我有一个没有UISceneDelegate
方法的旧 Xcode 项目。是否可以使用方法将旧 Xcode 项目迁移到新项目,UISceneDelegate
但仍保持与 iOS 12 的兼容性?
如果是这样,怎么做?因为我在 iOS 14 中看到了很多错误,唯一的解决方法是使用 UISceneDelegate 方法。
我有一个没有UISceneDelegate
方法的旧 Xcode 项目。是否可以使用方法将旧 Xcode 项目迁移到新项目,UISceneDelegate
但仍保持与 iOS 12 的兼容性?
如果是这样,怎么做?因为我在 iOS 14 中看到了很多错误,唯一的解决方法是使用 UISceneDelegate 方法。
确保windowOrientation
在 View Controller 的视图呈现后查询。通常在viewDidLoad()
and viewWillAppear(_:)
, view.window
is nil
, 检查这个答案。只需检查windowOrientation
in 的值viewDidAppear(_:)
。
如果您在尝试以下定义之前访问此值有一些问题
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,但如果只有一个(因为您没有以编程方式创建任何窗口),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
已经引入iOS 13.0
所以无法兼容iOS 12
,需要完全依赖UIApplicationDelegate
。要支持UISceneDelegate
for iOS 13.x
,您需要添加显式可用性检查以避免编译错误。
Info.plist
打开Info.plist
为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
具有以下内容的文件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
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 文档。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。