新增搜索框控件，并调整布局

lib/presentation/screens/home/home_screen.dart

@@ -17,7 +17,10 @@ class HomeScreen extends StatelessWidget {
           if (authProvider.isAuthenticated)
             IconButton(
               icon: const Icon(Icons.notifications_none),
-              onPressed: () {},
+              onPressed: () {
+                // 进入消息中心界面
+                // Navigator.of(context).pushNamed('/login');
+              },
             ),
         ],
       ),

lib/presentation/screens/news/news_screen.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 import '../../navigation/bottom_nav_bar.dart';
+import '../../widgets/common/app_search_bar.dart';
 
 class NewsScreen extends StatelessWidget {
   const NewsScreen({super.key});
@@ -9,19 +10,41 @@ class NewsScreen extends StatelessWidget {
     return Scaffold(
       appBar: AppBar(
         title: const Text('推荐'),
-        actions: [
-          IconButton(
-            icon: const Icon(Icons.search),
-            onPressed: () {},
-          ),
-        ],
       ),
-      body: ListView.builder(
-        padding: const EdgeInsets.all(16),
-        itemCount: 10,
-        itemBuilder: (context, index) {
-          return _buildNewsCard(index);
-        },
+      body: SingleChildScrollView(
+        padding: const EdgeInsets.all(20),
+        child: Column(
+          crossAxisAlignment: CrossAxisAlignment.start,
+          children: [
+            // 使用 StatefulWidget 搜索框
+            SearchBarCustom(
+              hintText: '搜索...',
+              onSearch: (query) {
+                // 处理搜索逻辑
+                // print('搜索: $query');
+              },
+              onChanged: (query) {
+                // 实时搜索
+                // print('输入变化: $query');
+              },
+              onClear: () {
+                // print('清除搜索');
+              },
+            ),
+            const SizedBox(height: 30),
+
+            // 推荐列表
+            ListView.builder(
+              // padding: const EdgeInsets.all(16),
+              shrinkWrap: true,
+              physics: const NeverScrollableScrollPhysics(),
+              itemCount: 10,
+              itemBuilder: (context, index) {
+                return _buildNewsCard(index);
+              },
+            ),
+          ],
+        ),
       ),
       bottomNavigationBar: const BottomNavBar(initialIndex: 1),
     );

lib/presentation/screens/services/services_screen.dart

@@ -15,26 +15,6 @@ class ServicesScreen extends StatelessWidget {
         child: Column(
           crossAxisAlignment: CrossAxisAlignment.start,
           children: [
-            // 搜索框
-            Container(
-              decoration: BoxDecoration(
-                color: Colors.grey[100],
-                borderRadius: BorderRadius.circular(25),
-              ),
-              child: TextField(
-                decoration: InputDecoration(
-                  hintText: '搜索服务...',
-                  border: InputBorder.none,
-                  prefixIcon: const Icon(Icons.search),
-                  contentPadding: const EdgeInsets.symmetric(
-                    vertical: 15,
-                    horizontal: 20,
-                  ),
-                ),
-              ),
-            ),
-            const SizedBox(height: 30),
-            
             // 服务分类
             const Text(
               '服务分类',

lib/presentation/widgets/common/app_search_bar.dart

@@ -0,0 +1,72 @@
+// 独立的搜索框组件
+import 'package:flutter/material.dart';
+
+class SearchBarCustom extends StatefulWidget {
+  final ValueChanged<String>? onSearch;
+  final ValueChanged<String>? onChanged;
+  final VoidCallback? onClear;
+  final String hintText;
+  
+  const SearchBarCustom({
+    super.key,
+    this.onSearch,
+    this.onChanged,
+    this.onClear,
+    this.hintText = '搜索...',
+  });
+  
+  @override
+  State<SearchBarCustom> createState() => _SearchBarCustomState();
+}
+
+class _SearchBarCustomState extends State<SearchBarCustom> {
+  final TextEditingController _controller = TextEditingController();
+  final FocusNode _focusNode = FocusNode();
+  
+  @override
+  void dispose() {
+    _controller.dispose();
+    _focusNode.dispose();
+    super.dispose();
+  }
+  
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      decoration: BoxDecoration(
+        color: Colors.grey[100],
+        borderRadius: BorderRadius.circular(15),
+      ),
+      child: TextField(
+        controller: _controller,
+        focusNode: _focusNode,
+        decoration: InputDecoration(
+          hintText: widget.hintText,
+          border: InputBorder.none,
+          prefixIcon: const Icon(Icons.search),
+          suffixIcon: _controller.text.isNotEmpty
+              ? IconButton(
+                  icon: const Icon(Icons.clear),
+                  onPressed: () {
+                    _controller.clear();
+                    widget.onClear?.call();
+                  },
+                )
+              : null,
+          contentPadding: const EdgeInsets.symmetric(
+            vertical: 15,
+            horizontal: 20,
+          ),
+        ),
+        onChanged: (value) {
+          setState(() {}); // 更新清除按钮显示
+          widget.onChanged?.call(value);
+        },
+        onSubmitted: (value) {
+          widget.onSearch?.call(value);
+          _focusNode.unfocus();
+        },
+      ),
+    );
+  }
+}