如何防止ARSCNView在方向更改期间旋转

时间:2017-10-03 23:41:55

标签: ios scenekit arkit arscnview

我正在使用ARKit,我希望允许用户在纵向和横向模式下使用该应用程序。 除了ARSCNView之外,我希望所有UI控件都可以在方向更改时旋转。 我试图在相反的方向上转换sceneView但是没有用。

override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        super.viewWillTransition(to: size, with: coordinator)

        let targetRotation = coordinator.targetTransform
        let inverseRotation = targetRotation.inverted()

        coordinator.animate(alongsideTransition: { (context) in
            self.sceneView.transform = self.sceneView.transform.concatenating(inverseRotation)
            context.viewController(forKey: UITransitionContextViewControllerKey.from)
        }, completion: nil)

    }

如何阻止ARKit会话的场景视图旋转,同时允许所有其他UI控件在方向更改时旋转?

1 个答案:

答案 0 :(得分:0)

您无法在视图的基础上指定设备轮换规则。它必须在视图控制器的基础上设置。这就是iOS的工作原理。因此,要实现您所需要的,您必须自己处理。例如,如果您将ARSCNView显示为全屏视图,则可以将其显示在自定义UIViewController子类中,并设置该控制器的旋转配置。

为特定视图控制器设置支持的视图旋转可以通过多种方式实现,下面是其中一些。

方法#1:

您可以通过覆盖应用代理的方法UIViewController来为任何application:supportedInterfaceOrientationsForWindow:设置支持的视图方向。

示例代码:

// this goes into your AppDelegate...
// Basically, this checks the current visible view controller  type  and  decide 
// what orientations your app supports based on that view controller type (class)
func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {
    let visibleViewController = self.topViewController(withRootViewController: window?.rootViewController)

    // Support only portrait orientation for a specific view controller
    if visibleViewController is SomeViewController {
        return .portrait
    }

    // Otherwise, support all orientations (standard behaviour)
    return .allButUpsideDown
}

// This simple helper method is to extract the exact visible  view  controller  at
// the moment, as `window.rootViewController` could have some container controller 
// like `UINavigationController` or so that holds more controllers into it
private func topViewController(withRootViewController rootViewController: UIViewController?) -> UIViewController? {
    if let rootViewController = rootViewController as? UITabBarController {
        return rootViewController.selectedViewController
    } else if let rootViewController = rootViewController as? UINavigationController {
        return rootViewController.visibleViewController
    } else if let presentedViewController = rootViewController?.presentedViewController {
        return topViewController(withRootViewController: presentedViewController)
    }
    return rootViewController
}

参考:

application:supportedInterfaceOrientationsForWindow: method documentation

方法#2:

对您的UINavigationController进行子类并覆盖以下属性:

override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    return self.topViewController?.supportedInterfaceOrientations ?? .all
}

现在,它始终会查看视图控制器的supportedInterfaceOrientations,并根据返回值设置支持的方向。这样做可以让您在所需的任何视图控制器中简单地覆盖它,设置一些自定义值。

例如,在SomeViewController中,您只需添加:

override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
    return .portrait
}

参考:

supportedInterfaceOrientations property documentation

方法#3:

如果您不想在上面的方法#2中对UINavigationController进行细分,则可以将SomeViewController设置为实施navigationControllerSupportedInterfaceOrientations(:)

的导航控制器代理

示例代码:

override func viewDidLoad() {
    super.viewDidLoad()

    // ...

    self.navigationController?.delegate = self
}

// MARK: - UINavigationControllerDelegate

func navigationControllerSupportedInterfaceOrientations(_ navigationController: UINavigationController) -> UIInterfaceOrientationMask {
    return navigationController.topViewController?.supportedInterfaceOrientations ?? .all
}

参考:

Matt's answer here