A question related to UI Refresh

I have question related to what is done in SMS application is if i'm in inbox and during the reading of message 开发者_如何学运维if 1 more message opens then the latest message will be updated and then show it on top

how to do it?? can anyone give me code of it.

If you mean the blueish overlay thing, you can implement it via Push Notifications or a UIAlertView.

If you mean the screen with the entire conversation, implement it using a UIScrollView and update when a new message comes in.