Question

i am getting friends list from facebook and populating in list view it works fine but now i am trying to add Progress bar till the list view populates but getting exception i have tried searching but not found solution for my issue, here is my code:

public class FriendsProgress extends AsyncTask<Object, Void, Boolean>
    {
        @Override
        protected Boolean doInBackground(Object... Params)
        {
            try
            {
                getFriendList();                                                                    
                friendAdapter = new FriendAdapter(Friends.this, R.layout.activity_friends, friendsList);

                Friends.this.runOnUiThread(new Runnable()
                {
                @Override
                public void run()
                {

                    list.setAdapter(friendAdapter);
                    //list.setOnItemClickListener(EditStaff.this);

                }
                });


            }
            catch (Exception e)
            {
                System.out.println("StaffProgess Exception Caught:"+e.getMessage());
            }
            return Boolean.TRUE;
        }

        @Override
        protected void onPreExecute()
        {

            friendsProgress=new ProgressDialog(Friends.this);
            friendsProgress.setProgressStyle(ProgressDialog.STYLE_SPINNER); 
            friendsProgress.setIndeterminate(true);
            friendsProgress.setMessage("Loading...");       
            friendsProgress.setOwnerActivity(Friends.this);
            friendsProgress.show();

        }

        @Override
        protected void onPostExecute(Boolean Result) 
        {
            friendsProgress.dismiss();
            friendAdapter.notifyDataSetChanged();

        }
    }

here is getFriendsList function implementation:

public void getFriendList(){

        Request request = Request.newMyFriendsRequest(Session.getActiveSession(), new Request.GraphUserListCallback() {

            @Override
            public void onCompleted(List<GraphUser> users, Response response) {
                // TODO Auto-generated method stub

                for(int i=0; i<users.size();i++)
                {
                GraphUser user =    users.get(i);
                Friend objFriend = new Friend();
                objFriend.setFriendID(user.getId());
                objFriend.setFriendName(user.getName());
                Drawable dd =Friends.LoadImageFromWebOperations("http://graph.facebook.com/" + objFriend.getFriendID() + "/picture");
                objFriend.setFriendPic(dd);
                //objFriend.setFriendPic("http://graph.facebook.com/" + objFriend.getFriendID() + "/picture");
                friendsList.add(objFriend);
                //friendAdapter.notifyDataSetChanged();
                Log.d("Friend's Id", objFriend.getFriendID());
                Log.d("Friend's Name", objFriend.getFriendName());
                //Log.d("Friend's Pic", objFriend.getFriendPic());
                Log.d("Friend's List Count", Integer.toString(friendsList.size()));
                }


        }
    });
    Request.executeBatchAsync(request);

Answer 1

You shouldn’t instantiate an Adapter and link it to a ListView inside the doInBackground() method, because it’s running on a worker thread, and no operations connected to Android Views are permitted to be executed on a worker thread. Instead you might want to move this code

friendAdapter = new FriendAdapter(Friends.this, R.layout.activity_friends, friendsList);

            Friends.this.runOnUiThread(new Runnable()
            {
            @Override
            public void run()
            {

                list.setAdapter(friendAdapter);
                //list.setOnItemClickListener(EditStaff.this);

            }
            });

to the onPostExecute() method. This is surely a better designed solution. Hope this helps.