Migrazione del vecchio progetto Xcode a uno nuovo con UISceneDelegate

Question

Ho un vecchio progetto Xcode senza UISceneDelegatemetodi. È possibile migrare un vecchio progetto Xcode a uno nuovo con UISceneDelegatemetodi MA mantenendo la compatibilità con iOS 12?

Se é cosi, come? Perché vedo molti bug in iOS 14 per i quali l'unica soluzione alternativa è l'utilizzo dei metodi UISceneDelegate.

Answer 1

MODIFICA 1:

Assicurati di eseguire una query per windowOrientation, dopo il rendering della vista del controller di visualizzazione. Tipicamente in viewDidLoad()and viewWillAppear(_:), view.windowis nil, controlla questa risposta . Controlla solo il valore windowOrientationin viewDidAppear(_:).

Se hai qualche problema per accedere a questo valore anche prima di provare la seguente definizione

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
    }
}

Non sono sicuro che la tua app utilizzi più finestre o meno, ma se ce n'è solo una (dato che non stai creando nessuna finestra in modo programmatico), la seguente definizione dovrebbe funzionare bene.

var hasTopNotch: Bool {
    return UIApplication.shared.windows.first?.safeAreaInsets.top ?? 0 > 20
}

Risposta originale:

UISceneDelegateè stato introdotto in iOS 13.0modo che non sia compatibile con iOS 12, è necessario dipendere UIApplicationDelegatetotalmente. Per supportare UISceneDelegateper iOS 13.x, è necessario aggiungere un controllo esplicito della disponibilità per evitare errori di compilazione.

Passaggi 1: aggiungi il manifesto della scena in Info.plist

Apri Info.plistcome Source Codee aggiungi quanto segue

<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>

Passaggio 2: creare un SceneDelegate.swiftfile con il seguente contenuto

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.
    }


}

Passaggio 3: aggiornamento AppDelegate

1. Aggiungi UISceneSession Lifecyclemetodi.

// 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) Infine fare riferimento alla documentazione di Apple . Puoi fare riferimento ahttps://dev.to/kevinmaarek/add-a-scene-delegate-to-your-current-project-5on per ulteriori operazioni di pulizia e configurazione.