iPhone tableview: adding new row on top without scrolling up

Question

Hi guys,

I'm wondering how to add rows to the top of tableview without roll the tableview back to the top? Just like the way Twitter did, after reloading, the tableview will be stationary.

I've tried to use the following two without animation

insertRowsAtIndexPaths: withRowAnimation:

scrollToRowAtIndexPath: atScrollPosition:U animated:

but there are visible scroll, any ideas?

Thanks