getting the data of selected tabbed page only on the click of update button

hi,
i have a dynamically created tabbed page(by providing a observable collection as items source ). now user have the option to modifying any of the page data click on the update on that page. and i want to update the data for that page only.
i think i something to do with the selected tab but i am not getting to keep track of the selected tab among the almost identical tabs.