Interface Controllers

Now the SessionManager class is ready to test. To do this, we simply need to create the sharedInstance in the InterfaceController class which we will now implement.

In the project navigator, select InterfaceController.swift, and add the following code to the InterfaceController class's awakeWithContext method:

    override func awakeWithContext(context: AnyObject?) {
        super.awakeWithContext(context)
        requestWeatherData()
    }

The compiler will complain about not knowing any such method, so we'll fix that now.

Add the following function to the InterfaceController class:

    func requestWeatherData() { //1
        WeatherSessionManager.sharedInstance.fetchWeatherData() { //2
            (data: NSData?, response: NSURLResponse?, taskError: NSError?) -> Void in
            if taskError == nil { //3
                do {
                    let jsonData = try NSJSONSerialization.JSONObjectWithData(
                        data!,
                        options...