[SOLVED] Crash when using C++ to access QML Image

[drewpotter]

Hi,

I am trying to manipulate a QML Image from C++ and it causes the App to crash.

Here is the QML code:

function addMarker(id, name, image, icon, xpos, ypos, description)
{
    var test = "import QtQuick 2.4; Image { id: " + id + "; source: '" + icon  + "'; width: " + markerWidth + "; height: " + markerHeight + "; x: " + (xpos*flick.width - markerWidth/2) + "; y: " + (ypos*flick.height - markerHeight)*aspectRatio + ";}"

    Qt.createQmlObject(test,mapImage,'Object.'+id);
    markerCount++;
}

function loadMarkers()
{
    addMarker('marker1', "", "", 'qrc:/marker.png', 0.5369613596988587, 0.5081792538133771, "The front entrance of the school.");

}

loadMarkers() is called when the Application has finished loading using Component.onCompleted

Here is the C++ code:

QQuickItem *item;

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

QQmlApplicationEngine engine;
engine.load(QUrl(QStringLiteral("qrc:/main.qml")));

item = engine.rootObjects().at(0)->findChild<QQuickItem*>("marker1");
item->setProperty("color", QColor(Qt::yellow));

return app.exec();

}

Any hints would be appreciated.

[p3c0]

@drewpotter I guess it is crashing because the marker1 object is not found and you are trying to set property on that null object.
findChild requires objectName and not id.

[drewpotter]

Thanks @p3c0 you have solved my problem!

Great!