Adding Observables class

DHBW-Service/App/DHBW_ServiceApp.swift

@@ -10,11 +10,13 @@ import SwiftUI
 @main
 struct DHBW_ServiceApp: App {
     let persistenceController = PersistenceController.shared
+    let settings = LocalSettings()
 
     var body: some Scene {
         WindowGroup {
             ContentView()
                 .environment(\.managedObjectContext, persistenceController.context)
+                .environmentObject(settings)
         }
     }
 }

DHBW-Service/Observables/LocalSettings.swift

@@ -0,0 +1,25 @@
+//
+//  LocalSettings.swift
+//  DHBW-Service
+//
+//  Created by Patrick Müller on 21.12.20.
+//
+
+import Foundation
+import Combine
+
+private var cancellables = [String:AnyCancellable]()
+
+extension Published {
+    init(wrappedValue defaultValue: Value, key: String) {
+        let value = UserDefaults.standard.object(forKey: key) as? Value ?? defaultValue
+        self.init(initialValue: value)
+        cancellables[key] = projectedValue.sink { val in
+            UserDefaults.standard.set(val, forKey: key)
+        }
+    }
+}
+
+class LocalSettings: ObservableObject {
+    @Published(wrappedValue: true, key: "IsFirstOpening") var isFirstOpening: Bool // To determine if the user is logged in
+}

DHBW-Service/Views/ContentView.swift

@@ -9,22 +9,36 @@ import SwiftUI
 import CoreData
 
 struct ContentView: View {
+    @EnvironmentObject var settings: LocalSettings
     @State private var selection = 0
     
     var body: some View {
-        TabView(selection: $selection) {
-            HomeView()
-                .tabItem {
-                    VStack {
-                        Image(systemName: "house.fill")
-                        Text("Home")
-                    }
+        Group {
+            if(!settings.isFirstOpening) {
+                TabView(selection: $selection) {
+                    HomeView()
+                        .tabItem {
+                            VStack {
+                                Image(systemName: "house.fill")
+                                Text("Home")
+                            }
+                        }
+                        .tag(0)
                 }
-                .tag(0)
+            } else {
+                Button(action: {
+                    self.settings.isFirstOpening = !self.settings.isFirstOpening
+                }){
+                    Text("First opening toggle")
+                }
+            }
         }
     }
 }
 
+extension ContentView{
+}
+
 struct ContentView_Previews: PreviewProvider {
     static var previews: some View {
         ContentView()

DHBW-Service/Views/Tabs/HomeView.swift

@@ -8,13 +8,23 @@
 import SwiftUI
 
 struct HomeView: View {
+    @EnvironmentObject var settings: LocalSettings
+    
     var body: some View {
-        Text(/*@START_MENU_TOKEN@*/"Hello, World!"/*@END_MENU_TOKEN@*/)
+        VStack {
+            Button(action: {
+                self.settings.isFirstOpening = !self.settings.isFirstOpening
+            }){
+                Text("First opening toggle")
+            }
+            Text("Test")
+        }
     }
 }
 
 struct HomeView_Previews: PreviewProvider {
     static var previews: some View {
         HomeView()
+            .preferredColorScheme(.dark)
     }
 }