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

# TCustomTabControl.Change

Performs actions to show or hide pages when the current page is changed.

## Declaration

Source position: comctrls.pp line 444

`protected procedure TCustomTabControl.Change; virtual;`

## Description

Change is a method used to performs actions needed to show or hide pages in the tabbed control.

Change calls ShowCurrentPage to display the page in PageIndex, and hide the previously visible page in the tabbed control. Change calls DoChange when the control is not being destroyed, or loaded in the LCL component streaming mechanism.

Change is called from the MoveTab method, and when selection change messages are handled for the control.

## Version info

Modified in LCL version 3.4 to call MaybeSelectFirstControlOnPage before OnChange is signalled for the active page.

## See also

TCustomTabControl.ActivePage |  | Caption for the active page in the tabbed control.
TCustomTabControl.MaybeSelectFirstControlOnPage |  | Updates the ActiveControl on the parent form when the specified page becomes active.
TCustomTabControl.PageIndex |  | Ordinal position for the selected page on the tabbed control.
TCustomTabControl.TabIndex |  | Contains the ordinal position for the active Tab in the control.
TCustomTabControl.DoChange |  | Performs actions needed when the active page for the control has been changed.
TCustomTabControl.OnChange |  | Event handler signalled when the active page (or tab) for the control is changed.