Cache messages, use cache if exists, load in background

flutter/Makefile

@@ -1,7 +1,7 @@
 
 
 run:
-	dart run build_runner build
+	flutter pub run build_runner build
 	flutter run
 	
 test:
@@ -11,7 +11,7 @@ fix:
 	dart fix --apply
 
 gen:
-	dart run build_runner build
+	flutter pub run build_runner build
 	
 autoreload:
 	@# run `make run` in another terminal (or another variant of flutter run)

flutter/lib/components/layout/app_bar.dart

@@ -1,4 +1,5 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
 import 'package:font_awesome_flutter/font_awesome_flutter.dart';
 import 'package:provider/provider.dart';
 import 'package:simplecloudnotifier/components/layout/app_bar_progress_indicator.dart';
@@ -28,6 +29,16 @@ class SCNAppBar extends StatelessWidget implements PreferredSizeWidget {
   Widget build(BuildContext context) {
     var actions = <Widget>[];
 
+    if (showDebug) {
+      actions.add(IconButton(
+        icon: const Icon(FontAwesomeIcons.solidSpiderBlackWidow),
+        tooltip: 'Debug',
+        onPressed: () {
+          Navi.push(context, () => DebugMainPage());
+        },
+      ));
+    }
+
     if (showThemeSwitch) {
       actions.add(Consumer<AppTheme>(
         builder: (context, appTheme, child) => IconButton(
@@ -37,19 +48,16 @@ class SCNAppBar extends StatelessWidget implements PreferredSizeWidget {
         ),
       ));
     } else {
-      actions.add(SizedBox.square(dimension: 40));
+      actions.add(Visibility(
-    }
+        visible: false,
-
+        maintainSize: true,
-    if (showDebug) {
+        maintainAnimation: true,
-      actions.add(IconButton(
+        maintainState: true,
-        icon: const Icon(FontAwesomeIcons.solidSpiderBlackWidow),
+        child: IconButton(
-        tooltip: 'Debug',
+          icon: const Icon(FontAwesomeIcons.square),
-        onPressed: () {
+          onPressed: () {/*TODO*/},
-          Navi.push(context, () => DebugMainPage());
+        ),
-        },
       ));
-    } else {
-      actions.add(SizedBox.square(dimension: 40));
     }
 
     if (showSearch) {
@@ -65,7 +73,16 @@ class SCNAppBar extends StatelessWidget implements PreferredSizeWidget {
         onPressed: onShare ?? () {},
       ));
     } else {
-      actions.add(SizedBox.square(dimension: 40));
+      actions.add(Visibility(
+        visible: false,
+        maintainSize: true,
+        maintainAnimation: true,
+        maintainState: true,
+        child: IconButton(
+          icon: const Icon(FontAwesomeIcons.square),
+          onPressed: () {/*TODO*/},
+        ),
+      ));
     }
 
     return AppBar(

flutter/lib/main.dart

@@ -5,7 +5,9 @@ import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 import 'package:hive_flutter/hive_flutter.dart';
 import 'package:simplecloudnotifier/api/api_client.dart';
+import 'package:simplecloudnotifier/models/channel.dart';
 import 'package:simplecloudnotifier/models/client.dart';
+import 'package:simplecloudnotifier/models/message.dart';
 import 'package:simplecloudnotifier/nav_layout.dart';
 import 'package:simplecloudnotifier/state/app_bar_state.dart';
 import 'package:simplecloudnotifier/state/app_theme.dart';
@@ -36,6 +38,8 @@ void main() async {
   Hive.registerAdapter(SCNRequestAdapter());
   Hive.registerAdapter(SCNLogAdapter());
   Hive.registerAdapter(SCNLogLevelAdapter());
+  Hive.registerAdapter(MessageAdapter());
+  Hive.registerAdapter(ChannelAdapter());
 
   print('[INIT] Load Hive<scn-requests>...');
 
@@ -57,6 +61,26 @@ void main() async {
     ApplicationLog.error('Failed to open Hive-Box: scn-logs: ' + exc.toString(), trace: trace);
   }
 
