fix: preserve live TV state across refreshes

lib/screens/livetv/live_tv_screen.dart

@@ -72,6 +72,9 @@ class _LiveTvScreenState extends State<LiveTvScreen>
   final Map<String, String> _favoriteStoreByChannel = {};
   final Map<String, String> _favoriteStoreBySource = {};
   final Map<String, FavoriteChannelPersistenceMode> _favoriteModeByStore = {};
+  Future<void>? _channelsLoadFuture;
+  int _favoritesLoadGeneration = 0;
+  int _favoritesMutationGeneration = 0;
 
   List<LiveTvChannel> get _filteredChannels => filterLiveTvChannelsForFavorites(
     channels: _channels,
@@ -268,7 +271,18 @@ class _LiveTvScreenState extends State<LiveTvScreen>
     return trimmed == null || trimmed.isEmpty ? null : trimmed;
   }
 
-  Future<void> _loadChannels() async {
+  Future<void> _loadChannels() {
+    final inFlight = _channelsLoadFuture;
+    if (inFlight != null) return inFlight;
+    late final Future<void> load;
+    load = _loadChannelsOnce().whenComplete(() {
+      if (identical(_channelsLoadFuture, load)) _channelsLoadFuture = null;
+    });
+    _channelsLoadFuture = load;
+    return load;
+  }
+
+  Future<void> _loadChannelsOnce() async {
     if (!mounted) return;
     setState(() {
       _isLoading = true;
@@ -289,12 +303,12 @@ class _LiveTvScreenState extends State<LiveTvScreen>
 
       final allChannels = <LiveTvChannel>[];
       final seenChannels = <String>{};
-      _favoriteSourceByLiveServer.clear();
+      final favoriteSourceByLiveServer = <String, String>{};
-      _favoriteSourceByChannel.clear();
+      final favoriteSourceByChannel = <String, String>{};
-      _favoriteStoreByLiveServer.clear();
+      final favoriteStoreByLiveServer = <String, String>{};
-      _favoriteStoreByChannel.clear();
+      final favoriteStoreByChannel = <String, String>{};
-      _favoriteStoreBySource.clear();
+      final favoriteStoreBySource = <String, String>{};
-      _favoriteModeByStore.clear();
+      final favoriteModeByStore = <String, FavoriteChannelPersistenceMode>{};
 
       appLogger.d(
         'Live TV DVRs: ${liveTvServers.map((s) => '${s.serverId}/${s.dvrKey} lineup=${s.lineup}').join(', ')}',
@@ -319,10 +333,10 @@ class _LiveTvScreenState extends State<LiveTvScreen>
           final sourceTitle = _sourceTitleForServerInfo(serverInfo);
           final storeKey = liveTv.favoriteStoreKey;
           final liveServerKey = _liveServerScopeKey(serverInfo);
-          _favoriteSourceByLiveServer[liveServerKey] = source;
+          favoriteSourceByLiveServer[liveServerKey] = source;
-          _favoriteStoreByLiveServer[liveServerKey] = storeKey;
+          favoriteStoreByLiveServer[liveServerKey] = storeKey;
-          _favoriteStoreBySource[source] = storeKey;
+          favoriteStoreBySource[source] = storeKey;
-          _favoriteModeByStore[storeKey] = liveTv.favoritePersistenceMode;
+          favoriteModeByStore[storeKey] = liveTv.favoritePersistenceMode;
 
           final channels = await genericClient.liveTv.fetchChannels(lineup: serverInfo.lineup);
           // Plex's DVR exposes a separate enabled-channel mapping; Jellyfin
@@ -342,8 +356,8 @@ class _LiveTvScreenState extends State<LiveTvScreen>
             final dedupKey = liveTvChannelScopeKey(scopedChannel);
             if (seenChannels.add(dedupKey)) {
               final scopeKey = liveTvChannelScopeKey(scopedChannel);
-              _favoriteSourceByChannel[scopeKey] = source;
+              favoriteSourceByChannel[scopeKey] = source;
-              _favoriteStoreByChannel[scopeKey] = storeKey;
+              favoriteStoreByChannel[scopeKey] = storeKey;
               allChannels.add(scopedChannel);
             }
           }
@@ -364,6 +378,24 @@ class _LiveTvScreenState extends State<LiveTvScreen>
 
       setState(() {
         _channels = allChannels;
+        _favoriteSourceByLiveServer
+          ..clear()
+          ..addAll(favoriteSourceByLiveServer);
+        _favoriteSourceByChannel
+          ..clear()
+          ..addAll(favoriteSourceByChannel);
+        _favoriteStoreByLiveServer
+          ..clear()
+          ..addAll(favoriteStoreByLiveServer);
+        _favoriteStoreByChannel
+          ..clear()
+          ..addAll(favoriteStoreByChannel);
+        _favoriteStoreBySource
+          ..clear()
+          ..addAll(favoriteStoreBySource);
+        _favoriteModeByStore
+          ..clear()
+          ..addAll(favoriteModeByStore);
         _isLoading = false;
       });
 
