Qt:没有这样的槽QObject::SlotName(QNetworkReply*)

I am new to QT, and I am trying to connect to a REST service and get data. I am able to successfully connect to the local tomcat on my machine, but I am getting the slot not found error. Kindly let me know what I might be doing wrong, I don't have that much expertise in Qt, so please bear with me I am new to QT, and I am trying to connect to a