如何将 UIApplicationDelegateAdaptor 用作 ObservableObject？

Question

在我的 iOS 14 App 中，我可以通过以下方式注册遗产 AppDelegate：

@main
struct MyApp: App {
    
    #if os(iOS)
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
    #endif
    
    var body: some Scene {
        ...
    }
}

#if os(iOS)
class AppDelegate: NSObject, UIApplicationDelegate {
    
    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]? = nil) -> Bool {
        SomeSDK.configure(with: launchOptions)
        return true
    }
}
#endif

但是，我在 the documentation 中注意到您可以将 UIApplicationDelegateAdaptor 设为 ObservableObject 然后它会将其注入 EnvironmentObject:

...delegate will be placed in the Environment and may be accessed by using the @EnvironmentObject property wrapper in the view hierarchy.

我找不到任何示例说明它是如何工作的。使此工作成为 ObservableObject 的语法是什么？

Answer 1

这是一个使用演示

确认AppDelegate到ObservableObject

class AppDelegate: NSObject, UIApplicationDelegate, ObservableObject {
    @Published var value: String = ""

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey : Any]? = nil) -> Bool {

        self.value = "test" // in any callback use your published property
        return true
    }
}

像您一样将您的 AppDelegate 注册为适配器

@main
struct Testing_SwiftUI2App: App {
    @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate

    // ... other code

在您的某些视图中根据需要声明@EnvironmentObject

struct ContentView: View {
    @EnvironmentObject var appDelegate: AppDelegate    // << inject

    var body: some View {
       Text("Value: \(appDelegate.value)")  // << use
    }
}

测试 Xcode 12 / iOS 14.

backup

如何将 UIApplicationDelegateAdaptor 用作 ObservableObject？

How to use UIApplicationDelegateAdaptor as ObservableObject?

ios

appdelegate

swift

swiftui

ios14