How to make UIBarButtonItem CustomView mutually exclusive?

I added a few button to UIToolbar,开发者_StackOverflow but those buttons can be preesed simultaneousl.

How to make them mutually exclusive just like non-custom view?

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If you want you can set the hidden property to YES for the button you don't want to be pressed until you want it's ready to handle user input (when you just set the same property to NO).