我应该在哪里删除通知观察员？

Question

I set up a notification observer in my view controller's init method like so:

[[NSNotificationCenter defaultCenter] 
                    addObserver:self
                    selector:@selector(saveState)
                    name:UIApplicationWillResignActiveNotification
                    object:nil];

Where is the best place to call removeObserver:name:object: for this notification. I'm currently calling it in my dealloc method, but wanted to know if that might cause problems.

Answer 1

No, you got it right. dealloc is the correct location to remove notification observers (unless you have some specific reason to need to remove the observer earlier).

Answer 2

您始终可以在viewWillDisappear:删除观察者viewWillDisappear:或者当您完成使用它并且没有其它需要时，可以将其放在函数中。

Answer 3

如果-saveState只需要在活动时执行一次，那么您可以在-saveState中删除Observer。