add an extended item at the last.

[luoiori]

how can i add an item at the last.
for example: i search clients, i input "google",
but "google" is not in the datasource. here the item will display "Result Not Found". but i want to add an item afrer "Result Not Found", it writes "+Add google", when i select this item. i will add goole backend.
here is a link pic demo: http://pan.baidu.com/s/1hqTi0bM