我有一个旧的Xcode项目,没有UISceneDelegate
方法。是否可以使用UISceneDelegate
方法将旧的Xcode项目迁移到新的项目,但仍保持与iOS 12的兼容性?
如果是,怎么办?因为我在iOS 14中看到了很多错误,所以唯一的解决方法是使用UISceneDelegate方法。
答案 0 :(得分:1)
在呈现View Controller的视图之后,请确保查询windowOrientation
。通常在viewDidLoad()
和viewWillAppear(_:)
中,view.window
是nil
,请选中此answer。只需检查windowOrientation
中viewDidAppear(_:)
的值即可。
如果您在尝试使用以下定义之前仍遇到访问此值的问题
private var windowOrientation: UIInterfaceOrientation {
if #available(iOS 13.0, *) {
return UIApplication.shared.windows.first?.windowScene?.interfaceOrientation ?? .unknown
} else {
// Fallback on earlier versions
return UIApplication.shared.statusBarOrientation
}
}
我不确定您的应用程序是否使用多个窗口,但是不确定是否只有一个(由于您没有以编程方式创建任何窗口),因此以下定义应该可以正常工作。
var hasTopNotch: Bool {
return UIApplication.shared.windows.first?.safeAreaInsets.top ?? 0 > 20
}
UISceneDelegate
已在iOS 13.0
中引入,因此无法与iOS 12
兼容,您需要完全依赖UIApplicationDelegate
。要为UISceneDelegate
支持iOS 13.x
,您需要添加显式可用性检查以避免编译错误。
Info.plist
中添加场景清单以Info.plist
的身份打开Source Code
并添加以下内容
<key>UIApplicationSceneManifest</key>
<dict>
<key>UIApplicationSupportsMultipleScenes</key>
<false/>
<key>UISceneConfigurations</key>
<dict>
<key>UIWindowSceneSessionRoleApplication</key>
<array>
<dict>
<key>UISceneConfigurationName</key>
<string>Default Configuration</string>
<key>UISceneDelegateClassName</key>
<string>$(PRODUCT_MODULE_NAME).SceneDelegate</string>
<key>UISceneStoryboardFile</key>
<string>Main</string>
</dict>
</array>
</dict>
</dict>
SceneDelegate.swift
文件import UIKit
@available(iOS 13.0, *)
class SceneDelegate: UIResponder, UIWindowSceneDelegate {
var window: UIWindow?
func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {
// Use this method to optionally configure and attach the UIWindow `window` to the provided UIWindowScene `scene`.
// If using a storyboard, the `window` property will automatically be initialized and attached to the scene.
// This delegate does not imply the connecting scene or session are new (see `application:configurationForConnectingSceneSession` instead).
guard let _ = (scene as? UIWindowScene) else { return }
}
func sceneDidDisconnect(_ scene: UIScene) {
// Called as the scene is being released by the system.
// This occurs shortly after the scene enters the background, or when its session is discarded.
// Release any resources associated with this scene that can be re-created the next time the scene connects.
// The scene may re-connect later, as its session was not neccessarily discarded (see `application:didDiscardSceneSessions` instead).
}
func sceneDidBecomeActive(_ scene: UIScene) {
// Called when the scene has moved from an inactive state to an active state.
// Use this method to restart any tasks that were paused (or not yet started) when the scene was inactive.
}
func sceneWillResignActive(_ scene: UIScene) {
// Called when the scene will move from an active state to an inactive state.
// This may occur due to temporary interruptions (ex. an incoming phone call).
}
func sceneWillEnterForeground(_ scene: UIScene) {
// Called as the scene transitions from the background to the foreground.
// Use this method to undo the changes made on entering the background.
}
func sceneDidEnterBackground(_ scene: UIScene) {
// Called as the scene transitions from the foreground to the background.
// Use this method to save data, release shared resources, and store enough scene-specific state information
// to restore the scene back to its current state.
}
}
AppDelegate
UISceneSession Lifecycle
个方法。// MARK: UISceneSession Lifecycle
@available(iOS 13.0, *)
func application(_ application: UIApplication, configurationForConnecting connectingSceneSession: UISceneSession, options: UIScene.ConnectionOptions) -> UISceneConfiguration {
// Called when a new scene session is being created.
// Use this method to select a configuration to create the new scene with.
return UISceneConfiguration(name: "Default Configuration", sessionRole: connectingSceneSession.role)
}
@available(iOS 13.0, *)
func application(_ application: UIApplication, didDiscardSceneSessions sceneSessions: Set<UISceneSession>) {
// Called when the user discards a scene session.
// If any sessions were discarded while the application was not running, this will be called shortly after application:didFinishLaunchingWithOptions.
// Use this method to release any resources that were specific to the discarded scenes, as they will not return.
}
ii)最后参考Apple Documentation。您可以参考https://dev.to/kevinmaarek/add-a-scene-delegate-to-your-current-project-5on了解其他清理和设置任务。