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Reflected Window Message IDs

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A quick way to create an ActiveX control, or other specialized control, is to subclass a window. For more information, see MFC ActiveX Controls: Subclassing a Windows Control.

To prevent the control's container from receiving the window messages sent by a subclassed Windows control, COleControl creates a "reflector" window to intercept certain window messages and send them back to the control. The control, in its window procedure, can then process these reflected messages by taking actions appropriate for an ActiveX control.

The following table shows the messages that are intercepted and the corresponding messages that the reflector window sends.

Message sent by the control Message reflected to the control
WM_COMMAND OCM_COMMAND
WM_CTLCOLORBTN OCM_CTLCOLORBTN
WM_CTLCOLOREDIT OCM_CTLCOLOREDIT
WM_CTLCOLORDLG OCM_CTLCOLORDLG
WM_CTLCOLORLISTBOX OCM_CTLCOLORLISTBOX
WM_CTLCOLORSCROLLBAR OCM_CTLCOLORSCROLLBAR
WM_CTLCOLORSTATIC OCM_CTLCOLORSTATIC
WM_DRAWITEM OCM_DRAWITEM
WM_MEASUREITEM OCM_MEASUREITEM
WM_DELETEITEM OCM_DELETEITEM
WM_VKEYTOITEM OCM_VKEYTOITEM
WM_CHARTOITEM OCM_CHARTOITEM
WM_COMPAREITEM OCM_COMPAREITEM
WM_HSCROLL OCM_HSCROLL
WM_VSCROLL OCM_VSCROLL
WM_PARENTNOTIFY OCM_PARENTNOTIFY
WM_NOTIFY OCM_NOTIFY

Note

If the control runs on a Win32 system, there are several types of WM_CTLCOLOR* messages it may receive. For more information, see WM_CTLCOLORBTN, WM_CTLCOLORDLG, WM_CTLCOLOREDIT, WM_CTLCOLORLISTBOX, WM_CTLCOLORMSGBOX, WM_CTLCOLORSCROLLBAR, WM_CTLCOLORSTATIC.

See also

MFC ActiveX Controls: Subclassing a Windows Control
TN062: Message Reflection for Windows Controls