Need some help with connecting to a signal from coming from QML in c++.

[najamelan]

Hi,

to learn qt quick and understand better the basics, I made a hello world project in Qt Creator. Now I have thrown out the qmlapplicationviewer class in order to see the most simple functioning qml app and make sure I understand it. Now I get stuck here:

// main.cpp
 
#include <QtGui/QApplication>
#include <QDeclarativeView>
 
int main(int argc, char *argv[])
{
	 QApplication app(argc, argv);
 
 
	 QDeclarativeView view;
	 view.setSource(QUrl::fromLocalFile("qml/untitled/main.qml"));
 
	// QObject::connect( ( QObject* ) view.engine(), SIGNAL( quit() ),( QObject* ) &app, SLOT( quit() ) );
 
	 // ^--works | doesn't work --v
 
	 QObject::connect( view.engine(), SIGNAL( quit() ), &app, SLOT( quit() ) );
 
	 view.show();
 
	 return app.exec();
}

// main.cpp

#include <QtGui/QApplication>
#include <QDeclarativeView>

int main(int argc, char *argv[])
{
	 QApplication app(argc, argv);


	 QDeclarativeView view;
	 view.setSource(QUrl::fromLocalFile("qml/untitled/main.qml"));

	// QObject::connect( ( QObject* ) view.engine(), SIGNAL( quit() ),( QObject* ) &app, SLOT( quit() ) );

	 // ^--works | doesn't work --v

	 QObject::connect( view.engine(), SIGNAL( quit() ), &app, SLOT( quit() ) );

	 view.show();

	 return app.exec();
}

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When i try to build this I get the following error:

\main.cpp:13: error: no matching function for call to 'QObject::connect(QDeclarativeEngine*, const char*, QApplication*, const char*)'

qobject.h:198: note: candidates are: static bool QObject::connect(const QObject*, const char*, const QObject*, const char*, Qt::ConnectionType)
qobject.h:313: note: bool QObject::connect(const QObject*, const char*, const char*, Qt::ConnectionType) const

Note that the commented out line works as expected... I would think the upcasting should be implicit... In no sample code in the documetation do I see the need for casts...
Can anyone explain to me what is going on?

The qml file is unchanged from how the wizard generated it:

//main.qml
 
import QtQuick 1.0
 
Rectangle
{
	 width: 360
	 height: 360
 
	 Text
	 {
		  text: "Hello World"
		  anchors.centerIn: parent
	 }
 
	 MouseArea
	 {
		  anchors.fill: parent
		  onClicked:
		  {
				Qt.quit();
		  }
	 }
}

//main.qml

import QtQuick 1.0

Rectangle
{
	 width: 360
	 height: 360

	 Text
	 {
		  text: "Hello World"
		  anchors.centerIn: parent
	 }

	 MouseArea
	 {
		  anchors.fill: parent
		  onClicked:
		  {
				Qt.quit();
		  }
	 }
}

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