#observing

ORA-16820: fast-start failover observer is no longer observing this database

文档解释ORA-16820:fast-startfailoverobserverisnolongerobservingthisdatabaseCause:Apreviouslystartedobserverwasnolongeractivelyobservingthisdatabase.Asignificantamou...

观察者模式的具体应用——通知(notification)机制和KVO(Key-Value-Observing)机制

    在CocoaTouch框架中,观察者模式的具体应用有两个——通知(notification)机制和KVO(Key-Value-Observing)机制。        ...