iOS的横竖屏配置主要由以下四部分组成

1. info.plist内Supported interface orientations 配置应用支持的方向

截图

2. 项目Target内勾选应用支持的方向

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3. AppDelegate内配置Application支持的方向

    var orientationLock = UIInterfaceOrientationMask.allButUpsideDown // 默认支持方向
    func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask {
        return self.orientationLock
    }

4. ViewController内配置VC支持的方向

    open override var shouldAutorotate: Bool {
        return false
    }
    
    open override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .portrait
    }
    
    open override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
        return .portrait
    }

如何主动控制屏幕方向

if #available(iOS 16.0, *) {
            vc.setNeedsUpdateOfSupportedInterfaceOrientations()
            // iOS 16以上需要通过scene来实现屏幕方向设置
            let windowScene = UIApplication.shared.connectedScenes.first as? UIWindowScene
            var value: UIWindowScene.GeometryPreferences = .iOS(interfaceOrientations: .all)
            switch mode {
            case .port:
                value = .iOS(interfaceOrientations: .portrait)
            case .land:
                value = .iOS(interfaceOrientations: .landscape)
            case .auto:
                value = .iOS(interfaceOrientations: .all)
            }
            windowScene?.requestGeometryUpdate(value, errorHandler: { error in
                
            })
        } else {
            switch mode {
            case .port:
                /// 强制设置成竖屏
                UIDevice.current.setValue(UIInterfaceOrientation.unknown.rawValue, forKey: "orientation")
                UIDevice.current.setValue(UIInterfaceOrientation.portrait.rawValue, forKey: "orientation")
            case .land:
                /// 强制设置成横屏
                UIDevice.current.setValue(UIInterfaceOrientation.unknown.rawValue, forKey: "orientation")
                UIDevice.current.setValue(UIInterfaceOrientation.landscapeRight.rawValue, forKey: "orientation")
            case .auto:
                /// 设置自动旋转
                UIDevice.current.setValue(UIInterfaceOrientation.unknown.rawValue, forKey: "orientation")
            }
        }

    /// 判断当前屏幕是否是竖屏
    public static func isCurrentScreenPortrait() -> Bool {
        let window = UIApplication.shared.windows.filter {$0.isKeyWindow}.first ?? UIWindow()
        let orientation = window.windowScene?.interfaceOrientation
        switch orientation {
        case .portrait, .portraitUpsideDown:
            return true
        case .landscapeLeft, .landscapeRight:
            return false
        default:
            return true
        }
    }

视图如何适应横竖屏

        if ScreenRotationTool.isCurrentScreenPortrait() == true {
            contentView.snp.remakeConstraints { make in
                ...
            }
        } else {
            contentView.snp.remakeConstraints { make in
                ...
            }
        }

逻辑概述：
iOS按照Application->TabBarVC->NavVC->VC->ChildVC的顺序来调用相关的函数或者属性（info.plist和Target内的配置我也不知道有什么作用），用来确定当前App支持的屏幕方向。
如果Application不支持对应方向，即使ViewController支持该方向，也是没有作用的。

如果你的ViewController没有重写相关的方法，那默认就是支持所有方向的，也就不需要实现VC相关的方法重写，这会节省很多代码。

中间的坑

1. 某些第三方库（如HBDNav），会直接重写ViewController的相关方法，修改VC默认支持的控制器方向，如果它的默认值不是你想要的，这时候你就需要继承来重写相关方法了

2. 屏幕支持方向的传递性，App通常由UITabBarController、UINavigationController、UIViewController、ChildViewController组成，想要让当前的VC来控制，那就需要一层层的调用下去，交由对应的VC去控制

    // TabBarController
    public override var shouldAutorotate: Bool {
        return self.selectedViewController?.shouldAutorotate ?? true
    }

    public override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return self.selectedViewController?.supportedInterfaceOrientations ?? UIInterfaceOrientationMask.allButUpsideDown
    }
    
    public override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
        return self.selectedViewController?.preferredInterfaceOrientationForPresentation ?? .portrait
    }

    // NavigationController
    public override var shouldAutorotate: Bool {
        return self.topViewController?.shouldAutorotate ?? true
    }

    public override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return self.topViewController?.supportedInterfaceOrientations ?? UIInterfaceOrientationMask.allButUpsideDown
    }
    
    public override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
        return self.topViewController?.preferredInterfaceOrientationForPresentation ?? .portrait
    }

    // ViewController(如果有childViewController，需要指定到对应的VC上)
    open override var shouldAutorotate: Bool {
        return false
    }
    
    open override var supportedInterfaceOrientations: UIInterfaceOrientationMask {
        return .portrait
    }
    
    open override var preferredInterfaceOrientationForPresentation: UIInterfaceOrientation {
        return .portrait
    }

3. VC的supportedInterfaceOrientations系统不会每次都调用，要刷新需要调用vc.setNeedsUpdateOfSupportedInterfaceOrientations()

4. 跳转VC的时候，根据下个页面的方向，先保持一致的方向，再跳转

其他的自己摸索下就好了。