修改bug

ios/Classes/Module/MessageManager.swift

@@ -261,7 +261,7 @@ public class MessageManager: BaseServiceManager {
     }
 
     func fetchSurroundingMessages(methodCall: FlutterMethodCall, result: @escaping FlutterResult){
-        callBack(result, Open_im_sdkFetchSurroundingMessages(methodCall[string: "operationID"], methodCall[jsonString: "message"], methodCall[int: "before"], methodCall[int: "after"]))
+        Open_im_sdkFetchSurroundingMessages(BaseCallback(result: result),methodCall[string: "operationID"], methodCall[jsonString: "message"], methodCall[int: "before"], methodCall[int: "after"])
     }
 
 

lib/src/manager/im_message_manager.dart

@@ -836,10 +836,7 @@ class MessageManager {
                 'after': after ?? 0,
                 'operationID': Utils.checkOperationID(operationID),
               }))
-          .then((value) {
+          .then((value) => Utils.toList(value, (map) => Message.fromJson(map)));
-        final result = Utils.toListMap(value);
-        return List<Message>.from(result);
-      });
 
   static Map _buildParam(Map<String, dynamic> param) {
     param["ManagerName"] = "messageManager";