feat: add the function to hide records that are only valid for time.

lib/models/train_record.dart

@@ -149,7 +149,7 @@ class TrainRecord {
     final lbjClassValue = lbjClass.trim();
     final trainValue = train.trim();
 
-    if (trainValue == "<NUL>") {
+    if (trainValue == "<NUL>" || trainValue.contains("-----")) {
       return "";
     }
 

lib/screens/history_screen.dart

@@ -1,8 +1,12 @@
 import 'dart:math' as math;
 import 'dart:isolate';
+import 'dart:async';
+import 'dart:convert';
 import 'package:flutter/material.dart';
+import 'package:flutter/scheduler.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:latlong2/latlong.dart';
+import 'package:scrollview_observer/scrollview_observer.dart';
 import '../models/merged_record.dart';
 import '../services/database_service.dart';
 import '../models/train_record.dart';
@@ -31,6 +35,9 @@ class HistoryScreenState extends State<HistoryScreen> {
   final Set<String> _selectedRecords = {};
   final Map<String, bool> _expandedStates = {};
   final ScrollController _scrollController = ScrollController();
+  final ListObserverController _observerController =
+      ListObserverController(controller: null)..cacheJumpIndexOffset = false;
+  late final ChatScrollObserver _chatObserver;
   bool _isAtTop = true;
   MergeSettings _mergeSettings = MergeSettings();
   double _itemHeightCache = 0.0;
@@ -53,9 +60,17 @@ class HistoryScreenState extends State<HistoryScreen> {
     });
   }
 
+  Future<void> reloadRecords() async {
+    await loadRecords(scrollToTop: false);
+  }
+
   @override
   void initState() {
     super.initState();
+    _chatObserver = ChatScrollObserver(_observerController)
+      ..toRebuildScrollViewCallback = () {
+        setState(() {});
+      };
     _scrollController.addListener(() {
       if (_scrollController.position.atEdge) {
         if (_scrollController.position.pixels == 0) {
@@ -73,6 +88,7 @@ class HistoryScreenState extends State<HistoryScreen> {
   @override
   void dispose() {
     _scrollController.dispose();
+    _observerController.controller?.dispose();
     super.dispose();
   }
 
@@ -81,7 +97,71 @@ class HistoryScreenState extends State<HistoryScreen> {
       final allRecords = await DatabaseService.instance.getAllRecords();
       final settingsMap = await DatabaseService.instance.getAllSettings() ?? {};
       _mergeSettings = MergeSettings.fromMap(settingsMap);
-      final items = MergeService.getMixedList(allRecords, _mergeSettings);
+
+      List<TrainRecord> filteredRecords = allRecords;
+      if ((settingsMap['hideTimeOnlyRecords'] ?? 0) == 1) {
+        int hiddenCount = 0;
+        int shownCount = 0;
+
+        filteredRecords = allRecords.where((record) {
+          bool isFieldMeaningful(String field) {
+            if (field.isEmpty) return false;
+            String cleaned = field.replaceAll('<NUL>', '').trim();
+            if (cleaned.isEmpty) return false;
+            if (cleaned.runes
+                .every((r) => r == '*'.runes.first || r == ' '.runes.first))
+              return false;
+            return true;
+          }
+
+          final hasTrainNumber = isFieldMeaningful(record.fullTrainNumber) &&
+              !record.fullTrainNumber.contains("-----");
+
+          final hasDirection = record.direction == 1 || record.direction == 3;
+
+          final hasLocoInfo = isFieldMeaningful(record.locoType) ||
+              isFieldMeaningful(record.loco);
+
+          final hasRoute = isFieldMeaningful(record.route);
+
+          final hasPosition = isFieldMeaningful(record.position);
+
+          final hasSpeed =
+              isFieldMeaningful(record.speed) && record.speed != "NUL";
+
+          final hasPositionInfo = isFieldMeaningful(record.positionInfo);
+
+          final hasTrainType =
+              isFieldMeaningful(record.trainType) && record.trainType != "未知";
+
+          final hasLbjClass =
+              isFieldMeaningful(record.lbjClass) && record.lbjClass != "NA";
+
+          final hasTrain = isFieldMeaningful(record.train) &&
+              !record.train.contains("-----");
+
+          final shouldShow = hasTrainNumber ||
+              hasDirection ||
+              hasLocoInfo ||
+              hasRoute ||
+              hasPosition ||
+              hasSpeed ||
+              hasPositionInfo ||
+              hasTrainType ||
+              hasLbjClass ||
+              hasTrain;
+
+          if (!shouldShow) {
+            hiddenCount++;
+          } else {
+            shownCount++;
+          }
+
+          return shouldShow;
+        }).toList();
+      }
+
+      final items = MergeService.getMixedList(filteredRecords, _mergeSettings);
 
