In one of my view controller, it adds itself as observer of UITextViewTextDidEndEditingNotification notification, like the following does
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(done:) name:UITextViewTextDidEndEditingNotification object:nil];
Now I am wondering - do I need to do the following when the view controller is dealloc'd
[[NSNotificationCenter defaultCenter] removeObserver:self];