https://doc.yunxin.163.com/messaging/references/flutter/dartdoc/Latest/zh/nim_core/NIMMessage/NIMMessage.tipEmptyMessage.html
NIMMessage.tipEmptyMessage constructor - NIMMessage - nim_core library - Dart API
API docs for the NIMMessage.tipEmptyMessage constructor from Class NIMMessage from the nim_core library, for the Dart programming language.
core libraryconstructornimdartapi