NSNotificationDefault Center called multiple times even removing observer before adding - iphone

Question

I am adding observer to init method.And for the reason it will not call multiple times I am removing observer before adding it.Even then is is calling as many times as we load the View.
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
[[NSNotificationCenter defaultCenter] removeObserver:self];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(updateStuff)
name:#"appDidBecomeActive"
object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(closeConnection)
name:#"appDidEnterBackground"
object:nil];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(orientationChanges:)
name:#"UIDeviceOrientationDidChangeNotification"
object:nil];
t=[[Theme alloc] init];
// Custom initialization
}
return self;
}
I have also tried it removing in updateStuff method
-(void)updateStuff
{
[MBProgressHUD hideAllHUDsForView:self.view animated:YES];
NSLog(#"Market Watch update stuff called $$$$$$$----------------------");
[self initNetworkCommunication];
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
also tried removing here.
-(void)dealloc
{
[[NSNotificationCenter defaultCenter] removeObserver:self name:#"appDidBecomeActive" object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self name:#"appDidEnterBackground" object:nil];
[[NSNotificationCenter defaultCenter] removeObserver:self name:#"UIDeviceOrientationDidChangeNotification" object:nil];
}
also tried removing in viewWillDisappear It works fine but here adding observer to viewWillAppear not working.
When I lock the screen and unlock it this observer should call.As it is notified on appDidBecomeActive , and it is working like that. But when I pop back to previous viewController and push to current one and repeats the process of lock and unlock this observer fires two times.As number of times I pop view and push again to current View.Notifier fires number of times I pushed to the View.I know it is because of init method.Whenever view will load it adds an observer but doesn't removes observer.
What can I do other than that.

Answer 1

You have to remove observer in viewWillDisappear method.
-(void)viewWillDisappear:(BOOL)animated
{
[[NSNotificationCenter defaultCenter] removeObserver:self];
}
and remove from initWithNibName.

Answer 2

Try adding it to -awakeFromNib instead
Also, try removing the notification in a different manner. I don't have the code but you have to also give it the name of the notification, and you should only remove observer in dealloc