CM PAINTBACKGROUND

This message informs an application whenever a container's background is painted if the CA_OWNERPAINTBACKGROUND attribute of the CNRINFO data structure is specified.

Syntax

param1
POWNERBACKGROUND pOwnerBackground; /* Pointer to the OWNERBACKGROUND structure. */

param2
ULONG ulReserved;                /* Reserved value, should be 0. */

Parameters

pOwnerBackground (POWNERBACKGROUND) - Input

Pointer to the OWNERBACKGROUND structure.

ulReserved (ULONG) - Input

Reserved value, should be 0.

Returns

rc (BOOL) - returns

Process indicator.

TRUE: The application processed the CM_PAINTBACKGROUND message.

FALSE: The application did not process the CM_PAINTBACKGROUND message.

Remarks

The CM_PAINTBACKGROUND message is provided so that an application can subclass the container control and paint its own background. If the application does not subclass the container control or subclasses the container control and returns FALSE, the container uses the system window color, which is specified by SYSCLR_WINDOW. This color can be changed by using the PP_BACKGROUNDCOLOR or PP_BACKGROUNDCOLORINDEX presentation parameter of the WM_PRESPARAMCHANGED (in Container Controls) message.

Default Processing

The default window procedure does not expect to receive this message and therefore takes no action on it other than to return FALSE.