TControl.OnMouseWheelHorz property
Event handler signalled for a horizontal movement of the mouse wheel.
Declaration
property OnMouseWheelHorz: TMouseWheelEvent read FOnMouseWheelHorz write FOnMouseWheelHorz;Description
OnMouseWheelHorz is a
TMouseWheelEvent property with
the event handler signalled when a mouse wheel tilt event occurs in the
control. It is signalled (when assigned) from the DoMouseWheelHorz method,
and occurs when the LM_MOUSEHWHEEL message is handled in the WMMouseHWheel
method.
An application can implement and assign a TMouseWheelEvent routine to the event handler to perform actions needed when the event occurs in the control. Other control handlers, created using AddHandler and the chtOnMouseWheelHorz handler type, may be signalled if OnMouseWheelHorz has not been assigned or does not handle the mouse wheel event.
OnMouseWheelLeft or OnMouseWheelRight may be signalled (when assigned) if OnMouseWheelHorz or other control handlers have not been assigned or do not handle the mouse wheel event. The value in the WheelDelta argument determines which handler is used; OnMouseWheelLeft when the delta is a negative number and OnMouseWheelRight when the delta is 0 or a positive number.
OnMouseWheelHorz, and the other horizontal mouse wheel event handlers, require a mouse with a tilting scroll wheel to generate the event notification.
See also
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.