+  print('[INIT] Load Hive<scn-message-cache>...');
+
+  try {
+    await Hive.openBox<Message>('scn-message-cache');
+  } catch (exc, trace) {
+    Hive.deleteBoxFromDisk('scn-message-cache');
+    await Hive.openBox<Message>('scn-message-cache');
+    ApplicationLog.error('Failed to open Hive-Box: scn-message-cache' + exc.toString(), trace: trace);
+  }
+
+  print('[INIT] Load Hive<scn-channel-cache>...');
+
+  try {
+    await Hive.openBox<Channel>('scn-channel-cache');
+  } catch (exc, trace) {
+    Hive.deleteBoxFromDisk('scn-channel-cache');
+    await Hive.openBox<Channel>('scn-channel-cache');
+    ApplicationLog.error('Failed to open Hive-Box: scn-channel-cache' + exc.toString(), trace: trace);
+  }
+
   print('[INIT] Load AppAuth...');
 
   final appAuth = AppAuth(); // ensure UserAccount is loaded
@@ -135,7 +159,7 @@ void setFirebaseToken(String fcmToken) async {
 
   Client? client;
   try {
-    client = await acc.loadClient(force: true);
+    client = await acc.loadClient(forceIfOlder: Duration(seconds: 60));
   } catch (exc, trace) {
     ApplicationLog.error('Failed to get client: ' + exc.toString(), trace: trace);
     return;
@@ -172,7 +196,7 @@ class SCNApp extends StatelessWidget {
       child: Consumer<AppTheme>(
         builder: (context, appTheme, child) => MaterialApp(
           title: 'SimpleCloudNotifier',
-          navigatorObservers: [Navi.routeObserver],
+          navigatorObservers: [Navi.routeObserver, Navi.modalRouteObserver],
           theme: ThemeData(
             //TODO color settings
             colorScheme: ColorScheme.fromSeed(seedColor: Colors.blue, brightness: appTheme.darkMode ? Brightness.dark : Brightness.light),

flutter/lib/models/channel.dart

@@ -1,17 +1,32 @@
+import 'package:hive_flutter/hive_flutter.dart';
 import 'package:simplecloudnotifier/models/subscription.dart';
+import 'package:simplecloudnotifier/state/interfaces.dart';
 
-class Channel {
+part 'channel.g.dart';
+
+@HiveType(typeId: 104)
+class Channel extends HiveObject implements FieldDebuggable {
+  @HiveField(0)
   final String channelID;
+
+  @HiveField(10)
   final String ownerUserID;
+  @HiveField(11)
   final String internalName;
+  @HiveField(12)
   final String displayName;
+  @HiveField(13)
   final String? descriptionName;
+  @HiveField(14)
   final String? subscribeKey;
+  @HiveField(15)
   final String timestampCreated;
+  @HiveField(16)
   final String? timestampLastSent;
+  @HiveField(17)
   final int messagesSent;
 
-  const Channel({
+  Channel({
     required this.channelID,
     required this.ownerUserID,
     required this.internalName,
@@ -36,6 +51,25 @@ class Channel {
       messagesSent: json['messages_sent'] as int,
     );
   }
+
+  @override
+  String toString() {
+    return 'Channel[${this.channelID}]';
+  }
+
+  List<(String, String)> debugFieldList() {
+    return [
+      ('channelID', this.channelID),
+      ('ownerUserID', this.ownerUserID),
+      ('internalName', this.internalName),
+      ('displayName', this.displayName),
+      ('descriptionName', this.descriptionName ?? ''),
+      ('subscribeKey', this.subscribeKey ?? ''),
+      ('timestampCreated', this.timestampCreated),
+      ('timestampLastSent', this.timestampLastSent ?? ''),
+      ('messagesSent', '${this.messagesSent}'),
+    ];
+  }
 }
 
