MCNotificationCenter

MCNotificationCenter is a replacement for calls to NSNotificationCenter that makes dealing with notifications easier. The singleton class manages and tracks registered observers so you don’t have to! Use MCNotificationCenter to prevent observer-related crashes when registering observers and sending notifications.

Features

• Add and remove observers without worrying about app crashes
• Check if a class is registered as an observer before removing or adding it, or don’t becuase it will handle that automatically ;)
• Can act as a single observer for all KVO needs
• Convenience methods for adding KVO to objects with blocks
• Post a notification only if there is an observer registered, or only if there is a specific class registered as an observer

Installation

Using Cocoapods:

$ pod 'MCNotificationCenter'

Or copy MCNotificationCenter.swift and NSObject+EasyKVO.swift into a project. Add to a bridging header if necessary.

Usage

Check out the example project in the repo for full code samples.

All calls should use the MCNotificationCenter.defaultCenter singleton

MCNotificationCenter.defaultCenter

NSNotificationCenter

Add an observer using one of the provided methods. It follows a similar structure to NSNotificationCenter.

MCNotificationCenter.defaultCenter.addObserver(self, selector: Selector("printNotification:"), name: "myNotification", object: nil)}

Remove an observer. Checking if the observer exists is optional, it’s safe to call remove even if the observer doesn’t exist.

if MCNotificationCenter.defaultCenter.isObserverForName("myNotification", observer: self) {
    MCNotificationCenter.defaultCenter.removeObserverWithName("myNotification", observer: self)
}

Note: You can remove all registered observers for a class or object.

KVO

Add a key value observer with a closure (setting MCNotificationCenter.defaultCenter is required for this functionality. To implement a different observer class, set the class as the observer and nil for the block)

MCNotificationCenter.defaultCenter.addKeyValueObserver(MCNotificationCenter.defaultCenter, onObject: self.myObject, forKeyPath: "someValue", options: .New, context: nil) { () -> () in
        println(self.myObject.someValue)
}

Or use the NSObject+EasyKVO extension which provides convenience methods for using MCNotificationCenter functions

myObject.addObserver("someValue", usingBlock: { () -> () in
     println(self.myObject.value)
})

And remove easily using just the keypath

myObject.removeObserver("someValue")

Class Methods

Check out the files and code comments.

License

• MIT

Enjoy

Questions, comments or ideas? Feel free to send me a message or post an issue.

For fixes, additions, improvements or any other cool stuff pull requests welcome.