Using application:handleWatchKitExtensionRequest:reply: to pass Strings

AppDelegate.swift

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    func application(application: UIApplication, handleWatchKitExtensionRequest userInfo: [NSObject : AnyObject]?, reply: (([NSObject : AnyObject]!) -> Void)!) {
        
        // expect a request String from the parent application
        // send a response String in return
        // Note: you may not see these in the console if debugging WatchKit
        if let request: String = userInfo?["request"] as? String {
            println("request: \(request)")
        } else {
            println("request received but not recognised")
        }
        
        var response: [NSObject: AnyObject] = [:]
        response["response"] = "This is a String"
        reply(response)
    }

}