runs on the UI thread.

I've a similar program that uses asynctask like you do. I've tried putting my onItemClickListener() in onPostExecute but it doesn't freeze the dialog as i'm not doing any heavy process in it. I understand the part whereby you want to show the gallery to the user after the dialog box dismisses.

ANSWER: You can do the gallery.setOnItemClickListener() in there but, the actual execution of the onClick() should not be in there.

@Override
public void onCreate(Bundle savedInstanceState)
{
    setContentView(R.layout.gallery); //place before your loadTask()
    .
    . //your other implementations
    .
}

private OnItemClickListener galleryOnItemClickListener = new OnItemClickListener()
{
    @Override
    public void onClick(View v)
    {
        selected_image_position = position; 
        GoToShareActivity();
    }
};

private class loadTask extends AsyncTask<String, Integer, String>
{
    .
    .
    .

    protected void onPostExecute(String result)
    {
        Log.v("SC", "Final Paths: " +paths.toString());

        gallery = (Gallery)findViewById(R.id.gallery1);
        gallery.setAdapter(new ImageAdapter(ActivityGallery.this));
        gallery.setOnItemClickListener(galleryOnItemClickListener);

        dialog.dismiss();
    }
}