@@ -389,10 +421,13 @@ class _LiveTvScreenState extends State<LiveTvScreen>
   }
 
   Future<void> _loadFavorites(MultiServerProvider multiServer) async {
+    final loadGeneration = ++_favoritesLoadGeneration;
+    final mutationGeneration = _favoritesMutationGeneration;
     try {
-      _favoriteSourceByLiveServer.clear();
+      final sourceByLiveServer = Map<String, String>.of(_favoriteSourceByLiveServer);
-      _favoriteStoreBySource.clear();
+      final storeByLiveServer = Map<String, String>.of(_favoriteStoreByLiveServer);
-      _favoriteModeByStore.clear();
+      final storeBySource = Map<String, String>.of(_favoriteStoreBySource);
+      final modeByStore = Map<String, FavoriteChannelPersistenceMode>.of(_favoriteModeByStore);
       final merged = <FavoriteChannel>[];
       final fetchedStores = <String>{};
       final seenFavorites = <String>{};
@@ -403,20 +438,36 @@ class _LiveTvScreenState extends State<LiveTvScreen>
         final source = await liveTv.buildFavoriteChannelSource(lineup: serverInfo.lineup);
         final storeKey = liveTv.favoriteStoreKey;
         final liveServerKey = _liveServerScopeKey(serverInfo);
-        _favoriteSourceByLiveServer[liveServerKey] = source;
+        sourceByLiveServer[liveServerKey] = source;
-        _favoriteStoreByLiveServer[liveServerKey] = storeKey;
+        storeByLiveServer[liveServerKey] = storeKey;
-        _favoriteStoreBySource[source] = storeKey;
+        storeBySource[source] = storeKey;
-        _favoriteModeByStore[storeKey] = liveTv.favoritePersistenceMode;
+        modeByStore[storeKey] = liveTv.favoritePersistenceMode;
         if (!fetchedStores.add(storeKey)) continue;
         final serverFavorites = await liveTv.fetchFavoriteChannels();
         for (final favorite in serverFavorites) {
-          _favoriteStoreBySource[favorite.source] = storeKey;
+          storeBySource[favorite.source] = storeKey;
           if (seenFavorites.add(favorite.stableKey)) merged.add(favorite);
         }
       }
 
-      if (!mounted) return;
+      if (!mounted ||
+          loadGeneration != _favoritesLoadGeneration ||
+          mutationGeneration != _favoritesMutationGeneration) {
+        return;
+      }
       setState(() {
+        _favoriteSourceByLiveServer
+          ..clear()
+          ..addAll(sourceByLiveServer);
+        _favoriteStoreByLiveServer
+          ..clear()
+          ..addAll(storeByLiveServer);
+        _favoriteStoreBySource
+          ..clear()
+          ..addAll(storeBySource);
+        _favoriteModeByStore
+          ..clear()
+          ..addAll(modeByStore);
         _favoriteChannels = merged;
         _refreshFavoriteKeys();
       });
@@ -433,6 +484,7 @@ class _LiveTvScreenState extends State<LiveTvScreen>
   }
 
   void _toggleFavorite(LiveTvChannel channel) {
+    ++_favoritesMutationGeneration;
     final source = _sourceForChannel(channel);
     final favoriteKey = favoriteChannelKey(source, channel.key);
     final scopeKey = liveTvChannelScopeKey(channel);
@@ -460,6 +512,7 @@ class _LiveTvScreenState extends State<LiveTvScreen>
         favorites: List.from(_favoriteChannels),
         channelMap: channelMap,
         onReorder: (reordered) {
+          ++_favoritesMutationGeneration;
           setState(() {
             _favoriteChannels = reordered;
             _refreshFavoriteKeys();
@@ -467,6 +520,7 @@ class _LiveTvScreenState extends State<LiveTvScreen>
           _persistFavorites();
         },
         onRemove: (removed) {
+          ++_favoritesMutationGeneration;
           setState(() {
             _favoriteChannels = _favoriteChannels.where((f) => f.stableKey != removed.stableKey).toList();
             _refreshFavoriteKeys();

lib/screens/livetv/tabs/guide_tab.dart

@@ -198,9 +198,9 @@ class GuideTabState extends State<GuideTab> with MountedSetStateMixin, WidgetsBi
     switch (state) {
       case AppLifecycleState.paused:
       case AppLifecycleState.hidden:
-        _hiddenSince ??= DateTime.now();
+        pauseRefresh();
       case AppLifecycleState.resumed:
-        _catchUpIfStale();
+        if (_isGuideVisible) resumeRefresh();
       case AppLifecycleState.inactive:
       case AppLifecycleState.detached:
         break;
@@ -1103,6 +1103,7 @@ class GuideTabState extends State<GuideTab> with MountedSetStateMixin, WidgetsBi
         }),
       ],
     );
+    if (!mounted) return;
     if (value == null) {
       _guideFocusNode.requestFocus();
       return;