       if (mounted) {
         final hasDataChanged = _hasDataChanged(items);
@@ -112,6 +192,58 @@ class HistoryScreenState extends State<HistoryScreen> {
       final settingsMap = await DatabaseService.instance.getAllSettings() ?? {};
       _mergeSettings = MergeSettings.fromMap(settingsMap);
 
+      if ((settingsMap['hideTimeOnlyRecords'] ?? 0) == 1) {
+        bool isFieldMeaningful(String field) {
+          if (field.isEmpty) return false;
+          String cleaned = field.replaceAll('<NUL>', '').trim();
+          if (cleaned.isEmpty) return false;
+          if (cleaned.runes
+              .every((r) => r == '*'.runes.first || r == ' '.runes.first))
+            return false;
+          return true;
+        }
+
+        final hasTrainNumber = isFieldMeaningful(newRecord.fullTrainNumber) &&
+            !newRecord.fullTrainNumber.contains("-----");
+
+        final hasDirection =
+            newRecord.direction == 1 || newRecord.direction == 3;
+
+        final hasLocoInfo = isFieldMeaningful(newRecord.locoType) ||
+            isFieldMeaningful(newRecord.loco);
+
+        final hasRoute = isFieldMeaningful(newRecord.route);
+
+        final hasPosition = isFieldMeaningful(newRecord.position);
+
+        final hasSpeed =
+            isFieldMeaningful(newRecord.speed) && newRecord.speed != "NUL";
+
+        final hasPositionInfo = isFieldMeaningful(newRecord.positionInfo);
+
+        final hasTrainType = isFieldMeaningful(newRecord.trainType) &&
+            newRecord.trainType != "未知";
+
+        final hasLbjClass =
+            isFieldMeaningful(newRecord.lbjClass) && newRecord.lbjClass != "NA";
+
+        final hasTrain = isFieldMeaningful(newRecord.train) &&
+            !newRecord.train.contains("-----");
+
+        if (!hasTrainNumber &&
+            !hasDirection &&
+            !hasLocoInfo &&
+            !hasRoute &&
+            !hasPosition &&
+            !hasSpeed &&
+            !hasPositionInfo &&
+            !hasTrainType &&
+            !hasLbjClass &&
+            !hasTrain) {
+          return;
+        }
+      }
+
       final isNewRecord = !_displayItems.any((item) {
         if (item is TrainRecord) {
           return item.uniqueId == newRecord.uniqueId;
@@ -123,44 +255,29 @@ class HistoryScreenState extends State<HistoryScreen> {
 
       if (!isNewRecord) return;
 
+      final allRecords = await DatabaseService.instance.getAllRecords();
+      final items = MergeService.getMixedList(allRecords, _mergeSettings);
+
       if (mounted) {
-        final previousScrollOffset = _scrollController.hasClients ? _scrollController.offset : 0.0;
-        final previousItemCount = _displayItems.length;
+        if (!_isAtTop) {
+          _chatObserver.standby();
+        }
 
-        final allRecords = await DatabaseService.instance.getAllRecords();
-        final items = MergeService.getMixedList(allRecords, _mergeSettings);
+        final hasDataChanged = _hasDataChanged(items);
+        if (hasDataChanged) {
+          setState(() {
+            _displayItems.clear();
+            _displayItems.addAll(items);
+          });
+        }
 
