diff --git a/lib/controller.dart b/lib/controller.dart
index 27bec8c..d61432b 100644
--- a/lib/controller.dart
+++ b/lib/controller.dart
@@ -214,6 +214,12 @@ class CalendarController {
     });
   }
 
+  //可以动态修改extraDataMap
+  void changeExtraData(Map<DateModel, Object> newMap) {
+    this.calendarConfiguration.extraDataMap = newMap;
+    this.calendarProvider.generation.value++;
+  }
+
   /**
    * 月份或者星期的上一页
    */
diff --git a/lib/utils/date_util.dart b/lib/utils/date_util.dart
index 856feee..6f63d71 100644
--- a/lib/utils/date_util.dart
+++ b/lib/utils/date_util.dart
@@ -168,7 +168,11 @@ class DateUtil {
       if (extraDataMap?.isNotEmpty == true) {
         if (extraDataMap.containsKey(dateModel)) {
           dateModel.extraData = extraDataMap[dateModel];
+        }else{
+          dateModel.extraData=null;
         }
+      }else{
+        dateModel.extraData=null;
       }
 
       result.add(dateModel);
diff --git a/lib/widget/month_view.dart b/lib/widget/month_view.dart
index 010dcf0..019ea69 100644
--- a/lib/widget/month_view.dart
+++ b/lib/widget/month_view.dart
@@ -74,6 +74,16 @@ class _MonthViewState extends State<MonthView>
     }
 
     lineCount = DateUtil.getMonthViewLineCount(widget.year, widget.month);
+
+    //第一帧后
+    WidgetsBinding.instance.addPostFrameCallback((callback) {
+      Provider.of<CalendarProvider>(context, listen: false)
+          .generation
+          .addListener(() async {
+        extraDataMap={};
+        await getItems();
+      });
+    });
   }
 
   getItems() async {
@@ -130,6 +140,7 @@ class _MonthViewState extends State<MonthView>
 
           return ItemContainer(
             dateModel: dateModel,
+            key: ObjectKey(dateModel),//这里使用objectKey，保证可以刷新。原因1：跟flutter的刷新机制有关。原因2：statefulElement持有state。
           );
         });
   }