And if we want to compare the syntax then this would be the QML equivalent:

  import QtQuick 2.9  
  import QtQuick.Controls 1.3  
  
  ApplicationWindow {  
    title: "Example"  
    visible: true  
    width: 300  
    height: 300

    Button {  
        text: "Button"  
        anchors.centerIn: parent  
        onClicked: console.log('Hello')  
    }  
  }