lib/screens/livetv/tabs/recordings_tab.dart

@@ -58,26 +58,45 @@ class _RuleEntry {
 
 enum _RuleAction { edit, delete }
 
-class RecordingsTabState extends State<RecordingsTab> {
+class RecordingsTabState extends State<RecordingsTab> with WidgetsBindingObserver {
   List<_ServerRecordings> _serverRecordings = [];
   bool _isLoading = true;
   bool _adminBlocked = false;
   String? _error;
   Timer? _refreshTimer;
   bool _pendingFocus = false;
+  bool _refreshRequested = true;
+  bool _tickerEnabled = false;
+  bool _appResumed = true;
   final _firstTileFocusNode = FocusNode(debugLabel: 'recordings_tab_first_tile');
 
   @override
   void initState() {
     super.initState();
+    WidgetsBinding.instance.addObserver(this);
     _load();
-    _refreshTimer = Timer.periodic(const Duration(seconds: 30), (_) {
+  }
-      if (mounted) _load();
+
-    });
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    final enabled = TickerMode.valuesOf(context).enabled;
+    if (enabled == _tickerEnabled) return;
+    _tickerEnabled = enabled;
+    _syncRefreshTimer();
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    final resumed = state == AppLifecycleState.resumed;
+    if (resumed == _appResumed) return;
+    _appResumed = resumed;
+    _syncRefreshTimer();
   }
 
   @override
   void dispose() {
+    WidgetsBinding.instance.removeObserver(this);
     _refreshTimer?.cancel();
     _firstTileFocusNode.dispose();
     super.dispose();
@@ -94,14 +113,22 @@ class RecordingsTabState extends State<RecordingsTab> {
     }
   }
 
-  void pauseRefresh() => _refreshTimer?.cancel();
+  void pauseRefresh() {
+    _refreshRequested = false;
+    _syncRefreshTimer();
+  }
 
   void resumeRefresh() {
+    _refreshRequested = true;
+    _syncRefreshTimer(reload: true);
+  }
+
+  void _syncRefreshTimer({bool reload = false}) {
     _refreshTimer?.cancel();
-    _refreshTimer = Timer.periodic(const Duration(seconds: 30), (_) {
+    _refreshTimer = null;
-      if (mounted) _load();
+    if (!_refreshRequested || !_tickerEnabled || !_appResumed || !mounted) return;
-    });
+    _refreshTimer = Timer.periodic(const Duration(seconds: 30), (_) => _load());
-    _load();
+    if (reload) unawaited(_load());
   }
 
   /// Public reload helper for the parent screen's refresh action.

lib/screens/livetv/tabs/whats_on_tab.dart

@@ -28,6 +28,7 @@ import '../../../widgets/overlay_sheet.dart';
 import '../../../utils/scroll_utils.dart';
 import '../../../widgets/horizontal_scroll_with_arrows.dart';
 import '../../../widgets/optimized_media_image.dart';
+import '../../../widgets/sliver_child_memo.dart';
 import '../live_tv_actions_mixin.dart';
 import '../live_tv_show_schedule_screen.dart';
 
@@ -42,11 +43,16 @@ class WhatsOnTab extends StatefulWidget {
   State<WhatsOnTab> createState() => WhatsOnTabState();
 }
 
-class WhatsOnTabState extends State<WhatsOnTab> with LiveTvActionsMixin<WhatsOnTab>, MountedSetStateMixin {
+class WhatsOnTabState extends State<WhatsOnTab>
+    with LiveTvActionsMixin<WhatsOnTab>, MountedSetStateMixin, WidgetsBindingObserver {
   List<LiveTvHubResult> _hubs = [];
   bool _isLoading = true;
   Timer? _refreshTimer;
+  final Map<String, GlobalKey<_LiveTvHubSectionState>> _hubKeysById = {};
   List<GlobalKey<_LiveTvHubSectionState>> _hubKeys = [];
+  bool _refreshRequested = true;
+  bool _tickerEnabled = false;
+  bool _appResumed = true;
 
   @override
   List<LiveTvChannel> get liveTvChannels => widget.channels;
@@ -54,23 +60,47 @@ class WhatsOnTabState extends State<WhatsOnTab> with LiveTvActionsMixin<WhatsOnT
   @override
   void initState() {
     super.initState();
+    WidgetsBinding.instance.addObserver(this);
     _loadHubs();
-    _refreshTimer = Timer.periodic(const Duration(seconds: 60), (_) {
-      if (mounted) _loadHubs();
-    });
   }
 
