Hi,

Using this code in a QML program I want to change the text of a button when clicked:

main.qml:
Qt Code: 
  1. import QtQuick 2.9
  2. import QtQuick.Window 2.2
  3. import QtQuick.Controls 1.4
  4. import QtQuick.Controls.Styles 1.4
  5.  
  6. Window {
  7.     visible: true
  8.     width: 720; height: 720
  9.     color: "gray"
  10.  
  11.     Rectangle {
  12.         id: root
  13.         x: 10; y: 10
  14.         width: 300; height: 300
  15.         color: "lightblue"
  16.  
  17.         function change() {
  18.             st_text.text = "Clicked"
  19.         }
  20.  
  21.         Button {
  22.             id: b1
  23.             x: 100; y: 100
  24.             style: ButtonStyle {
  25.                 background: Rectangle {
  26.                     implicitHeight: 50
  27.                     implicitWidth: 100
  28.                     color: "lightGrey"
  29.                     border.width: 4
  30.                     border.color: "lightBlue"
  31.                     radius: 15
  32.                     Text {
  33.                         id: st_text
  34.                         anchors.centerIn: parent
  35.                         text: "Start"
  36.                         font.bold: true
  37.                         font.pixelSize: 15
  38.                         color: "green"
  39.                     }
  40.                 }
  41.             }
  42.             onClicked: root.change()
  43.         }
  44.     }
  45. }
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But when I click the button I get this error:
qrc:/main.qml:18: ReferenceError: st_text is not defined

Why and how to solve that please?