HowsonLiu
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iOS屏幕旋转

发表于 分类于
被UINavigationController的旋转恶心吐了

设备物理方向

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typedef NS_ENUM(NSInteger, UIDeviceOrientation) {
    UIDeviceOrientationUnknown,
    UIDeviceOrientationPortrait,            // Device oriented vertically, home button on the bottom
    UIDeviceOrientationPortraitUpsideDown,  // Device oriented vertically, home button on the top
    UIDeviceOrientationLandscapeLeft,       // Device oriented horizontally, home button on the right
    UIDeviceOrientationLandscapeRight,      // Device oriented horizontally, home button on the left
    UIDeviceOrientationFaceUp,              // Device oriented flat, face up
    UIDeviceOrientationFaceDown             // Device oriented flat, face down
} API_UNAVAILABLE(tvos);
  • 通过[UIDevice currentDevice].orientation获取
  • Readonly
  • 当打开系统的锁屏开关时，值只为UIDeviceOrientationPortrait

界面显示方向

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// Note that UIInterfaceOrientationLandscapeLeft is equal to UIDeviceOrientationLandscapeRight (and vice versa).
// This is because rotating the device to the left requires rotating the content to the right.
typedef NS_ENUM(NSInteger, UIInterfaceOrientation) {
    UIInterfaceOrientationUnknown            = UIDeviceOrientationUnknown,
    UIInterfaceOrientationPortrait           = UIDeviceOrientationPortrait,
    UIInterfaceOrientationPortraitUpsideDown = UIDeviceOrientationPortraitUpsideDown,
    UIInterfaceOrientationLandscapeLeft      = UIDeviceOrientationLandscapeRight,
    UIInterfaceOrientationLandscapeRight     = UIDeviceOrientationLandscapeLeft
} API_UNAVAILABLE(tvos);
  • 通过[UIApplication sharedApplication].statusBarOrientation获取
  • UIInterfaceOrientationLandscapeLeft = UIDeviceOrientationLandscapeRight：设备向右旋转，界面向左旋转

控制界面旋转方向

1. 配置

  1. 项目配置
  2. plist配置

2. AppDelegate设置

实现下面接口： 

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func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {
        return .allButUpsideDown
    }

3. UIViewController设置

重写下面属性：

  • shouldAutorotate 
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    override var shouldAutorotate: Bool {
        return true
    }
    Interface方向是否跟随设备方向自动旋转，如果false，则后面两个方法不会掉用
  • supportedInterfaceOrientations 
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    override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .portrait
    }
    返回支持的方向，iPhone默认值为UIInterfaceOrientationMaskAllButUpsideDown，iPad默认值为UIInterfaceOrientationMaskAll
  • preferredInterfaceOrientationForPresentation 
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    override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
        return .portrait
    }
    返回最优先显示的屏幕方向

结果

  • UIViewController的方向为这三个设置的交集
  • 设置3仅在以下两种情况才会生效：
    • 当前viewController为window的rootViewController
    • 当前viewController被presentModalViewController出来

特殊VC的界面旋转方向

UINavigationController

当rootViewController为UINavigationController时，界面的旋转方向由UINavigationController控制而并非由push到里面的VC控制

  • 网络上面提供的解决方案
    继承UINavigationController，重写其三个方法 
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    override var shouldAutorotate: Bool {
        return self.topViewController?.shouldAutorotate ?? true
    }

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

    override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
        return self.topViewController?.preferredInterfaceOrientationForPresentation ?? .portrait
    }
  • Apple提供的方案
    实现UINavigationControllerDelegate 
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    func navigationControllerSupportedInterfaceOrientations(_ navigationController: UINavigationController) -> UIInterfaceOrientationMask {
        return self.topViewController?.supportedInterfaceOrientations ?? .portrait
    }

两种方案的原理实际上是一样的，但是实际展现的效果都有缺陷

例如，先往navigationController推一个只支持.landscape的viewController A，然后再推一个只支持.portrait的viewController B。这时候界面并不会在push B的时候立刻变成.portrait，需要旋转一下设备，触发一下系统的回调，才能跑到设置3的回调里面去。pop的时候亦是如此

目前的解决方案

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override func viewDidLoad() {
    super.viewDidLoad()
    let value = UIInterfaceOrientation.portrait.rawValue
    UIDevice.current.setValue(value, forKey: "orientation")
}

强制旋转