Question

I need my app to constantly listen for reachability changes and update my views according to the network status, i am thinking about using the notificationcenter, and let all my views listen for changes, but i have no idea how to implement this.

I know how to use the notificationcenter and Reachability but i can’t seem to find a place to implement the Reachability check.

Where should i check for network changes, and notify the other ViewControllers?

I don’t think AppDelegate is the right place, and if i put the Reachability check in a ViewController the network checking is only being performed as long as the ViewController is “active”.

Answer 1

Create a “singleton” Reachability and initialize it at app launch.

Let the singleton check for reachability periodically, e.g. with NSTimer. It can then notify any other active views that registered with NSNotificationCenter.

// AppDelegate.m: 

@property (nonatomic, strong) Reachability *reachability;

// in applicationDidFinishLaunching...
self.reachability = [[Reachability alloc] init]; 

and

// Reachability.m

-(id)init {
   self = [super init];
   if (self) {
     [self setupTheTimer];
   }
   return self;
}