The fast navigation in RadCalendar
is a built-in feature but we do not have any public API to control that feature. However, I will consider expising API for the next service pack. Unfortunately I cannot provide you with a workaround for this feature so that you could control the items in the navigation menu. The only thing you could do is to it off when the calendar is in read-only mode, but when the calendar is in read-only mode you won't be able to select any date, too.
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