QToolBar and QAction

[!Ci]

I've got toolbar with some QAction on it. I want make sure that at one time there is only one button pressed(I've set it up as checkable).
I can set pressed button as checked using

actionTriggered ( QAction *)

actionTriggered ( QAction *)

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signal, but how to unset the others?

[jpn]

You can use an exclusive QActionGroup.