Sharing integer values among tab bar controllers

In my iOS app I have a main window with a tab bar. Each tab has its own controller, so I have开发者_如何学C multiple .m files. How can I obtain int values from each of these .m files and display them in a different tab (separate .m file)?

Can int values be called globally?

I would like to display all of these different values on one page as an overview.

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Don't use global variables for this. Either save the ints using NSUserDefaults, or send them using NSNotificationCenter.