[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] | Reference for unit 'Forms' (#lcl)

# TControlScrollBar.Increment

Number of pixels the display area is scrolled for scroll bar or mouse wheel movements.

## Declaration

Source position: forms.pp line 157

`published property TControlScrollBar.Increment : TScrollBarInc read GetIncrement write SetIncrement default 8;`

## Description

Increment is a TScrollBarInc property which indicates the amount the client area in the associated control is scrolled when the Up or Down navigation arrows on the scroll bar are clicked. It is also used for movements of the mouse wheel on the control. The default value is 8 pixels.

The value in Increment may be automatically recalculated in the UpdateScrollBar method when the Smooth property is enabled and the associated control is a TScrollingWinControl descendant. This is done to ensure that Increment contains 10% of the value for the Page property.

Increment is used in the ScrollHandler method when updating the Position property for scroll bar messages received in the control.

## See also

TControlScrollBar.UpdateScrollBar |  | Updates the state and position for the scroll bar on the associated control.
TControlScrollBar.ControlUpdateScrollBars |  | Forces the associated control to update its scroll bars.
TControlScrollBar.Smooth |  | Enables smooth scrolling, with automatic adjustment of Increment and Page.
TControlScrollBar.Page |  | Number of pixels needed for a page on the associated control.
TControlScrollBar.ScrollHandler |  | Handler for scroll bar movement messages.
TScrollingWinControl |  | Implements a windowed control with scroll bars.
TScrollBarInc |  | The range for scroll bar increments.