-        setState(() {
-          _displayItems.clear();
-          _displayItems.addAll(items);
-        });
-
-        if (_scrollController.hasClients) {
-          if (_isAtTop) {
-            _scrollController.jumpTo(0.0);
-          } else {
-            final newItemCount = items.length;
-            final itemDifference = newItemCount - previousItemCount;
-            
-            if (itemDifference > 0 && previousScrollOffset > 0) {
-              final itemHeight = _getEstimatedItemHeight();
-              final adjustedOffset = previousScrollOffset + (itemDifference * itemHeight);
-                          
-              _scrollController.jumpTo(adjustedOffset.clamp(0.0, _scrollController.position.maxScrollExtent));
-            }
-          }
+        if (_isAtTop && _scrollController.hasClients) {
+          _scrollController.jumpTo(0.0);
         }
       }
     } catch (e) {}
   }
 
-  double _getEstimatedItemHeight() {
-    if (_itemHeightCache > 0) {
-      return _itemHeightCache;
-    }
-    return 85.0;
-  }
-
   bool _hasDataChanged(List<Object> newItems) {
     if (_displayItems.length != newItems.length) return true;
 
@@ -194,8 +311,12 @@ class HistoryScreenState extends State<HistoryScreen> {
         Text('暂无记录', style: TextStyle(color: Colors.white, fontSize: 18))
       ]));
     }
-    return ListView.builder(
+    return ListViewObserver(
+      controller: _observerController,
+      child: ListView.builder(
         controller: _scrollController,
+        physics: ChatObserverClampingScrollPhysics(observer: _chatObserver),
+        shrinkWrap: _chatObserver.isShrinkWrap,
         padding: const EdgeInsets.all(16.0),
         itemCount: _displayItems.length,
         itemBuilder: (context, index) {
@@ -203,10 +324,12 @@ class HistoryScreenState extends State<HistoryScreen> {
           if (item is MergedTrainRecord) {
             return _buildMergedRecordCard(item);
           } else if (item is TrainRecord) {
-            return _buildRecordCard(item);
+            return _buildRecordCard(item, key: ValueKey(item.uniqueId));
           }
           return const SizedBox.shrink();
-        });
+        },
+      ),
+    );
   }
 
   Widget _buildMergedRecordCard(MergedTrainRecord mergedRecord) {
@@ -506,7 +629,8 @@ class HistoryScreenState extends State<HistoryScreen> {
     return 10.0;
   }
 
-  Widget _buildRecordCard(TrainRecord record, {bool isSubCard = false}) {
+  Widget _buildRecordCard(TrainRecord record,
+      {bool isSubCard = false, Key? key}) {
     final isSelected = _selectedRecords.contains(record.uniqueId);
     final isExpanded =
         !isSubCard && (_expandedStates[record.uniqueId] ?? false);
@@ -514,7 +638,7 @@ class HistoryScreenState extends State<HistoryScreen> {
     final GlobalKey itemKey = GlobalKey();
 
     final Widget card = Card(
-        key: itemKey,
+        key: key ?? itemKey,
         color: isSelected && _isEditMode
             ? const Color(0xFF2E2E2E)
             : const Color(0xFF1E1E1E),
@@ -541,15 +665,23 @@ class HistoryScreenState extends State<HistoryScreen> {
                 });
               } else if (!isSubCard) {
                 if (isExpanded) {
-                  setState(() {
-                    _expandedStates[record.uniqueId] = false;
-                    _mapOptimalZoom.remove(record.uniqueId);
-                    _mapCalculating.remove(record.uniqueId);
-                  });
+                  final shouldUpdate =
+                      _expandedStates[record.uniqueId] == true ||
+                          _mapOptimalZoom.containsKey(record.uniqueId) ||
+                          _mapCalculating.containsKey(record.uniqueId);
+                  if (shouldUpdate) {
+                    setState(() {
+                      _expandedStates[record.uniqueId] = false;
+                      _mapOptimalZoom.remove(record.uniqueId);
+                      _mapCalculating.remove(record.uniqueId);
+                    });
+                  }
                 } else {
-                  setState(() {
-                    _expandedStates[record.uniqueId] = true;
-                  });
+                  if (_expandedStates[record.uniqueId] != true) {
+                    setState(() {
+                      _expandedStates[record.uniqueId] = true;
+                    });
+                  }
                 }
               }
             },
@@ -568,12 +700,13 @@ class HistoryScreenState extends State<HistoryScreen> {
                       _buildRecordHeader(record),
                       _buildPositionAndSpeed(record),
                       _buildLocoInfo(record),
-                      if (isExpanded) _buildExpandedContent(record)
+                      if (isExpanded) _buildExpandedContent(record),
                     ]))));
 
