Android : custom spinner with last item as a link

I want a Spinner which contains last Item as "Add more items" and when i click on it, then i can add next item. The item i have added should get displayed in spinner list and will have same last item as "Add more items".. I tried using Adapter but how can i keep last element as "Add more items"

spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            if (position == spinner.getItemIdAtPosition(spinner.getCount()))
                // my code
        }

any help??..Thanks ...