Ios 在Swift中按取消按钮时，Replaykit窗口不会关闭？

我用回放工具来记录我的屏幕，当预览屏幕弹出时，会有一个取消按钮来关闭屏幕，但它什么也不做。我让委托函数PreviewcontrollerdFinish与代码一起关闭它，但它不会消失。有人知道按“取消”时如何关闭窗口吗？谢谢

func previewControllerDidFinish(previewController: RPPreviewViewController) {
    print("Preview finish")

        // close preview window
        previewController.dismissViewControllerAnimated(true, completion: nil)
    }

在swift 3.2中

第一:

class ViewController: UIViewController, RPPreviewViewControllerDelegate {

func previewControllerDidFinish(_ previewController: RPPreviewViewController) {
        previewController.dismiss(animated: true, completion: nil)
    }
}

然后当停止录制按钮调用时，将委托设置为Close

if RPScreenRecorder.shared().isRecording {
RPScreenRecorder.shared().stopRecording { (previewController: RPPreviewViewController?, error: Error?) in
    if previewController != nil {
        let alertController = UIAlertController(title: "Recoring", message: "Do you wish to discard or view your recording?", preferredStyle: .alert)
        let discardAction = UIAlertAction(title: "Discard", style: .destructive, handler: nil)

        let viewAction = UIAlertAction(title: "View", style: .default, handler: { (action: UIAlertAction) in

            // set delegate here
            previewController?.previewControllerDelegate = self

            self.present(previewController!, animated: true, completion: nil)
        })

        alertController.addAction(discardAction)
        alertController.addAction(viewAction)
        self.present(alertController, animated: true, completion: nil)
    }
}

---

}尝试执行此委托

- (void)previewController:(RPPreviewViewController *)previewController didFinishWithActivityTypes:(nonnull NSSet<NSString *> *)activityTypes {

    [previewController dismissViewControllerAnimated:YES completion:^{

    }];
}

-（void）previewController:（RPPreviewViewController*）previewController未完成activityTypes:（非空NSSet*）activityTypes{
[预览控制器解除查看控制器激活：是完成：^{
}];
}