android listview with CheckedTextView

Question

i have a listview using CheckedTextView as its items

when user click one of those items , i want to change the backgroundColor of the item.

i wrote this:

mp3_listView.setOnItemClickListener(new AdapterView.OnItemClickListener() 
        { 
            @Override
            public void onItemClick(AdapterView<?> arg0, View _view, int index , long arg3) 
            { 
                _view.setBackgroundColor(0xCFEDEF);
                }
});

something strange happaned: i click the first item (which index is 0 )

but another item was be change ......not the first one , could anyone tell me why = =a?