-  void pauseRefresh() => _refreshTimer?.cancel();
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    final enabled = TickerMode.valuesOf(context).enabled;
+    if (enabled == _tickerEnabled) return;
+    _tickerEnabled = enabled;
+    _syncRefreshTimer();
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    final resumed = state == AppLifecycleState.resumed;
+    if (resumed == _appResumed) return;
+    _appResumed = resumed;
+    _syncRefreshTimer();
+  }
+
+  void pauseRefresh() {
+    _refreshRequested = false;
+    _syncRefreshTimer();
+  }
 
   void resumeRefresh() {
+    _refreshRequested = true;
+    _syncRefreshTimer();
+  }
+
+  void _syncRefreshTimer() {
     _refreshTimer?.cancel();
-    _refreshTimer = Timer.periodic(const Duration(seconds: 60), (_) {
+    _refreshTimer = null;
-      if (mounted) _loadHubs();
+    if (!_refreshRequested || !_tickerEnabled || !_appResumed || !mounted) return;
-    });
+    _refreshTimer = Timer.periodic(const Duration(seconds: 60), (_) => _loadHubs());
   }
 
   @override
   void dispose() {
+    WidgetsBinding.instance.removeObserver(this);
     _refreshTimer?.cancel();
     super.dispose();
   }
@@ -83,6 +113,7 @@ class WhatsOnTabState extends State<WhatsOnTab> with LiveTvActionsMixin<WhatsOnT
       final multiServer = context.read<MultiServerProvider>();
       final liveTvServers = multiServer.liveTvServers;
       final allHubs = <LiveTvHubResult>[];
+      final allHubIds = <String>[];
       final queriedServers = <String>{};
 
       for (final serverInfo in liveTvServers) {
@@ -93,16 +124,23 @@ class WhatsOnTabState extends State<WhatsOnTab> with LiveTvActionsMixin<WhatsOnT
           if (client == null) continue;
 
           final hubs = await client.getLiveTvHubs();
-          allHubs.addAll(hubs);
+          for (final hub in hubs) {
+            allHubs.add(hub);
+            allHubIds.add('${serverInfo.serverId}\u0000${hub.hubKey}');
+          }
         } catch (e) {
           appLogger.e('Failed to load hubs from server ${serverInfo.serverId}', error: e);
         }
       }
 
       if (!mounted) return;
+      final hubIds = allHubIds.toSet();
+      _hubKeysById.removeWhere((id, _) => !hubIds.contains(id));
       setState(() {
         _hubs = allHubs;
-        _hubKeys = List.generate(allHubs.length, (_) => GlobalKey<_LiveTvHubSectionState>());
+        _hubKeys = [
+          for (final hubId in allHubIds) _hubKeysById.putIfAbsent(hubId, () => GlobalKey<_LiveTvHubSectionState>()),
+        ];
         _isLoading = false;
       });
     } catch (e) {
@@ -224,6 +262,7 @@ class _LiveTvHubSectionState extends State<_LiveTvHubSection> with MountedSetSta
   static const double _leadingPadding = 12.0;
 
   final _selectLongPress = DpadSelectLongPressController();
+  final SliverChildMemo<LiveTvHubEntry> _childMemo = SliverChildMemo<LiveTvHubEntry>();
 
   @override
   void initState() {
@@ -442,22 +481,27 @@ class _LiveTvHubSectionState extends State<_LiveTvHubSection> with MountedSetSta
                       itemBuilder: (context, index) {
                         final entry = widget.hub.entries[index];
                         final isItemFocused = hasFocus && index == _focusedIndex;
-
+                        return _childMemo.widgetFor(
-                        return Padding(
+                          index,
-                          padding: const EdgeInsets.symmetric(horizontal: 2),
+                          entry,
-                          child: _LiveTvPosterCard(
+                          epoch: (cardWidth, posterHeight, widget.hub.entries.length),
-                            entry: entry,
+                          salt: isItemFocused,
-                            width: cardWidth,
+                          build: () => Padding(
-                            posterHeight: posterHeight,
+                            padding: const EdgeInsets.symmetric(horizontal: 2),
-                            isFocused: isItemFocused,
+                            child: _LiveTvPosterCard(
-                            onTap: () {
+                              entry: entry,
-                              _onItemTapped(index);
+                              width: cardWidth,
-                              widget.onTap(entry);
+                              posterHeight: posterHeight,
-                            },
+                              isFocused: isItemFocused,
-                            onLongPress: () {
+                              onTap: () {
-                              _onItemTapped(index);
+                                _onItemTapped(index);
-                              widget.onLongPress(entry);
+                                widget.onTap(entry);
-                            },
+                              },
+                              onLongPress: () {
+                                _onItemTapped(index);
+                                widget.onLongPress(entry);
+                              },
+                            ),
                           ),
                         );
                       },