     WidgetsBinding.instance.addPostFrameCallback((_) {
       if (_itemHeightCache <= 0 && itemKey.currentContext != null) {
-        final RenderBox renderBox = itemKey.currentContext!.findRenderObject() as RenderBox;
+        final RenderBox renderBox =
+            itemKey.currentContext!.findRenderObject() as RenderBox;
         final double realHeight = renderBox.size.height;
         if (realHeight > 0) {
           setState(() {
@@ -588,8 +721,6 @@ class HistoryScreenState extends State<HistoryScreen> {
 
   Widget _buildRecordHeader(TrainRecord record, {bool isMerged = false}) {
     final trainType = record.trainType;
-    final trainDisplay =
-        record.fullTrainNumber.isEmpty ? "未知列车" : record.fullTrainNumber;
     String formattedLocoInfo = "";
     if (record.locoType.isNotEmpty && record.loco.isNotEmpty) {
       final shortLoco = record.loco.length > 5
@@ -601,6 +732,22 @@ class HistoryScreenState extends State<HistoryScreen> {
     } else if (record.loco.isNotEmpty) {
       formattedLocoInfo = record.loco;
     }
+
+    if (record.fullTrainNumber.isEmpty && formattedLocoInfo.isEmpty) {
+      return Text(
+          (record.time == "<NUL>" || record.time.isEmpty)
+              ? record.receivedTimestamp.toString().split(".")[0]
+              : record.time.split("\n")[0],
+          style: const TextStyle(fontSize: 11, color: Colors.grey),
+          overflow: TextOverflow.ellipsis);
+    }
+
+    final hasTrainNumber = record.fullTrainNumber.isNotEmpty;
+    final hasDirection = record.direction == 1 || record.direction == 3;
+    final hasLocoInfo =
+        formattedLocoInfo.isNotEmpty && formattedLocoInfo != "<NUL>";
+    final shouldShowTrainRow = hasTrainNumber || hasDirection || hasLocoInfo;
+
     return Column(crossAxisAlignment: CrossAxisAlignment.start, children: [
       Row(mainAxisAlignment: MainAxisAlignment.spaceBetween, children: [
         Flexible(
@@ -616,43 +763,47 @@ class HistoryScreenState extends State<HistoryScreen> {
                   style: const TextStyle(fontSize: 11, color: Colors.grey),
                   overflow: TextOverflow.ellipsis))
       ]),
-      const SizedBox(height: 2),
-      Row(
-          mainAxisAlignment: MainAxisAlignment.spaceBetween,
-          crossAxisAlignment: CrossAxisAlignment.center,
-          children: [
-            Flexible(
-                child: Row(
-                    mainAxisSize: MainAxisSize.min,
-                    crossAxisAlignment: CrossAxisAlignment.center,
-                    children: [
-                  Flexible(
-                      child: Text(trainDisplay,
-                          style: const TextStyle(
-                              fontSize: 20,
-                              fontWeight: FontWeight.bold,
-                              color: Colors.white),
-                          overflow: TextOverflow.ellipsis)),
-                  const SizedBox(width: 6),
-                  if (record.direction == 1 || record.direction == 3)
-                    Container(
-                        width: 20,
-                        height: 20,
-                        decoration: BoxDecoration(
-                            color: Colors.white,
-                            borderRadius: BorderRadius.circular(2)),
-                        child: Center(
-                            child: Text(record.direction == 1 ? "下" : "上",
-                                style: const TextStyle(
-                                    fontSize: 12,
-                                    fontWeight: FontWeight.bold,
-                                    color: Colors.black))))
-                ])),
-            if (formattedLocoInfo.isNotEmpty && formattedLocoInfo != "<NUL>")
-              Text(formattedLocoInfo,
-                  style: const TextStyle(fontSize: 14, color: Colors.white70))
-          ]),
-      const SizedBox(height: 2)
+      if (shouldShowTrainRow) ...[
+        const SizedBox(height: 2),
+        Row(
+            mainAxisAlignment: MainAxisAlignment.spaceBetween,
+            crossAxisAlignment: CrossAxisAlignment.center,
+            children: [
+              Flexible(
+                  child: Row(
+                      mainAxisSize: MainAxisSize.min,
+                      crossAxisAlignment: CrossAxisAlignment.center,
+                      children: [
+                    if (hasTrainNumber)
+                      Flexible(
+                          child: Text(record.fullTrainNumber,
+                              style: const TextStyle(
+                                  fontSize: 20,
+                                  fontWeight: FontWeight.bold,
+                                  color: Colors.white),
+                              overflow: TextOverflow.ellipsis)),
+                    if (hasTrainNumber && hasDirection)
+                      const SizedBox(width: 6),
+                    if (hasDirection)
+                      Container(
+                          width: 20,
+                          height: 20,
+                          decoration: BoxDecoration(
+                              color: Colors.white,
+                              borderRadius: BorderRadius.circular(2)),
+                          child: Center(
+                              child: Text(record.direction == 1 ? "下" : "上",
+                                  style: const TextStyle(
+                                      fontSize: 12,
+                                      fontWeight: FontWeight.bold,
+                                      color: Colors.black))))
+                  ])),
+              if (hasLocoInfo)
+                Text(formattedLocoInfo,
+                    style: const TextStyle(fontSize: 14, color: Colors.white70))
+            ]),
+        const SizedBox(height: 2)
+      ]
     ]);
   }
 

