HThumbDrag Event 442

Applies To: Form, SubForm

Description

If enabled, this event is generated when the user attempts to drag the thumb in a horizontal scrollbar in a Form or SubForm. This event occurs only in a Form or SubForm whose HScroll property is set to ¯1 and is distinct from the Scroll event that is generated by a Scroll object.

The event message reported as the result of ⎕DQ, or supplied as the right argument to your callback function, is a 3-element vector as follows:

[1] Object ref or character vector
[2] Event 'HThumbDrag' or 442
[3] Position numeric

The value of Position is the new (requested) position of the Thumb. Setting the action code of this event to ¯1, or returning a 0 from a callback function attached to it, has no effect.