 class ChannelWithSubscription {

flutter/lib/models/channel.g.dart

@@ -0,0 +1,65 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'channel.dart';
+
+// **************************************************************************
+// TypeAdapterGenerator
+// **************************************************************************
+
+class ChannelAdapter extends TypeAdapter<Channel> {
+  @override
+  final int typeId = 104;
+
+  @override
+  Channel read(BinaryReader reader) {
+    final numOfFields = reader.readByte();
+    final fields = <int, dynamic>{
+      for (int i = 0; i < numOfFields; i++) reader.readByte(): reader.read(),
+    };
+    return Channel(
+      channelID: fields[0] as String,
+      ownerUserID: fields[10] as String,
+      internalName: fields[11] as String,
+      displayName: fields[12] as String,
+      descriptionName: fields[13] as String?,
+      subscribeKey: fields[14] as String?,
+      timestampCreated: fields[15] as String,
+      timestampLastSent: fields[16] as String?,
+      messagesSent: fields[17] as int,
+    );
+  }
+
+  @override
+  void write(BinaryWriter writer, Channel obj) {
+    writer
+      ..writeByte(9)
+      ..writeByte(0)
+      ..write(obj.channelID)
+      ..writeByte(10)
+      ..write(obj.ownerUserID)
+      ..writeByte(11)
+      ..write(obj.internalName)
+      ..writeByte(12)
+      ..write(obj.displayName)
+      ..writeByte(13)
+      ..write(obj.descriptionName)
+      ..writeByte(14)
+      ..write(obj.subscribeKey)
+      ..writeByte(15)
+      ..write(obj.timestampCreated)
+      ..writeByte(16)
+      ..write(obj.timestampLastSent)
+      ..writeByte(17)
+      ..write(obj.messagesSent);
+  }
+
+  @override
+  int get hashCode => typeId.hashCode;
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is ChannelAdapter &&
+          runtimeType == other.runtimeType &&
+          typeId == other.typeId;
+}

flutter/lib/models/message.dart

@@ -1,19 +1,39 @@
-class Message {
+import 'package:hive_flutter/hive_flutter.dart';
+import 'package:simplecloudnotifier/state/interfaces.dart';
+
+part 'message.g.dart';
+
+@HiveType(typeId: 105)
+class Message extends HiveObject implements FieldDebuggable {
+  @HiveField(0)
   final String messageID;
+
+  @HiveField(10)
   final String senderUserID;
+  @HiveField(11)
   final String channelInternalName;
+  @HiveField(12)
   final String channelID;
+  @HiveField(13)
   final String? senderName;
+  @HiveField(14)
   final String senderIP;
+  @HiveField(15)
   final String timestamp;
+  @HiveField(16)
   final String title;
+  @HiveField(17)
   final String? content;
+  @HiveField(18)
   final int priority;
+  @HiveField(19)
   final String? userMessageID;
+  @HiveField(20)
   final String usedKeyID;
+  @HiveField(21)
   final bool trimmed;
 
-  const Message({
+  Message({
     required this.messageID,
     required this.senderUserID,
     required this.channelInternalName,
@@ -54,4 +74,27 @@ class Message {
 
     return (npt, messages);
   }
+
+  @override
+  String toString() {
+    return 'Message[${this.messageID}]';
+  }
+
+  List<(String, String)> debugFieldList() {
+    return [
+      ('messageID', this.messageID),
+      ('senderUserID', this.senderUserID),
+      ('channelInternalName', this.channelInternalName),
+      ('channelID', this.channelID),
+      ('senderName', this.senderName ?? ''),
+      ('senderIP', this.senderIP),
+      ('timestamp', this.timestamp),
+      ('title', this.title),
+      ('content', this.content ?? ''),
+      ('priority', '${this.priority}'),
+      ('userMessageID', this.userMessageID ?? ''),
+      ('usedKeyID', this.usedKeyID),
+      ('trimmed', '${this.trimmed}'),
+    ];
+  }
 }

