reference to connect is ambiguous QQuickItem QMainWindow

Question

I am trying to use QCustomPlot's example of the following folder, in my program:

/examples/plots

and at the same time I want it accessible from QML. So, I added <QQuickItem> and it resulted in the error stated in the title.

The code:

#include <QQuickItem>
#include <QMainWindow>
#include <QTimer>
#include "../../qcustomplot.h" 

namespace Ui {
class MainWindow;
}

class MainWindow :  public QQuickItem, public QMainWindow
{
  Q_OBJECT

What should I do to make it accessible from QML and solve the error too?

Answer 1

There are Qt Widgets applications and there are Qt Quick applications. Choose one.

QCustomPlot lets you create widgets for a Qt Widgets application.

You can not embed a QWidget in a Qt Quick (=QML) application. The only thing you can do to some extend is to embed QML in your Qt Widgets application. In this case your MainWindow inherits QMainWindow only and contains a QQuickView (see http://www.ics.com/blog/combining-qt-widgets-and-qml-qwidgetcreatewindowcontainer).