android: smoothScrollToPosition() not working correctly

Question

I'm trying to smoothly scroll to last element of a list after adding an element to the arrayadapter associated with the listview. The problem is that it just scrolls to a random position

arrayadapter.add(item);
//DOES NOT WORK CORRECTLY:
listview.smoothScrollToPosition(arrayadapter.getCount()-1);

//WORKS JUST FINE:
listview.setSelection(arrayadapter.getCount()-1);

Answer 1

You probably want to tell the ListView to post the scroll when the UI thread can handle it (which is why yours it not scrolling properly). SmoothScroll needs to do a lot of work, as opposed to just go to a position ignoring velocity/time/etc. (required for an "animation").

Therefore you should do something like:

    getListView().post(new Runnable() {
        @Override
        public void run() {
            getListView().smoothScrollToPosition(pos);
        }
    });