功能优化

lib/widgets/note_list_item.dart

@@ -11,6 +11,21 @@ class NoteListItem extends StatelessWidget {
 
   const NoteListItem({super.key, required this.note});
 
+  @override
+  Widget build(BuildContext context) {
+    // 使用 RepaintBoundary 减少重绘
+    return RepaintBoundary(
+      child: _NoteListItemContent(note: note),
+    );
+  }
+}
+
+/// 笔记列表项内容 - 分离出来便于优化
+class _NoteListItemContent extends StatelessWidget {
+  final Note note;
+
+  const _NoteListItemContent({required this.note});
+
   @override
   Widget build(BuildContext context) {
     final isPlainText = note.contentType == 'plain_text';
@@ -50,9 +65,9 @@ class NoteListItem extends StatelessWidget {
                   ),
                 ),
                 const SizedBox(width: 8),
-                // 时间
+                // 时间 - 使用缓存的格式化结果
                 Text(
-                  _formatDate(note.updatedAt),
+                  _formatDateCached(note.updatedAt),
                   style: const TextStyle(
                     fontSize: 11,
                     color: Color(0xFF999999),
@@ -100,18 +115,11 @@ class NoteListItem extends StatelessWidget {
                 child: ListView.builder(
                   scrollDirection: Axis.horizontal,
                   itemCount: note.images.length > 2 ? 2 : note.images.length,
+                  physics: const NeverScrollableScrollPhysics(), // 禁用滚动，提高性能
                   itemBuilder: (context, index) {
-                    return Container(
-                      width: 60,
-                      height: 60,
-                      margin: const EdgeInsets.only(right: 8),
-                      decoration: BoxDecoration(
-                        border: Border.all(color: const Color(0xFFE5E5E5)),
-                      ),
-                      child: Image.file(
-                        File(note.images[index]),
-                        fit: BoxFit.cover,
-                      ),
+                    return _NoteImage(
+                      imagePath: note.images[index],
+                      index: index,
                     );
                   },
                 ),
@@ -148,26 +156,6 @@ class NoteListItem extends StatelessWidget {
     );
   }
 
-  /// 格式化日期
-  String _formatDate(DateTime date) {
-    final now = DateTime.now();
-    final difference = now.difference(date);
-    
-    if (difference.inDays == 0) {
-      if (difference.inHours == 0) {
-        if (difference.inMinutes == 0) {
-          return '刚刚';
-        }
-        return '${difference.inMinutes}分钟前';
-      }
-      return '${difference.inHours}小时前';
-    } else if (difference.inDays < 7) {
-      return '${difference.inDays}天前';
-    } else {
-      return '${date.year}-${date.month.toString().padLeft(2, '0')}-${date.day.toString().padLeft(2, '0')}';
-    }
-  }
-
   /// 显示删除确认对话框
   void _showDeleteDialog(BuildContext context) {
     showDialog(
@@ -196,3 +184,75 @@ class NoteListItem extends StatelessWidget {
     );
   }
 }
+
+/// 笔记图片组件 - 独立出来便于优化
+class _NoteImage extends StatelessWidget {
+  final String imagePath;
+  final int index;
+
+  const _NoteImage({
+    required this.imagePath,
+    required this.index,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      width: 60,
+      height: 60,
+      margin: EdgeInsets.only(right: index < 1 ? 8 : 0),
+      decoration: BoxDecoration(
+        border: Border.all(color: const Color(0xFFE5E5E5)),
+      ),
+      child: Image.file(
+        File(imagePath),
+        fit: BoxFit.cover,
+        // 使用低内存缓存
+        cacheWidth: 120,
+        cacheHeight: 120,
+        errorBuilder: (_, __, ___) => const Icon(
+          Icons.broken_image,
+          size: 24,
+          color: Color(0xFFCCCCCC),
+        ),
+      ),
+    );
+  }
+}
+
+// 日期格式化缓存
+final Map<DateTime, String> _dateFormatCache = {};
+
+/// 格式化日期（带缓存）
+String _formatDateCached(DateTime date) {
+  // 使用日期部分作为缓存键（忽略时分秒）
+  final cacheKey = DateTime(date.year, date.month, date.day);
+  
+  if (_dateFormatCache.containsKey(cacheKey)) {
+    return _dateFormatCache[cacheKey]!;
+  }
+  
+  final result = _formatDate(date);
+  _dateFormatCache[cacheKey] = result;
+  return result;
+}
+
+/// 格式化日期
+String _formatDate(DateTime date) {
+  final now = DateTime.now();
+  final difference = now.difference(date);
+  
+  if (difference.inDays == 0) {
+    if (difference.inHours == 0) {
+      if (difference.inMinutes == 0) {
+        return '刚刚';
+      }
+      return '${difference.inMinutes}分钟前';
+    }
+    return '${difference.inHours}小时前';
+  } else if (difference.inDays < 7) {
+    return '${difference.inDays}天前';
+  } else {
+    return '${date.year}-${date.month.toString().padLeft(2, '0')}-${date.day.toString().padLeft(2, '0')}';
+  }
+}