add button to toggle timer

main.qml

@@ -4,6 +4,8 @@ import QtQuick.Layouts 1.12
 import QtQuick.Window 2.12
 
 Window {
+    id: root
+
     width: 640
     height: 480
     visible: true
@@ -14,15 +16,23 @@ Window {
 
         Button {
             id: button
+            Layout.alignment: Qt.AlignHCenter
             text: "Greeting to crash"
             onClicked: {
                 serviceObject.greeting();
             }
         }
+
+        Button {
+            id: timerButton
+            Layout.alignment: Qt.AlignHCenter
+            text: "start timer to destroy"
+            checkable: true
+        }
     }
 
     Timer {
-        running: true
+        running: timerButton.checked
         interval: 5000
         onTriggered: {
             console.log("triggered");