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

# TCustomHeaderControl.OnSectionSeparatorDblClick

Event handler signalled when a separator between header sections on the control is double-clicked.

## Declaration

Source position: comctrls.pp line 4111

`published property TCustomHeaderControl.OnSectionSeparatorDblClick : TCustomSectionNotifyEvent read FOnSectionSeparatorDblClick write FOnSectionSeparatorDblClick;`

## Description

OnSectionSeparatorDblClick is a TCustomSectionNotifyEvent property with the event handler signalled when the separator for a header section has been double-clicked. It is signalled (when assigned) from the SectionSeparatorDblClick method. It occurs when the DblClick method handles the mouse event when resize tracking has been enabled by hovering the mouse over the separator for the section.

An application can implement and assign a routine using the signature in TCustomSectionNotifyEvent to respond to the event notification. Arguments passed to the handler include the header control and the header section affected in the event.

Use OnSectionTrack and OnSectionResize to perform actions needed then resize tracking is activated or completed.

## See also

TCustomHeaderControl.Sections |  | Sections - the short segments of the header separated by vertical bars that function as the elementary selection units of the header.
TCustomHeaderControl.DblClick |  | Signals the OnDblClick event handler (when assigned).
TCustomHeaderControl.OnSectionTrack |  | Event handler signalled when drag tracking/resizing is activated for the selected header section on the control.
TCustomHeaderControl.OnSectionResize |  | Event handler signalled when a resize operation for a header section has been completed.
TCustomSectionNotifyEvent |  | TCustomSectionNotifyEvent - generic event notification method for header section.