flutter/lib/models/message.g.dart

@@ -0,0 +1,77 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'message.dart';
+
+// **************************************************************************
+// TypeAdapterGenerator
+// **************************************************************************
+
+class MessageAdapter extends TypeAdapter<Message> {
+  @override
+  final int typeId = 105;
+
+  @override
+  Message read(BinaryReader reader) {
+    final numOfFields = reader.readByte();
+    final fields = <int, dynamic>{
+      for (int i = 0; i < numOfFields; i++) reader.readByte(): reader.read(),
+    };
+    return Message(
+      messageID: fields[0] as String,
+      senderUserID: fields[10] as String,
+      channelInternalName: fields[11] as String,
+      channelID: fields[12] as String,
+      senderName: fields[13] as String?,
+      senderIP: fields[14] as String,
+      timestamp: fields[15] as String,
+      title: fields[16] as String,
+      content: fields[17] as String?,
+      priority: fields[18] as int,
+      userMessageID: fields[19] as String?,
+      usedKeyID: fields[20] as String,
+      trimmed: fields[21] as bool,
+    );
+  }
+
+  @override
+  void write(BinaryWriter writer, Message obj) {
+    writer
+      ..writeByte(13)
+      ..writeByte(0)
+      ..write(obj.messageID)
+      ..writeByte(10)
+      ..write(obj.senderUserID)
+      ..writeByte(11)
+      ..write(obj.channelInternalName)
+      ..writeByte(12)
+      ..write(obj.channelID)
+      ..writeByte(13)
+      ..write(obj.senderName)
+      ..writeByte(14)
+      ..write(obj.senderIP)
+      ..writeByte(15)
+      ..write(obj.timestamp)
+      ..writeByte(16)
+      ..write(obj.title)
+      ..writeByte(17)
+      ..write(obj.content)
+      ..writeByte(18)
+      ..write(obj.priority)
+      ..writeByte(19)
+      ..write(obj.userMessageID)
+      ..writeByte(20)
+      ..write(obj.usedKeyID)
+      ..writeByte(21)
+      ..write(obj.trimmed);
+  }
+
+  @override
+  int get hashCode => typeId.hashCode;
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is MessageAdapter &&
+          runtimeType == other.runtimeType &&
+          typeId == other.typeId;
+}

flutter/lib/nav_layout.dart

@@ -66,11 +66,11 @@ class _SCNNavLayoutState extends State<SCNNavLayout> {
       ),
       body: IndexedStack(
         children: [
-          ExcludeFocus(excluding: _selectedIndex != 0, child: MessageListPage()),
+          ExcludeFocus(excluding: _selectedIndex != 0, child: MessageListPage(isVisiblePage: _selectedIndex == 0)),
-          ExcludeFocus(excluding: _selectedIndex != 1, child: ChannelRootPage()),
+          ExcludeFocus(excluding: _selectedIndex != 1, child: ChannelRootPage(isVisiblePage: _selectedIndex == 1)),
-          ExcludeFocus(excluding: _selectedIndex != 2, child: AccountRootPage()),
+          ExcludeFocus(excluding: _selectedIndex != 2, child: AccountRootPage(isVisiblePage: _selectedIndex == 2)),
-          ExcludeFocus(excluding: _selectedIndex != 3, child: SettingsRootPage()),
+          ExcludeFocus(excluding: _selectedIndex != 3, child: SettingsRootPage(isVisiblePage: _selectedIndex == 3)),
-          ExcludeFocus(excluding: _selectedIndex != 4, child: SendRootPage()),
+          ExcludeFocus(excluding: _selectedIndex != 4, child: SendRootPage(isVisiblePage: _selectedIndex == 4)),
         ],
         index: _selectedIndex,
       ),

flutter/lib/pages/account/account.dart

@@ -16,7 +16,9 @@ import 'package:simplecloudnotifier/utils/ui.dart';
 import 'package:uuid/uuid.dart';
 
 class AccountRootPage extends StatefulWidget {
-  const AccountRootPage({super.key});
+  const AccountRootPage({super.key, required this.isVisiblePage});
+
+  final bool isVisiblePage;
 
   @override
   State<AccountRootPage> createState() => _AccountRootPageState();
@@ -33,13 +35,34 @@ class _AccountRootPageState extends State<AccountRootPage> {
 
   bool loading = false;
 
+  bool _isInitialized = false;
+
   @override
   void initState() {
     super.initState();
 
     userAcc = Provider.of<AppAuth>(context, listen: false);
     userAcc.addListener(_onAuthStateChanged);
+
+    if (widget.isVisiblePage && !_isInitialized) realInitState();
+  }
+
+  @override
+  void didUpdateWidget(AccountRootPage oldWidget) {
+    super.didUpdateWidget(oldWidget);
+
+    if (oldWidget.isVisiblePage != widget.isVisiblePage && widget.isVisiblePage) {
+      if (!_isInitialized) {
+        realInitState();
+      } else {
+        //TODO background refresh
+      }
+    }
+  }
+
+  void realInitState() {
     _onAuthStateChanged();
+    _isInitialized = true;
   }
 
