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C++ QML Integration Demo App

 import Felgo 4.0
 import QtQuick 2.5

 // custom import to use MyQMLType, a C++ based QML type
 // NOTE: the import identifier, version and QML type name are set in main.cpp at qmlRegisterType(...)
 import com.yourcompany.xyz 1.0

 App {
   id: app

   NavigationStack {
     AppPage {
       title: "Integrate C++ and QML"

       // Example 1 - Global Context Property
       // NOTE: myGlobalObject is available here because it is set as a context property in main.cpp
       Column {
         anchors.fill: parent
         anchors.margins: 12

         // 1.1: Calling myGlobalObject.doSomething() function
         AppButton {
           text: "myGlobalObject.doSomething()"
           onClicked: myGlobalObject.doSomething("TEXT FROM QML")
         }

         // 1.2: Increasing myGlobalObject.counter property
         // NOTE: the defined setter function of the property is used automatically and triggers the counterChanged signal
         AppButton {
           text: "myGlobalObject.counter + 1"
           onClicked: {
             myGlobalObject.counter = myGlobalObject.counter + 1
           }
         }

         // 1.3: Showing myGlobalObject counter value in a QML text
         // NOTE: property bindings are supported, as the counter property definition includes the counterChanged signal,
         // which is fired in the implementation of MyGlobalObject::setCounter() for each property change
         AppText {
           text: "Global Context Property Counter: "+myGlobalObject.counter
         }
       // Example 1 ends here...

       // Example 2: Custom QML Type implemented with C++
       // NOTE: This type is declared in main.cpp and available after using "import com.yourcompany.xyz 1.0"
       // To create a type that also has a visual representation and may contain child items, derive from QQuickItem instead of QObject
       MyQMLType {
         id: typeFromCpp

         // 2.1: Property Binding for MyQMLType::message property
         // NOTE: Similar to types created purely with QML, you may use property bindings to keep your property values updated
         message: "counter / 2 = " + Math.floor(myGlobalObject.counter / 2)

         // 2.2: Reacting to property changes
         // NOTE: With the onMessageChanged signal, you can add code to handle property changes
         onMessageChanged: console.log("typeFromCpp message changed to '"+typeFromCpp.message+"'")

         // 2.3: Run code at creation of the QML component
         // NOTE: The Component.onCompleted signal is available for every QML item, even for items defined with C++.
         // The signal is fired when the QML Engine creates the item at runtime.
         Component.onCompleted: myGlobalObject.counter = typeFromCpp.increment(myGlobalObject.counter)

         // 2.4: Handling a custom signal
         onCppTaskFinished: {
           myGlobalObject.counter = 0 // reset counter to zero, this will also update the message
         }
       }

       // 2.1: Show typeFromCpp.message value, which is calculated automatically based on the myGlobalObject.counter value
       AppText {
         text: "Custom QML Type Message:\n" + typeFromCpp.message
       }

       // 2.4: Button to start cpp task
       AppButton {
         text: "typeFromCpp.startCppTask()"
         onClicked: {
             typeFromCpp.startCppTask()
         }
       }
     }

       // 2.5: Connections allow to add signal handlers for global context property objects
       Connections {
           target: myGlobalObject
           onCounterChanged: console.log("Counter changed to "+myGlobalObject.counter)
       }
     }