如何使用NSNotification

Question

In my application there is two viewControllers as FirstViewController and DetailViewController . When tap on a table cell, it navigate to DetailViewController . In DetailViewController , I want to edit and reload the FirstViewController 's table view

How can I use NSNotification for this problem?

Here's the method I want to implement NSNotification stuff

-(IBAction) save{
strSelectedText=theTextField.text;

[NSNotificationCenter defaultCenter];
NSNotification* notification = [NSNotification notificationWithName:@"MyNotification" object:self];
[[NSNotificationCenter defaultCenter] postNotification:notification];  

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector (objFirstViewController) name:@"MyNotification" object:nil];



[self.navigationController popViewControllerAnimated:YES];
}

Answer 1

-(void)viewDidLoad {

[NSNotificationCenter defaultCenter];
NSNotification* notification = [NSNotification notificationWithName:@"MyNotification" object:self];
[[NSNotificationCenter defaultCenter] postNotification:notification];  

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector (objFirstViewController) name:@"MyNotification" object:nil];

}


-(IBAction) save{

[[NSNotificationCenter defaultCenter] postNotificationName:MyNotification object:sender];

//this will go to where you implement your selector objFirstViewController.

}

-(void)objFirstViewController:(NSNotification *)notification {

}

Answer 2

post the notification from detailViewController and add firstViewController as the observer.

Make sure you remove fireViewController from the observer list from viewDidUnload.

Right now you are adding detailViewController as observer.