Use opacity modifier instead of conditionals to hide unselected timelines to retain scroll positions

Changelog-Fixed: Use opacity modifier instead of conditionals to hide unselected timelines to retain scroll positions

damus/ContentView.swift

@@ -153,26 +153,25 @@ struct ContentView: View {
     }
     
     func MainContent(damus: DamusState) -> some View {
-        VStack {
-            switch selected_timeline {
-            case .search:
-                if #available(iOS 16.0, *) {
-                    SearchHomeView(damus_state: damus_state!, model: SearchHomeModel(damus_state: damus_state!))
-                        .scrollDismissesKeyboard(.immediately)
-                } else {
-                    // Fallback on earlier versions
-                    SearchHomeView(damus_state: damus_state!, model: SearchHomeModel(damus_state: damus_state!))
-                }
-                
-            case .home:
-                PostingTimelineView
-                
-            case .notifications:
-                NotificationsView(state: damus, notifications: home.notifications)
-                
-            case .dms:
-                DirectMessagesView(damus_state: damus_state!, model: damus_state!.dms, settings: damus_state!.settings)
+        ZStack {
+            if #available(iOS 16.0, *) {
+                SearchHomeView(damus_state: damus_state!, model: SearchHomeModel(damus_state: damus_state!))
+                    .scrollDismissesKeyboard(.immediately)
+                    .opacity(selected_timeline == .search ? 1 : 0)
+            } else {
+                // Fallback on earlier versions
+                SearchHomeView(damus_state: damus_state!, model: SearchHomeModel(damus_state: damus_state!))
+                    .opacity(selected_timeline == .search ? 1 : 0)
             }
+
+            PostingTimelineView
+                .opacity(selected_timeline == .home ? 1 : 0)
+
+            NotificationsView(state: damus, notifications: home.notifications)
+                .opacity(selected_timeline == .notifications ? 1 : 0)
+
+            DirectMessagesView(damus_state: damus_state!, model: damus_state!.dms, settings: damus_state!.settings)
+                .opacity(selected_timeline == .dms ? 1 : 0)
         }
         .navigationBarTitle(timeline_name(selected_timeline), displayMode: .inline)
         .toolbar {

damus/Views/DirectMessagesView.swift

@@ -18,6 +18,7 @@ struct DirectMessagesView: View {
     @State var dm_type: DMType = .friend
     @ObservedObject var model: DirectMessagesModel
     @ObservedObject var settings: UserSettingsStore
+    @SceneStorage("ContentView.selected_timeline") var selected_timeline: Timeline = .home
 
     func MainContent(requests: Bool) -> some View {
         ScrollView {
@@ -90,10 +91,12 @@ struct DirectMessagesView: View {
             .tabViewStyle(.page(indexDisplayMode: .never))
         }
         .toolbar {
-            ToolbarItem(placement: .navigationBarTrailing) {
-                if would_filter_non_friends_from_dms(contacts: damus_state.contacts, dms: self.model.dms) {
-                    
-                    FriendsButton(filter: $settings.friend_filter)
+            if selected_timeline == .dms {
+                ToolbarItem(placement: .navigationBarTrailing) {
+                    if would_filter_non_friends_from_dms(contacts: damus_state.contacts, dms: self.model.dms) {
+
+                        FriendsButton(filter: $settings.friend_filter)
+                    }
                 }
             }
         }

damus/Views/Notifications/NotificationsView.swift

@@ -82,7 +82,8 @@ struct NotificationsView: View {
     @ObservedObject var notifications: NotificationsModel
     @StateObject var filter = NotificationFilter()
     @SceneStorage("NotificationsView.filter_state") var filter_state: NotificationFilterState = .all
-    
+    @SceneStorage("ContentView.selected_timeline") var selected_timeline: Timeline = .home
+
     @Environment(\.colorScheme) var colorScheme
     
     var mystery: some View {