1.首先在Xcode工程设定中，确认横屏和竖屏都是打开的。

2.在AppDelegate中。

//当前界面支持的方向（默认情况下只能竖屏，不能横屏显示）
    var interfaceOrientations:UIInterfaceOrientationMask = .portrait{
        didSet{
            //强制设置成竖屏
            if interfaceOrientations == .portrait{
                UIDevice.current.setValue(UIInterfaceOrientation.portrait.rawValue,
                                          forKey: "orientation")
            }
            //强制设置成横屏
            else if !interfaceOrientations.contains(.portrait){
                UIDevice.current.setValue(UIInterfaceOrientation.landscapeLeft.rawValue,
                                          forKey: "orientation")
            }
        }
    }
    //返回当前界面支持的旋转方向
    func application(_ application: UIApplication, supportedInterfaceOrientationsFor
        window: UIWindow?)-> UIInterfaceOrientationMask {
        return interfaceOrientations
    }

3.在swiftUI的View画面中，可以控制横屏和竖屏幕变换。

struct XXXXXView: View {
    
    var body: some View {
        ZStack(alignment: .bottom) {
            xxxxxxx
            
        }.frame(alignment: .bottom)
        .onAppear() {
            let appDelegate = UIApplication.shared.delegate as! AppDelegate
            appDelegate.interfaceOrientations = [.landscapeRight]
        }.onDisappear() {
            let appDelegate = UIApplication.shared.delegate as! AppDelegate
            appDelegate.interfaceOrientations = .portrait
        }
   
    }