feat:增加加载中显示

lib/pages/category_page.dart

@@ -1,5 +1,6 @@
-import 'package:blog_app/apis/blog.dart';
-import 'package:blog_app/models/blog.dart';
+import 'package:blog_app/widget/common.dart';
+import 'package:provider/provider.dart';
+import 'package:blog_app/provider/blog.dart';
 import 'package:blog_app/widget/blog.dart';
 import 'package:flutter/material.dart';
 
@@ -11,38 +12,34 @@ class CategoryPage extends StatefulWidget {
 }
 
 class _CategoryPageState extends State<CategoryPage> {
-  late List<BlogCategory> categories = [];
-
   @override
   void initState() {
     super.initState();
-    _loadBlogCategory();
+    // 初始化加载数据
+    WidgetsBinding.instance.addPostFrameCallback((_) {
+      context.read<BlogProvider>().refreshBlogCategory();
+    });
   }
 
-  Future<void> _loadBlogCategory() async {
-    try {
-      final result = await queryBlogCategoryApi();
-      setState(() {
-        categories = result;
-      });
-    } catch (e) {
-      throw Exception('获取博客分类失败: $e');
+  Widget _buildContent(BlogProvider provider) {
+    if (provider.error != null) {
+      return buildErrorInfo(
+        errorInfo: provider.error!,
+        onPressed: () => provider.refreshBlogByYear(),
+      );
     }
-  }
 
-  @override
-  Widget build(BuildContext context) {
     return Column(
       crossAxisAlignment: CrossAxisAlignment.start,
       children: [
-        buildCategoryTitle(context, categories.length),
+        buildCategoryTitle(context, provider.categoryList.length),
         SizedBox(height: 10),
         // 分类列表
         Expanded(
           child: ListView.builder(
-            itemCount: categories.length,
+            itemCount: provider.categoryList.length,
             itemBuilder: (context, index) {
-              final category = categories[index];
+              final category = provider.categoryList[index];
               return buildCategoryCard(context, category);
             },
           ),
@@ -50,4 +47,24 @@ class _CategoryPageState extends State<CategoryPage> {
       ],
     );
   }
+
+  @override
+  Widget build(BuildContext context) {
+    final blogProvider = context.watch<BlogProvider>();
+
+    return Column(
+      children: [
+        Expanded(
+          child: Stack(
+            children: [
+              if (blogProvider.isLoading)
+                buildLoadingIndicator()
+              else
+                _buildContent(blogProvider),
+            ],
+          ),
+        ),
+      ],
+    );
+  }
 }