swiftui - UIApplication.didBecomeActiveNotification 未调用 iOS 14

Question

我有一个项目 SceneDelegate我在 SwiftUI View 中使用以下代码:

.onReceive(NotificationCenter.default.publisher(for: UIApplication.didBecomeActiveNotification)) { _ in
    print("Did become active...")
}

它在 iOS 13 中被调用，但是当我在 iOS 14 上运行它时它不会运行。
更多详情: didBecomeActiveNotification当我将应用程序置于后台后将其置于前台时调用，但是当应用程序第一次打开时它不是。但在 iOS 13 中，它会在第一次打开时调用它。
我将 Xcode 从 12.2 更新到 12.3，问题仍然存在。有人可以检查他们是否收到 didBecomeActiveNotification使用 iOS 14 打开应用程序时调用？
知道如何进行这项工作吗？
附注。要在 Xcode 12 上使用 SceneDelegate 创建项目 AppName.app文件应该被删除，然后创建 SceneDelegate.swift和 AppDelegate.swift带有样板代码的文件并编辑 info.plist “Application Scene Manifest”键使其使用SceneDelegate。

Answer 1

我做了一些测试，看来你是对的。我不确定这是错误还是有意的更改。
对我来说唯一可行的解​​决方案是 onReceive + Just + scenePhase :

import Combine
import SwiftUI

struct ContentView: View {
    @Environment(\.scenePhase) private var scenePhase

    var body: some View {
        Text("Test")
            .onReceive(Just(scenePhase)) {
                print("onReceive scenePhase \($0)")
            }
    }
}

下面的其他测试(Xcode 14.3，iOS 12.3):

struct ContentView: View {
    @Environment(\.scenePhase) private var scenePhase

    var body: some View {
        Text("Test")
            // not working on the first launch
            .onReceive(NotificationCenter.default.publisher(for: UIApplication.didBecomeActiveNotification)) { _ in
                print("onReceive didBecomeActiveNotification")
            }
            // not working on the first launch
            .onReceive(NotificationCenter.default.publisher(for: UIApplication.willEnterForegroundNotification)) { _ in
                print("onReceive willEnterForegroundNotification")
            }
            // not working on the first launch
            .onReceive(NotificationCenter.default.publisher(for: UIApplication.didFinishLaunchingNotification)) { _ in
                print("onReceive didFinishLaunchingNotification")
            }
            // **working** on the first launch
            .onReceive(Just(scenePhase)) {
                print("onReceive scenePhase \($0)")
            }
            // not working on the first launch
            .onChange(of: scenePhase) {
                print("onChange scenePhase \($0)")
            }
    }
}