mac screensaver start event

Question

Is there an event fired when screensaver starts? Like for keychain locking:

OSStatus keychain_locked(SecKeychainEvent keychainEvent, SecKeychainCallbackInfo *info, void *context){...}

Answer 1

Finally found it — the solution is to use NSDistributedNotificationCenter and observe folowing events

• com.apple.screensaver.didstart
• com.apple.screensaver.willstop
• com.apple.screensaver.didstop
• com.apple.screenIsLocked
• com.apple.screenIsUnlocked

Like

[[NSDistributedNotificationCenter defaultCenter]
   addObserver:self
   selector:@selector(screensaverStarted:)
   name:@"com.apple.screensaver.didstart"
   object:nil];