title: qt - send signal between objects in a class with different parents
body: <p>I have a class ("controller" for example) 
  and in this class, I have created many objects of different other classes
   with different parents.</p>
  
  <p>How to send signal between that classes and "controller" to call a function in "controller" class?</p>
  
  <pre><code>    #include "controller.h"
  
  
      Controller::Controller(QObject *parent) : QObject (parent){
          connect(sender(), SIGNAL(recivedCall(QString)), this, SLOT(alert(QString)));
      }
  
      void Controller::onCall(QJsonObject callinfo){
           nodes[callinfo["username"].toString()]= new PanelManager();
           nodes[callinfo["username"].toString()]-&gt;handleCallStateChanged(callinfo);
      }
  
      void Controller::alert(QString callinfo){
          qDebug()&lt;&lt;callinfo;
      }
  </code></pre>
  
  <p>For example, how to send signal from  "recivedCall" in each "PanelManager" object to call "alert" function in "controller" class ?</p>