android listadapter

protected void onListItemClick(ListView l, View v, int position, long id) {
    // TODO Auto-generated method stub
    super.onListItemClick(l, v, position, id);      
    Cursor c = (Cursor) mAdapter.getItem(position);   开发者_JAVA技巧  
    String a = c.getString(c.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));      
    String b = c.getString(c.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

    if (names != null)
    {
        if(numbers.contains(b))
        {
            names = names.replace(a+";", "");
            numbers = numbers.replace(b+";", "");
            v.setBackgroundResource(R.drawable.background);             
        }
        else{
            names = names + a + ";";
            numbers = numbers + b + ";";
            v.setBackgroundResource(R.drawable.background_sel);
        }
    }
    else
    {
        names = a+";";
        numbers = b+";";
        v.setBackgroundResource(R.drawable.background_sel);
    }   
}

when i select an item random other items background also gets changed although they are not added to the array names and numbers.

i need only the background of the selected item tochange... is there a way to do this without creating my own listadapter ? ?

You should have a look to State List drawables which allow you to define different drawables for each possible states (focus, selected, pressed, etc).

https://developer.android.com/guide/topics/resources/drawable-resource.html#StateList