no message

android/src/main/java/io/openim/flutter_openim_sdk/manager/MessageManager.java

@@ -48,7 +48,7 @@ public class MessageManager extends BaseManager {
                 value(methodCall, "operationID"),
                 value(methodCall, "conversationID"),
                 value(methodCall, "clientMsgID"),
-                value(methodCall, "message")
+                jsonValue(methodCall, "message")
         );
     }
 

lib/src/manager/im_message_manager.dart

@@ -564,7 +564,7 @@ class MessageManager {
             'conversationID': conversationID,
             'clientMsgID': clientMsgID,
             "operationID": Utils.checkOperationID(operationID),
-            'message': message,
+            'message': message.toJson(),
           }));
 
   /// Mark messages as read