which UITabBarController event to reload a view?

I've got a window with a UITabBarcontroller at the bottom. I have 3 tabs开发者_如何学C, corresponding to their respective views.

Everytime I switch to a view via tapping on the tab, i want it to reload. Which event do I need to tap into? Where would I do this?

thanks!

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How about viewWillAppear: or viewDidAppear: ?