ios - 阻止Speechkit导致iOS 9设备崩溃

我已经将Speechkit大量集成到我的应用程序的视图控制器中。Speechkit仅在iOS 10上可用，但我也需要我的应用程序在iOS 9设备上运行。
现在，我的应用程序在iOS9设备上启动时崩溃；如何防止Speechkit崩溃iOS9及更早版本？我可以创建两个单独的视图控制器文件，还是必须在每个Speechkit引用周围放置if #available(iOS 10, *) {？
编辑：我能做什么来代替这个？

import Speech
class ViewController2: UIViewController, SFSpeechRecognizerDelegate {

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

func doSomeStuffWithSpeech() {
...
}

...

}

最佳答案

我有高度集成的演讲工具包
如果是这样的话，我认为创建两个独立的viewControllers可能更容易，或者更符合逻辑，您可以根据#available(iOS 10.0, *)
假设您将根据点击另一个ViewController中的按钮（在代码片段中，我称之为ViewController2）来显示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)
        }
    }

    //...
}

此外，您可以在声明变量时使用它：

class ViewController: UIViewController {
    //...

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

    //...
}

但是，正如您所提到的，如果您与Speechkit进行了“大量”集成，那么我假设让两个viewcontroller更符合逻辑。
希望这有帮助。