优化 demo

apps/im_app/lib/features/chat/presentation/chat_db_test_state.dart

@@ -0,0 +1,39 @@
+// 数据库测试页状态（Demo，正式开发后随页面一并删除）
+
+/// 单条测试结果记录
+class TestResult {
+  final String title;
+  final String subtitle;
+  final String duration;
+
+  TestResult({
+    required this.title,
+    required this.subtitle,
+    required this.duration,
+  });
+}
+
+class ChatDbTestState {
+  final bool testStarted;
+  final List<TestResult> testResults;
+  final String currentState;
+
+  const ChatDbTestState({
+    this.testStarted = false,
+    this.testResults = const [],
+    this.currentState = '',
+  });
+
+  /// 按钮文案（Widget 直接读，不在 View 层做判断）
+  String get buttonLabel => testStarted ? '结束' : '开始';
+
+  ChatDbTestState copyWith({
+    bool? testStarted,
+    List<TestResult>? testResults,
+    String? currentState,
+  }) => ChatDbTestState(
+    testStarted: testStarted ?? this.testStarted,
+    testResults: testResults ?? this.testResults,
+    currentState: currentState ?? this.currentState,
+  );
+}

apps/im_app/lib/features/chat/presentation/chat_db_test_view_model.dart

@@ -6,42 +6,12 @@ import 'package:im_app/app/di/db_provider.dart';
 import 'package:im_app/data/local/drift/app_database.dart';
 import 'package:riverpod_annotation/riverpod_annotation.dart';
 
+import 'chat_db_test_state.dart';
+
+export 'chat_db_test_state.dart';
+
 part 'chat_db_test_view_model.g.dart';
 
-class TestResult {
-  final String title;
-  final String subtitle;
-  final String duration;
-
-  TestResult({
-    required this.title,
-    required this.subtitle,
-    required this.duration,
-  });
-}
-
-class ChatDbTestState {
-  final bool testStarted;
-  final List<TestResult> testResults;
-  final String currentState;
-
-  const ChatDbTestState({
-    this.testStarted = false,
-    this.testResults = const [],
-    this.currentState = '',
-  });
-
-  ChatDbTestState copyWith({
-    bool? testStarted,
-    List<TestResult>? testResults,
-    String? currentState,
-  }) => ChatDbTestState(
-    testStarted: testStarted ?? this.testStarted,
-    testResults: testResults ?? this.testResults,
-    currentState: currentState ?? this.currentState,
-  );
-}
-
 @riverpod
 class ChatDbTestViewModel extends _$ChatDbTestViewModel {
   @override

apps/im_app/lib/features/chat/view/chat_db_test_page.dart

@@ -30,7 +30,7 @@ class ChatDbTestPage extends ConsumerWidget {
               mainAxisAlignment: MainAxisAlignment.spaceBetween,
               children: [
                 AppButton.inverse(
-                  label: state.testStarted ? '结束' : '开始',
+                  label: state.buttonLabel,
                   onPressed: () => vm.toggleDBTest(),
                 ),
                 SizedBox(width: 8),

apps/im_app/lib/features/settings/view/theme_view.dart

@@ -16,32 +16,27 @@ class ThemeView extends ConsumerWidget {
     final current = ref.watch(themeViewModelProvider);
 
     return Scaffold(
-      appBar: AppBar(
-        title: const Text('主题'),
-      ),
+      appBar: AppBar(title: const Text('主题')),
       body: ListView(
         children: [
           const SettingsSectionHeader(title: '外观'),
           ThemeOptionTile(
             label: '跟随系统',
-            mode: ThemeMode.system,
-            current: current,
+            isSelected: current == ThemeMode.system,
             onTap: () => ref
                 .read(themeViewModelProvider.notifier)
                 .setMode(ThemeMode.system),
           ),
           ThemeOptionTile(
             label: '黑色模式',
-            mode: ThemeMode.dark,
-            current: current,
+            isSelected: current == ThemeMode.dark,
             onTap: () => ref
                 .read(themeViewModelProvider.notifier)
                 .setMode(ThemeMode.dark),
           ),
           ThemeOptionTile(
             label: '白色模式',
-            mode: ThemeMode.light,
-            current: current,
+            isSelected: current == ThemeMode.light,
             onTap: () => ref
                 .read(themeViewModelProvider.notifier)
                 .setMode(ThemeMode.light),

apps/im_app/lib/features/settings/view/widgets/theme_option_tile.dart

@@ -5,14 +5,13 @@ import '../../../../../core/ui/base/context_theme_ext.dart';
 /// 单个主题选项行
 ///
 /// 纯展示 + 事件透传，不感知任何 Provider。
-/// 由父级传入 [current] 判断选中状态，[onTap] 处理切换。
+/// 父级传入 [isSelected] 决定是否显示勾选图标，[onTap] 处理切换。
 ///
 /// 用法：
 /// ```dart
 /// ThemeOptionTile(
 ///   label: '黑色模式',
-///   mode: ThemeMode.dark,
-///   current: current,
+///   isSelected: current == ThemeMode.dark,
 ///   onTap: () => ref.read(themeViewModelProvider.notifier).setMode(ThemeMode.dark),
 /// )
 /// ```
@@ -20,20 +19,17 @@ class ThemeOptionTile extends StatelessWidget {
   const ThemeOptionTile({
     super.key,
     required this.label,
-    required this.mode,
-    required this.current,
+    required this.isSelected,
     required this.onTap,
   });
 
   final String label;
-  final ThemeMode mode;
-  final ThemeMode current;
+  final bool isSelected;
   final VoidCallback onTap;
 
   @override
   Widget build(BuildContext context) {
     final s = context.styles;
-    final isSelected = current == mode;
 
     return ListTile(
       title: Text(label),