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

TCustomHeaderControl.OnSectionDrag

Event handler signalled to determine whether a header section can be dragged and dropped at a new position on the control.

Declaration

Source position: comctrls.pp line 4099

published property TCustomHeaderControl.OnSectionDrag : TSectionDragEvent
  read FOnSectionDrag
  write FOnSectionDrag;

Description

OnSectionDrag is a TSectionDragEvent property with the event handler signalled when a drag and drop operation for a section header is requested.

Arguments passed to the TSectionDragEvent routine include the Sender object (TCustomHeaderControl) for the event notification, and THeaderSection instances representing the dragged section and the section that is the target for the drag request. The AllowDrag variable parameter is used to indicate whether the drag and drop operation using the specified source and destination is allowed. Setting AllowDrag to False in the handler prevents the drag and drop operation for the specified sections.

OnSectionDrag is signalled (when assigned) from the SectionDrag method, and occurs if DragReorder has been enabled for the control.

See also

TCustomHeaderControl.DragReorder

  

Enables or disables reordering of header sections on the control using drag and drop.

TCustomHeaderControl.Sections

  

Sections - the short segments of the header separated by vertical bars that function as the elementary selection units of the header.

TCustomHeaderControl.SectionDrag

  

Signals the OnSectionDrag event handler (when assigned and enabled).

TSectionDragEvent

  

TSectionDragEvent - generic event handling method for dragging a header section.


Version 4.0 Generated 2025-05-03 Home