   @override
@@ -92,6 +115,8 @@ class _AccountRootPageState extends State<AccountRootPage> {
   Widget build(BuildContext context) {
     return Consumer<AppAuth>(
       builder: (context, acc, child) {
+        if (!_isInitialized) return SizedBox();
+
         if (!userAcc.isAuth()) {
           return _buildNoAuth(context);
         } else {

flutter/lib/pages/channel_list/channel_list.dart

@@ -8,21 +8,26 @@ import 'package:simplecloudnotifier/state/app_auth.dart';
 import 'package:simplecloudnotifier/pages/channel_list/channel_list_item.dart';
 
 class ChannelRootPage extends StatefulWidget {
-  const ChannelRootPage({super.key});
+  const ChannelRootPage({super.key, required this.isVisiblePage});
+
+  final bool isVisiblePage;
 
   @override
   State<ChannelRootPage> createState() => _ChannelRootPageState();
 }
 
 class _ChannelRootPageState extends State<ChannelRootPage> {
-  final PagingController<int, Channel> _pagingController = PagingController(firstPageKey: 0);
+  final PagingController<int, Channel> _pagingController = PagingController.fromValue(PagingState(nextPageKey: null, itemList: [], error: null), firstPageKey: 0);
+
+  bool _isInitialized = false;
 
   @override
   void initState() {
-    _pagingController.addPageRequestListener((pageKey) {
-      _fetchPage(pageKey);
-    });
     super.initState();
+
+    _pagingController.addPageRequestListener(_fetchPage);
+
+    if (widget.isVisiblePage && !_isInitialized) realInitState();
   }
 
   @override
@@ -31,9 +36,29 @@ class _ChannelRootPageState extends State<ChannelRootPage> {
     super.dispose();
   }
 
+  @override
+  void didUpdateWidget(ChannelRootPage oldWidget) {
+    super.didUpdateWidget(oldWidget);
+
+    if (oldWidget.isVisiblePage != widget.isVisiblePage && widget.isVisiblePage) {
+      if (!_isInitialized) {
+        realInitState();
+      } else {
+        //TODO background refresh
+      }
+    }
+  }
+
+  void realInitState() {
+    _pagingController.refresh();
+    _isInitialized = true;
+  }
+
   Future<void> _fetchPage(int pageKey) async {
     final acc = Provider.of<AppAuth>(context, listen: false);
 
+    ApplicationLog.debug('Start ChannelList::_pagingController::_fetchPage [ ${pageKey} ]');
+
     if (!acc.isAuth()) {
       _pagingController.error = 'Not logged in';
       return;

flutter/lib/pages/debug/debug_persistence.dart

@@ -1,6 +1,8 @@
 import 'package:flutter/material.dart';
 import 'package:hive_flutter/hive_flutter.dart';
 import 'package:shared_preferences/shared_preferences.dart';
+import 'package:simplecloudnotifier/models/channel.dart';
+import 'package:simplecloudnotifier/models/message.dart';
 import 'package:simplecloudnotifier/pages/debug/debug_persistence_hive.dart';
 import 'package:simplecloudnotifier/pages/debug/debug_persistence_sharedprefs.dart';
 import 'package:simplecloudnotifier/state/application_log.dart';
@@ -83,6 +85,42 @@ class _DebugPersistencePageState extends State<DebugPersistencePage> {
               ),
             ),
           ),
+          Card.outlined(
+            child: Padding(
+              padding: const EdgeInsets.all(8.0),
+              child: GestureDetector(
+                onTap: () {
+                  Navi.push(context, () => DebugHiveBoxPage(boxName: 'scn-message-cache', box: Hive.box<Message>('scn-message-cache')));
+                },
+                child: Row(
+                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                  children: [
+                    SizedBox(width: 30, child: Text('')),
+                    Expanded(child: Text('Hive [scn-message-cache]', style: TextStyle(fontWeight: FontWeight.bold), textAlign: TextAlign.center)),
+                    SizedBox(width: 30, child: Text('${Hive.box<Message>('scn-message-cache').length.toString()}', textAlign: TextAlign.end)),
+                  ],
+                ),
+              ),
+            ),
+          ),
+          Card.outlined(
+            child: Padding(
+              padding: const EdgeInsets.all(8.0),
+              child: GestureDetector(
+                onTap: () {
+                  Navi.push(context, () => DebugHiveBoxPage(boxName: 'scn-channel-cache', box: Hive.box<Channel>('scn-channel-cache')));
+                },
+                child: Row(
+                  mainAxisAlignment: MainAxisAlignment.spaceBetween,
+                  children: [
+                    SizedBox(width: 30, child: Text('')),
+                    Expanded(child: Text('Hive [scn-channel-cache]', style: TextStyle(fontWeight: FontWeight.bold), textAlign: TextAlign.center)),
+                    SizedBox(width: 30, child: Text('${Hive.box<Channel>('scn-channel-cache').length.toString()}', textAlign: TextAlign.end)),
+                  ],
+                ),
+              ),
+            ),
+          ),
         ],
       ),
     );

