Stopping Speechkit from crashing iOS 9 devices

Question

I have heavily integrated Speechkit into one of my app's view controllers. Speechkit is only available on iOS 10, but I also need my app to run on iOS 9 devices.

Right now, my app crashes on launch on iOS 9 devices; how can I prevent Speechkit from crashing iOS versions 9 and earlier? Can I create two separate view controller files, or do I have to put if #available(iOS 10, *) { around every single Speechkit reference?

Edit: What can I do instead of this?

import Speech
class ViewController2: UIViewController, SFSpeechRecognizerDelegate {

if #available(iOS 9, *) { // ERROR: Expected Declaration
private let speechRecognizer = SFSpeechRecognizer(locale: Locale(identifier: "en-US"))!
}

func doSomeStuffWithSpeech() {
...
}

...

}

Answer 1

I have heavily integrated Speechkit

If that's the case, I think creating two separated viewControllers might be easier -or more logical-, you can decide which one should viewed based on the #available(iOS 10.0, *)

Let's assume that you will present the ViewController2 based on tapping a button in another ViewController (In the code snippet, I called it PreviousViewController):

class PreviousViewController: UIViewController {
    //...

    @IBAction func presentApproriateScene(sender: AnyObject) {
        if #available(iOS 10.0, *) {
            // present the ViewController that heavily integrated with Speechkit
            // maybe by perfroming a segue:
            performSegueWithIdentifier("segue01", sender: self)

            // or maybe by getting the it from the storyboard
            let storyboard = UIStoryboard(name: "Main", bundle: nil)
            let vc1 = storyboard.instantiateViewControllerWithIdentifier("vc1")
            presentViewController(vc1, animated: true, completion: nil)

        } else {
            // present the ViewController that does not suupport Speechkit
            // maybe by perfroming a segue:
            performSegueWithIdentifier("segue02", sender: self)

            // or maybe by getting the it from the storyboard
            let storyboard = UIStoryboard(name: "Main", bundle: nil)
            let vc2 = storyboard.instantiateViewControllerWithIdentifier("vc2")
            presentViewController(vc2, animated: true, completion: nil)
        }
    }

    //...
}

Also, you can use it when declaring variables:

class ViewController: UIViewController {
    //...

    if #available(iOS 10.0, *) {
        private let speechRecognizer = SFSpeechRecognizer(locale: Locale(identifier: "en-US"))!
    } else {
        // ...
    }

    //...
}

But again, as you mentioned, if you have "heavy" integration with Speechkit, I assume that making two Viewcontrollers would be more logical.

Hope this helped.