feat:重构代办事项模块

lib/layout/main_screen.dart

@@ -7,29 +7,29 @@ import 'package:flisp_app/provider/app_provider.dart';
 import 'package:flutter/material.dart';
 import 'package:provider/provider.dart';
 
-class MainScreen extends StatelessWidget {
+class MainScreen extends StatefulWidget {
   const MainScreen({super.key});
 
+  @override
+  State<MainScreen> createState() => _MainScreenState();
+}
+
+class _MainScreenState extends State<MainScreen> {
+  final GlobalKey<TodoPageState> _todoPageKey = GlobalKey();
+
   @override
   Widget build(BuildContext context) {
     return Consumer<AppProvider>(
       builder: (context, appState, child) {
         return Scaffold(
-          // 侧边抽屉菜单
           drawer: const AppDrawer(),
-
-          // 顶部导航栏
           appBar: AppBar(
-            title: const Text('闪灵'),
+            title: Text(_getAppBarTitle(appState.currentIndex)),
             backgroundColor: Colors.blue,
             foregroundColor: Colors.white,
             elevation: 0,
           ),
-
-          // 主体内容
           body: _buildPage(appState.currentIndex),
-
-          // 底部导航栏
           bottomNavigationBar: BottomNavigationBar(
             currentIndex: appState.currentIndex,
             onTap: (index) => appState.changeTab(index),
@@ -53,12 +53,50 @@ class MainScreen extends StatelessWidget {
               ),
             ],
           ),
+          floatingActionButton: _buildFloatingActionButton(appState.currentIndex),
         );
       },
     );
   }
 
-  // 根据索引构建对应页面
+  Widget? _buildFloatingActionButton(int currentIndex) {
+    if (currentIndex == 2) {
+      return FloatingActionButton(
+        onPressed: _showAddTodoDialog,
+        backgroundColor: Colors.transparent,
+        elevation: 0,
+        child: Container(
+          width: 50,
+          height: 50,
+          decoration: BoxDecoration(
+            shape: BoxShape.circle,
+            gradient: LinearGradient(
+              colors: [Colors.orange.shade300, Colors.orange.shade500],
+              begin: Alignment.topLeft,
+              end: Alignment.bottomRight,
+            ),
+            boxShadow: [
+              BoxShadow(
+                color: Colors.orange.shade100,
+                blurRadius: 12,
+                offset: Offset(0, 6),
+              ),
+            ],
+          ),
+          child: Icon(Icons.add, color: Colors.white, size: 36),
+        ),
+      );
+    }
+    return null;
+  }
+
+  void _showAddTodoDialog() {
+    // 通过 GlobalKey 调用 TodoPage 的方法
+    if (_todoPageKey.currentState != null) {
+      _todoPageKey.currentState!.showAddTodoDialog();
+    }
+  }
+
   Widget _buildPage(int index) {
     switch (index) {
       case 0:
@@ -66,11 +104,21 @@ class MainScreen extends StatelessWidget {
       case 1:
         return const NotesPage();
       case 2:
-        return const TodoPage();
+        return TodoPage(key: _todoPageKey); // 传递 key
       case 3:
         return const RemindersPage();
       default:
         return const FlashPage();
     }
   }
+
+  String _getAppBarTitle(int index) {
+    final titles = {
+      0: '闪灵',
+      1: '笔记',
+      2: '待办事项',
+      3: '提醒任务',
+    };
+    return titles[index] ?? '闪灵';
+  }
 }