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

# TCustomScrollBar.OnChange

Event handler signalled when the value in Position, Min, Max, or PageSize is changed.

## Declaration

Source position: stdctrls.pp line 113

`public property TCustomScrollBar.OnChange : TNotifyEvent read FOnChange write FOnChange;`

## Description

OnChange is a TNotifyEvent property which contains an event handler signalled when scroll information is updated in the control. OnChange is signalled (when assigned) from the Change method, and occurs when the value in Position, Min, Max, or PageSize is changed using SetParams.

Use the OnScroll event handler to respond to events signalled for control messages dispatched to the Scroll method.

## See also

TCustomScrollBar.Position |  | The position of the slider in the scrollbar.
TCustomScrollBar.Min |  | The minimum value for the top or left position depending on orientation.
TCustomScrollBar.Max |  | The maximum value for the bottom or right position depending on orientation.
TCustomScrollBar.PageSize |  | The size of the slider relative to the total scroll range.
TCustomScrollBar.Change |  | Invokes the OnChange event handler for the control.
TCustomScrollBar.SetParams |  | Updates the Min and Max values, the size of the page, and the position in the scrollbar.
TCustomScrollBar.OnScroll |  | Event handler signalled when scrollbar messages are applied.