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Object Types: Panels and all control types

Description: When a user scrolls the mouse wheel, LabWindows/CVI generates an EVENT_MOUSE_WHEEL_SCROLL event and sends the event to the callback function associated with the control or panel.

This event is swallowable. Return 1 to swallow EVENT_MOUSE_WHEEL_SCROLL.

Event Data Parameters:

eventData1 = the scroll action (MOUSE_WHEEL_SCROLL_UP, MOUSE_WHEEL_SCROLL_DOWN, MOUSE_WHEEL_PAGE_UP, or MOUSE_WHEEL_PAGE_DOWN).

eventData2 = 0 if eventData1 is MOUSE_WHEEL_PAGE_UP or MOUSE_WHEEL_PAGE_DOWN. If eventData1 is MOUSE_WHEEL_SCROLL_UP or MOUSE_WHEEL_SCROLL_DOWN, eventData2 is the amount to scroll, such as the number of lines the user scrolled.