lib/screens/main_screen.dart

@@ -397,7 +397,7 @@ class _MainScreenState extends State<MainScreen> with WidgetsBindingObserver {
         selectedIndex: _currentIndex,
         onDestinationSelected: (index) {
           if (_currentIndex == 2 && index == 0) {
-            _historyScreenKey.currentState?.loadRecords();
+            _historyScreenKey.currentState?.reloadRecords();
           }
           setState(() {
             if (_isHistoryEditMode) _isHistoryEditMode = false;

lib/screens/settings_screen.dart

@@ -32,6 +32,7 @@ class _SettingsScreenState extends State<SettingsScreen> {
   bool _notificationsEnabled = true;
   int _recordCount = 0;
   bool _mergeRecordsEnabled = false;
+  bool _hideTimeOnlyRecords = false;
   GroupBy _groupBy = GroupBy.trainAndLoco;
   TimeWindow _timeWindow = TimeWindow.unlimited;
 
@@ -61,6 +62,7 @@ class _SettingsScreenState extends State<SettingsScreen> {
             (settingsMap['backgroundServiceEnabled'] ?? 0) == 1;
         _notificationsEnabled = (settingsMap['notificationEnabled'] ?? 1) == 1;
         _mergeRecordsEnabled = settings.enabled;
+        _hideTimeOnlyRecords = (settingsMap['hideTimeOnlyRecords'] ?? 0) == 1;
         _groupBy = settings.groupBy;
         _timeWindow = settings.timeWindow;
       });
@@ -82,6 +84,7 @@ class _SettingsScreenState extends State<SettingsScreen> {
       'backgroundServiceEnabled': _backgroundServiceEnabled ? 1 : 0,
       'notificationEnabled': _notificationsEnabled ? 1 : 0,
       'mergeRecordsEnabled': _mergeRecordsEnabled ? 1 : 0,
+      'hideTimeOnlyRecords': _hideTimeOnlyRecords ? 1 : 0,
       'groupBy': _groupBy.name,
       'timeWindow': _timeWindow.name,
     });
@@ -236,6 +239,29 @@ class _SettingsScreenState extends State<SettingsScreen> {
                 ),
               ],
             ),
+            const SizedBox(height: 16),
+            Row(
+              mainAxisAlignment: MainAxisAlignment.spaceBetween,
+              children: [
+                Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    Text('隐藏只有时间有效的记录', style: AppTheme.bodyLarge),
+                    Text('不显示只有时间信息的记录', style: AppTheme.caption),
+                  ],
+                ),
+                Switch(
+                  value: _hideTimeOnlyRecords,
+                  onChanged: (value) {
+                    setState(() {
+                      _hideTimeOnlyRecords = value;
+                    });
+                    _saveSettings();
+                  },
+                  activeColor: Theme.of(context).colorScheme.primary,
+                ),
+              ],
+            ),
           ],
         ),
       ),

