Invoked to inform the receiver that the value of a given property is about to change.
Original signature is '- (void)willChangeValueForKey:(NSString *)key'
Available in Mac OS X v10.3 and later.
- key (NSString)
- The name of the property that will change.
Assembly: Monobjc.Foundation (Module: Monobjc.Foundation)
- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)