TUpDown.OnChanging property

Declaration

property OnChanging:;

Description

OnChanging is a TUDChangingEvent property with the event handler signalled prior to setting a new value for the Position property. The handler include a Boolean AllowChange argument which indicates if a change to the Position property is allowed in the control. Setting AllowChange to False in the handler routine prevents a change from being applied to the property value.

OnChanging is signalled (when assigned) from CanChange, and is used to get the return value for the method. It allows the application to accept or reject a change to Position using logic specific to the application.

Use OnChangingEx to implement an event handler which examines the new property value and direction (increase or decrease) for the changed value.

This description is the one of ComCtrls.TCustomUpDown.OnChanging.

See also

• CanChange
• Position
• OnChangingEx
• TUDChangingEvent