QQuickWidget and C++ interaction - c++

Question

I am experiencing with the new QQuickWidget. How can I interact between the QQuickWidget and C++?
C++
QQuickWidget *view = new QQuickWidget();
view->setSource(QUrl::fromLocalFile("myqml.qml"));
view->setProperty("test", 0);
myLayout->addWidget(view);
QML
import QtQuick 2.1
Rectangle {
id: mainWindow
width: parent.width
height: parent.height
Text {
id: text
width: mainWindow.width
font.pixelSize: 20
horizontalAlignment: Text.AlignHCenter
verticalAlignment: Text.AlignVCenter
text: test
}
}
text: test does not work: ReferenceError: test is not defined
How can I give my QML file some properties via C++?
Is it also possible to get the Text object in C++ and update its text?

Answer 1

Give it a try:
view->rootContext()->setContextProperty("test", "some random text");
instead of
view->setProperty("test", 0);
setProperty(name, val) works if object has the property name defined as Q_PROPERTY.
It is possible to pass QObject-derived object as view's context property:
class Controller : public QObject
{
Q_OBJECT
QString m_test;
public:
explicit Controller(QObject *parent = 0);
Q_PROPERTY(QString test READ test WRITE setTest NOTIFY testChanged)
QDate test() const
{
return m_test;
}
signals:
void testChanged(QString arg);
public slots:
void setTest(QDate arg)
{
if (m_test != arg) {
m_test = arg;
emit testChanged(arg);
}
}
};
Controller c;
view->rootContext()->setContextProperty("controller", &c);
Text {
id: text
width: mainWindow.width
font.pixelSize: 20
horizontalAlignment: Text.AlignHCenter
verticalAlignment: Text.AlignVCenter
text: controller.test
}
Is it also possible to get the Text object in C++ and update its text?
In general, it doesn't seem to be the best approach -- c++ code shouldn't be aware of presentation if it follows model-view pattern.
However it is possible as described here.