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dateIncrement

How far into the future/past the calendar navigates when prev/next is executed.

Duration-ish input

Determines how far the calendar will jump when the user presses the prev/next buttons in the headerToolbar or when the prev or next methods are executed.

When using a standard view, it is unnecessary to specify dateIncrement.

When using a Custom View with a specified duration, the duration value will be the default for dateIncrement.