WM VRNENABLED

This message tells a window that its visible region is now unlocked and is valid for drawing on. It also contains a message parameter to inform the window if the visible region was changed.

Syntax

param1
    BOOL   ffVisRgnChanged;  /* Flag indicating whether the visible region has been altered. */

param2
    VOID   mp2;              /* Reserved value. */

Parameters

ffVisRgnChanged (BOOL) - input

Flag indicating whether the visible region has been altered.

TRUE: The visible region has been altered. The application needs to query the new visible region.

FALSE: The visible region has not been changed.

mp2 (VOID) - input

Reserved value.

Returns

ulReserved (ULONG) - returns

Reserved value, should be 0.

Remarks

The visible region, in window coordinates, has been sized, moved or unlocked and drawing can now resume. The ffVisRgnChanged parameter is TRUE if the visible region was altered, telling the application whether it needs to recheck the visible area of the window. Direct drawing to the window can be resumed.

Default Processing

The default window procedure takes no action on this message, other than to set ulReserved to 0.