feat:增加待办提醒功能

lib/models/task.dart

@@ -1,7 +1,7 @@
 import 'package:hive/hive.dart';
 
 // flutter packages pub run build_runner build
-// part 'todo.g.dart';
+part 'task.g.dart';
 
 @HiveType(typeId: 0)
 class Task extends HiveObject {
@@ -45,10 +45,11 @@ class Task extends HiveObject {
     this.isCompleted = false,
     Priority priority = Priority.medium,
     DateTime? createTime,
-  }) : id = id ?? DateTime.timestamp().microsecond,
+    DateTime? updateTime,
+  }) : id = id ?? DateTime.now().millisecondsSinceEpoch ~/ 1000,
        this.priorityIndex = priority.index,
-       createTime = DateTime.now(),
-       updateTime = DateTime.now();
+       createTime = createTime ?? DateTime.now(),
+       updateTime = updateTime ?? DateTime.now();
 }
 
 enum Priority { low, medium, high }