how to get the position number only when I click on a listview item?

//First declare a listview object
protected ListView mListView; 

//Next bind mListView with your listview in the xml (This will be in your onCreate)
mListView = (ListView) findViewById(R.id.list_item);

//Finally, set an onItemClickListener
 mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                // the position of the item clicked will come in as the 3rd parameter of the onItemClick callback
                // which is 'position'. You can use the value to do whatever you want
            }
        });