flutter/lib/pages/message_list/message_list.dart

@@ -1,17 +1,21 @@
 import 'package:flutter/material.dart';
+import 'package:hive_flutter/hive_flutter.dart';
 import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
 import 'package:provider/provider.dart';
 import 'package:simplecloudnotifier/api/api_client.dart';
 import 'package:simplecloudnotifier/models/channel.dart';
 import 'package:simplecloudnotifier/models/message.dart';
 import 'package:simplecloudnotifier/pages/message_view/message_view.dart';
+import 'package:simplecloudnotifier/state/app_bar_state.dart';
 import 'package:simplecloudnotifier/state/application_log.dart';
 import 'package:simplecloudnotifier/state/app_auth.dart';
 import 'package:simplecloudnotifier/pages/message_list/message_list_item.dart';
 import 'package:simplecloudnotifier/utils/navi.dart';
 
 class MessageListPage extends StatefulWidget {
-  const MessageListPage({super.key});
+  const MessageListPage({super.key, required this.isVisiblePage});
+
+  final bool isVisiblePage;
 
   //TODO reload on switch to tab
   //TODO reload on app to foreground
@@ -20,31 +24,90 @@ class MessageListPage extends StatefulWidget {
   State<MessageListPage> createState() => _MessageListPageState();
 }
 
-class _MessageListPageState extends State<MessageListPage> {
+class _MessageListPageState extends State<MessageListPage> with RouteAware {
   static const _pageSize = 128;
 
-  final PagingController<String, Message> _pagingController = PagingController(firstPageKey: '@start');
+  PagingController<String, Message> _pagingController = PagingController.fromValue(PagingState(nextPageKey: null, itemList: [], error: null), firstPageKey: '@start');
 
   Map<String, Channel>? _channels = null;
 
+  bool _isInitialized = false;
+
   @override
   void initState() {
-    //TODO init with state from cache - also allow tho show cache on error
-    _pagingController.addPageRequestListener((pageKey) {
-      _fetchPage(pageKey);
-    });
     super.initState();
+
+    _pagingController.addPageRequestListener(_fetchPage);
+
+    if (widget.isVisiblePage && !_isInitialized) realInitState();
+  }
+
+  @override
+  void didUpdateWidget(MessageListPage oldWidget) {
+    super.didUpdateWidget(oldWidget);
+
+    if (oldWidget.isVisiblePage != widget.isVisiblePage && widget.isVisiblePage) {
+      if (!_isInitialized) {
+        realInitState();
+      } else {
+        _backgroundRefresh(false);
+      }
+    }
+  }
+
+  void realInitState() {
+    final chnCache = Hive.box<Channel>('scn-channel-cache');
+    final msgCache = Hive.box<Message>('scn-message-cache');
+
+    if (chnCache.isNotEmpty && msgCache.isNotEmpty) {
+      // ==== Use cache values - and refresh in background
+
+      _channels = <String, Channel>{for (var v in chnCache.values) v.channelID: v};
+
+      final cacheMessages = msgCache.values.toList();
+      cacheMessages.sort((a, b) => -1 * a.timestamp.compareTo(b.timestamp));
+
+      _pagingController.value = PagingState(nextPageKey: null, itemList: cacheMessages, error: null);
+
+      _backgroundRefresh(true);
+    } else {
+      // ==== Full refresh - no cache available
+      _pagingController.refresh();
+    }
+
+    _isInitialized = true;
+  }
+
+  @override
+  void didChangeDependencies() {
+    super.didChangeDependencies();
+    Navi.modalRouteObserver.subscribe(this, ModalRoute.of(context)!);
   }
 