lib/services/database_service.dart

@@ -13,7 +13,7 @@ class DatabaseService {
   DatabaseService._internal();
 
   static const String _databaseName = 'train_database';
-  static const _databaseVersion = 1;
+  static const _databaseVersion = 2;
 
   static const String trainRecordsTable = 'train_records';
   static const String appSettingsTable = 'app_settings';
@@ -34,9 +34,17 @@ class DatabaseService {
       path,
       version: _databaseVersion,
       onCreate: _onCreate,
+      onUpgrade: _onUpgrade,
     );
   }
 
+  Future<void> _onUpgrade(Database db, int oldVersion, int newVersion) async {
+    if (oldVersion < 2) {
+      await db.execute(
+          'ALTER TABLE $appSettingsTable ADD COLUMN hideTimeOnlyRecords INTEGER NOT NULL DEFAULT 0');
+    }
+  }
+
   Future<void> _onCreate(Database db, int version) async {
     await db.execute('''
       CREATE TABLE IF NOT EXISTS $trainRecordsTable (
@@ -79,6 +87,7 @@ class DatabaseService {
         backgroundServiceEnabled INTEGER NOT NULL DEFAULT 0,
         notificationEnabled INTEGER NOT NULL DEFAULT 0,
         mergeRecordsEnabled INTEGER NOT NULL DEFAULT 0,
+        hideTimeOnlyRecords INTEGER NOT NULL DEFAULT 0,
         groupBy TEXT NOT NULL DEFAULT 'trainAndLoco',
         timeWindow TEXT NOT NULL DEFAULT 'unlimited'
       )
@@ -102,6 +111,7 @@ class DatabaseService {
       'backgroundServiceEnabled': 0,
       'notificationEnabled': 0,
       'mergeRecordsEnabled': 0,
+      'hideTimeOnlyRecords': 0,
       'groupBy': 'trainAndLoco',
       'timeWindow': 'unlimited',
     });

lib/services/merge_service.dart

@@ -5,7 +5,7 @@ class MergeService {
   static String? _generateGroupKey(TrainRecord record, GroupBy groupBy) {
     final train = record.train.trim();
     final loco = record.loco.trim();
-    final hasTrain = train.isNotEmpty && train != "<NUL>";
+    final hasTrain = train.isNotEmpty && train != "<NUL>" && !train.contains("-----");
     final hasLoco = loco.isNotEmpty && loco != "<NUL>";
 
     switch (groupBy) {

pubspec.lock

@@ -920,6 +920,14 @@ packages:
       url: "https://pub.flutter-io.cn"
     source: hosted
     version: "0.28.0"
+  scrollview_observer:
+    dependency: "direct main"
+    description:
+      name: scrollview_observer
+      sha256: c2f713509f18f88f637b2084b47a90c91fb1ef066d5d82d2cf3194d8509dc6ab
+      url: "https://pub.flutter-io.cn"
+    source: hosted
+    version: "1.26.2"
   share_plus:
     dependency: "direct main"
     description:

pubspec.yaml

@@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 0.2.0-flutter+20  # versionName: 0.2.0-flutter, versionCode: 3
+version: 0.3.0-flutter+30
 
 environment:
   sdk: ^3.5.4
@@ -53,6 +53,7 @@ dependencies:
   package_info_plus: ^8.1.2
   msix: ^3.16.12
   flutter_background_service: ^5.1.0
+  scrollview_observer: ^1.20.0
 
 dev_dependencies:
   flutter_test: