Error when using C++ class Linked to QML

AmrCoder

iam using Qt Quick Control 2 in Qt 5.7 iam try to connect a c++ class to qml i use this code in main

#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include <QQmlEngine>
#include <QQmlContext>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
    QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling);
    QGuiApplication app(argc, argv);

    qputenv("QT_QUICK_CONTROLS_STYLE", "Flat");
    
    QScopedPointer<MainWindow> MyClass(new MainWindow);
    QQmlApplicationEngine engine;
    engine.load(QUrl(QLatin1String("qrc:/Main.qml")));
    engine.rootContext()->setContextProperty("MyClass",MyClass.data());

    return app.exec();
}

the class i use
MainWindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QObject>
#include <QPoint>


class MainWindow : public QObject
{
    Q_OBJECT
public:
    explicit MainWindow(QObject *parent = 0);
    Q_INVOKABLE void check();
};

#endif // MAINWINDOW_H

and .cpp

#include "mainwindow.h"
#include <QDebug>
MainWindow::MainWindow(QObject *parent) :
    QObject(parent)
{

}

void MainWindow::check()
{
    qDebug() << "hello";
}

i can't use the MyClass in qml when i use it i get error on the line i use in qml file

qml

import QtQuick 2.4
import QtQuick 2.5
import QtQuick.Controls 2.0
import QtQuick.Dialogs 1.2
import QtQuick.Layouts 1.1
import QtQuick.Window 2.0

ApplicationWindow {
    id: window
    width: 480
    height: 480
    title: "Flat Example"
    visible: true

    MainForm {
        id: amr
        visible: true
        text3.x: amr.width / 2 - 60
        MyClass.check() // i got error here red line under this 
    }
}

when i try to run i got

qrc:/Main.qml:19 Syntax error

so what i do wrong ?
Thanks in Advance

? Offline

Hi! "MyClass.check()" is a function call. But that's not allowed there.

AmrCoder

@Wieland what should i do to use this function from c++ class ?

? Offline

That depends. When do you want to call the function?

AmrCoder

@Wieland Thank you it solve i add it to button function

        button1.onClicked: {
            MyClass.check()
        }

? Offline

@AmrCoder

First post.

You stole my Class. Amazingly this is word for word for what I'm doing at the moment with the exception of the qputenv(). Must check that! And I had the same problem and solved it in the same manner. I've just returned to programming after several years out of the game,