Notifies the delegate that the window is about to open a sheet.
Original signature is '- (void)windowWillBeginSheet:(NSNotification *)notification'
Available in Mac OS X v10.1 and later.
- notification (NSNotification)
- A notification named NSWindowWillBeginSheetNotification.
Assembly: Monobjc.AppKit (Module: Monobjc.AppKit)
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)