“ iPhone应用程序中的UIApplicationDelegate从未调用reply（）”错误突然

Question

I recently reverted back to a previous version of my app through my Time Capsule backup, and everything is working as it should be with the exception of one thing. When I try to use the watch extension for my app, it never receives a reply from the parent application. I haven't changed any code, but it doesn't work no matter what. Even if I just send an empty request and a simple string back, I get the same error:

The UIApplicationDelegate in the iPhone App never called reply()

This is (the simplified version of) my code:

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

    WKInterfaceController.openParentApplication(["test": "test"]) { userInfo, error in
        println("User Info: \(userInfo)")
        println("Error: \(error)")
    }        
}

Delegate:

func application(application: UIApplication, handleWatchKitExtensionRequest userInfo: [NSObject : AnyObject]?, reply: (([NSObject : AnyObject]!) -> Void)!) {
    let favouritesArrayDefaults = NSUserDefaults.standardUserDefaults().arrayForKey("favourites")!

    if let pfqueryRequest: AnyObject = (userInfo as? [String: AnyObject])?["parkName"] {
    } else {
        let taskID = beginBackgroundUpdateTask()

        reply(["Success": "Success"])

        endBackgroundUpdateTask(taskID)
    }
}

Anyone have any ideas?

Answer 1

You are supposed to call the watch's reply function immediately. You can't wait until an async function completes. By then the watch has given up and decided the phone isn't going to reply. I can't find the statement to that effect in Apple's docs any more, but I do remember reading it.

Answer 2

Your code does not call the replyBlock in the first if block (before the else). Might that be the code path that you see the error log for?

Answer 3

Figured it out! The line:

let favouritesArrayDefaults = NSUserDefaults.standardUserDefaults().arrayForKey("favourites")!

Would crash if the array was empty. This was the first time I had tried the watch app with an empty array in the main app so that was why it had never occurred before.