   @override
   void dispose() {
+    Navi.modalRouteObserver.unsubscribe(this);
     _pagingController.dispose();
     super.dispose();
   }
 
+  @override
+  void didPush() {
+    // Route was pushed onto navigator and is now the topmost route.
+    ApplicationLog.debug('[MessageList::RouteObserver] --> didPush');
+  }
+
+  @override
+  void didPopNext() {
+    // Covering route was popped off the navigator.
+    ApplicationLog.debug('[MessageList::RouteObserver] --> didPopNext');
+  }
+
   Future<void> _fetchPage(String thisPageToken) async {
     final acc = Provider.of<AppAuth>(context, listen: false);
 
+    ApplicationLog.debug('Start MessageList::_pagingController::_fetchPage [ ${thisPageToken} ]');
+
     if (!acc.isAuth()) {
       _pagingController.error = 'Not logged in';
       return;
@@ -54,10 +117,16 @@ class _MessageListPageState extends State<MessageListPage> {
       if (_channels == null) {
         final channels = await APIClient.getChannelList(acc, ChannelSelector.allAny);
         _channels = <String, Channel>{for (var v in channels) v.channel.channelID: v.channel};
+
+        _setChannelCache(channels); // no await
       }
 
       final (npt, newItems) = await APIClient.getMessageList(acc, thisPageToken, pageSize: _pageSize);
 
+      _addToMessageCache(newItems); // no await
+
+      ApplicationLog.debug('Finished MessageList::_pagingController::_fetchPage [ ${newItems.length} items and npt: ${thisPageToken} --> ${npt} ]');
+
       if (npt == '@end') {
         _pagingController.appendLastPage(newItems);
       } else {
@@ -69,6 +138,71 @@ class _MessageListPageState extends State<MessageListPage> {
     }
   }
 
