Using Asynctasks As Separate Public Classes

this question is a continuation of what i have asked orginally here i am trying to find a better way to pass the ArrayList from AsyncTask to the Activity (any activity that calls

Solution 1:

And if you pass the reference of the songsList to the AsynTask?

publicclassSongsManagerextendsAsyncTask<Void, Void, ArrayList<HashMap<String, String>>>    {

    privateArrayList<HashMap<String, String>> songsList; 


    publicSongsManager (ArrayList<HashMap<String, String>> songsList) 
    {         
       this.songsList = songsList;    
    }   


    @OverrideprotectedArrayList<HashMap<String, String>>  doInBackground(Void... params) 
          {
             //populating all the data....HashMap<String, String> map = newHashMap<String, String>();
             //.........
             songsList.add(map);
    }

       return songsList;
    }

    @OverrideprotectedvoidonPostExecute(ArrayList<HashMap<String, String>> result) {
        // TODO Auto-generated method stub//super.onPostExecute(result);

    } 
}

and in the main.java call new SongsManager(songsList).execute();

Solution 2:

Try this

publicclassSongsManagerextendsAsyncTask<Void, Void, ArrayList<HashMap<String, String>>>    {

            publicinterfaceSongsMasterCallback {         
            voidshowSongList(List<HashMap<String, String>> result);     
        } 

        privateSongsMasterCallback  mCallback;      
        publicSongsManager (SongsMasterCallback  callback) 
        {         
            mCallback = callback;    
        }   

        // Constructor//public SongsManager(){ }@OverrideprotectedArrayList<HashMap<String, String>>  doInBackground(Void... params) 
              {
                 ArrayList<HashMap<String, String>> songsList = newArrayList<HashMap<String, String>>();
                 //populating all the data....HashMap<String, String> map = newHashMap<String, String>();
                 //.........return map;
               }

        @OverrideprotectedvoidonPostExecute(ArrayList<HashMap<String, String>> result) {
            // TODO Auto-generated method stub//super.onPostExecute(result);
            songsList.add(result);
            mCallback.showSongList(result); 
        } 

This is happening because you are creating object of songsList in UI thread and adding data in background thread.