在 SceneDelegate SwiftUI 上设置 managedObjectContext

Question

我按照入门屏幕教程进行操作，但似乎它主要是 UIKit 的改编版，在 AppDelegate 上我收到以下紫色错误：

Context in environment is not connected to a persistent store coordinator: <NSManagedObjectContext: 0x6000018d5880>

我相信这是在 SceneDelegate 中的设置方式，managedObjectContext 没有被传递到下一个屏幕，这就是我的方式：

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {

    // Use a UIHostingController as window root view controller.
    if let windowScene = scene as? UIWindowScene {
        let window = UIWindow(windowScene: windowScene)

        // Set the MotherView as the root view
        window.rootViewController = UIHostingController(rootView: MotherView().environmentObject(ViewRouter()))
        self.window = window
        window.makeKeyAndVisible()
    }
}

如果我不使用核心数据当然可以。如何在此处集成 ViewRouter()：

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options connectionOptions: UIScene.ConnectionOptions) {

    // Get the managed object context from the shared persistent container.
    let context = (UIApplication.shared.delegate as! AppDelegate).persistentContainer.viewContext

    // Create the SwiftUI view and set the context as the value for the managedObjectContext environment keyPath.
    // Add `@Environment(\.managedObjectContext)` in the views that will need the context.
    let contentView = MotherView().environment(\.managedObjectContext, context)

    // Use a UIHostingController as window root view controller.
    if let windowScene = scene as? UIWindowScene {
        let window = UIWindow(windowScene: windowScene)

        // Set the MotherView as the root view
        window.rootViewController = UIHostingController(rootView: contentView)
        self.window = window
        window.makeKeyAndVisible()
    }
}

我去了this 的帖子，但它对我没有用，有没有办法可以在 SceneDelegate 中解决这个问题？

Answer 1

在任何地方将环境对象附加到构造的内容视图中，例如如下

let contentView = MotherView()
                     .environment(\.managedObjectContext, context)
                     .environmentObject(ViewRouter())