+  Future<void> _backgroundRefresh(bool fullReplaceState) async {
+    final acc = Provider.of<AppAuth>(context, listen: false);
+
+    ApplicationLog.debug('Start background refresh of message list (fullReplaceState: $fullReplaceState)');
+
+    try {
+      await Future.delayed(const Duration(seconds: 0), () {}); // this is annoyingly important - otherwise we call setLoadingIndeterminate directly in initStat() and get an exception....
+
+      AppBarState().setLoadingIndeterminate(true);
+
+      if (_channels == null || fullReplaceState) {
+        final channels = await APIClient.getChannelList(acc, ChannelSelector.allAny);
+        setState(() {
+          _channels = <String, Channel>{for (var v in channels) v.channel.channelID: v.channel};
+        });
+        _setChannelCache(channels); // no await
+      }
+
+      final (npt, newItems) = await APIClient.getMessageList(acc, '@start', pageSize: _pageSize);
+
+      _addToMessageCache(newItems); // no await
+
+      if (fullReplaceState) {
+        // fully replace/reset state
+        ApplicationLog.debug('Background-refresh finished (fullReplaceState) - replace state with ${newItems.length} items and npt: [ $npt ]');
+        setState(() {
+          if (npt == '@end')
+            _pagingController.value = PagingState(nextPageKey: null, itemList: newItems, error: null);
+          else
+            _pagingController.value = PagingState(nextPageKey: npt, itemList: newItems, error: null);
+        });
+      } else {
+        final itemsToBeAdded = newItems.where((p1) => !(_pagingController.itemList ?? []).any((p2) => p1.messageID == p2.messageID)).toList();
+        if (itemsToBeAdded.isEmpty) {
+          // nothing to do - no new items...
+          // ....
+          ApplicationLog.debug('Background-refresh returned no new items - nothing to do.');
+        } else if (itemsToBeAdded.length == newItems.length) {
+          // all items are new ?!?, the current state is completely fucked - full replace
+          ApplicationLog.debug('Background-refresh found only new items ?!? - fully replace state with ${newItems.length} items');
+          setState(() {
+            if (npt == '@end')
+              _pagingController.value = PagingState(nextPageKey: null, itemList: newItems, error: null);
+            else
+              _pagingController.value = PagingState(nextPageKey: npt, itemList: newItems, error: null);
+            _pagingController.itemList = null;
+          });
+        } else {
+          // add new items to the front
+          ApplicationLog.debug('Background-refresh found ${newItems.length} new items - add to front');
+          setState(() {
+            _pagingController.itemList = itemsToBeAdded + (_pagingController.itemList ?? []);
+          });
+        }
+      }
+    } catch (exc, trace) {
+      setState(() {
+        _pagingController.error = exc.toString();
+      });
+      ApplicationLog.error('Failed to list messages: ' + exc.toString(), trace: trace);
+    } finally {
+      AppBarState().setLoadingIndeterminate(false);
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return Padding(
@@ -92,4 +226,30 @@ class _MessageListPageState extends State<MessageListPage> {
       ),
     );
   }
+
+  Future<void> _setChannelCache(List<ChannelWithSubscription> channels) async {
+    final cache = Hive.box<Channel>('scn-channel-cache');
+
+    if (cache.length != channels.length) await cache.clear();
+
+    for (var chn in channels) await cache.put(chn.channel.channelID, chn.channel);
+  }
+
+  Future<void> _addToMessageCache(List<Message> newItems) async {
+    final cache = Hive.box<Message>('scn-message-cache');
+
+    for (var msg in newItems) await cache.put(msg.messageID, msg);
+
+    // delete all but the newest 128 messages
+
+    if (cache.length < _pageSize) return;
+
+    final allValues = cache.values.toList();
+
+    allValues.sort((a, b) => -1 * a.timestamp.compareTo(b.timestamp));
+
+    for (var val in allValues.sublist(_pageSize)) {
+      await cache.delete(val.messageID);
+    }
+  }
 }

flutter/lib/pages/send/send.dart

@@ -6,7 +6,7 @@ import 'package:url_launcher/url_launcher.dart';
 import 'package:simplecloudnotifier/state/app_auth.dart';
 
 class SendRootPage extends StatefulWidget {
-  const SendRootPage({super.key});
+  const SendRootPage({super.key, required bool isVisiblePage});
 
   @override
   State<SendRootPage> createState() => _SendRootPageState();

flutter/lib/pages/settings/root.dart

@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 
 class SettingsRootPage extends StatefulWidget {
-  const SettingsRootPage({super.key});
+  const SettingsRootPage({super.key, required bool isVisiblePage});
 
   @override
   State<SettingsRootPage> createState() => _SettingsRootPageState();

flutter/lib/state/app_auth.dart

@@ -14,6 +14,7 @@ class AppAuth extends ChangeNotifier implements TokenSource {
 
   User? _user;
   Client? _client;
+  DateTime? _clientQueryTime;
 
   String? get userID => _userID;
   String? get tokenAdmin => _tokenAdmin;
@@ -124,7 +125,11 @@ class AppAuth extends ChangeNotifier implements TokenSource {
     return user;
   }
 
-  Future<Client?> loadClient({bool force = false}) async {
+  Future<Client?> loadClient({bool force = false, Duration? forceIfOlder = null}) async {
+    if (forceIfOlder != null && _clientQueryTime != null && _clientQueryTime!.difference(DateTime.now()) > forceIfOlder) {
+      force = true;
+    }
+
     if (!force && _client != null && _client!.clientID == _clientID) {
       return _client!;
     }

flutter/lib/utils/navi.dart

@@ -4,6 +4,7 @@ import 'package:simplecloudnotifier/state/app_bar_state.dart';
 
 class Navi {
   static final SCNRouteObserver routeObserver = SCNRouteObserver();
+  static final RouteObserver<ModalRoute<void>> modalRouteObserver = RouteObserver<ModalRoute<void>>();
 
   static void push<T extends Widget>(BuildContext context, T Function() builder) {
     Provider.of<AppBarState>(context, listen: false).setLoadingIndeterminate(false);