Using Loader Objects to Access C++ Methods

[Tjsail33]

Is it possible to have QML files I load into a Loader object access C++ methods that the parent of the Loader has access to?

@
//Gives access to the main qml file
this->ui->declarativeView->rootContext()->setContextProperty("appDelegate",this);
@

@
//The Loader View that I would like to be able to use this method
//Loader is a child of a Rectangle, which is the root object
Loader {
source: "MainNode.qml"
anchors.centerIn: parent
}
@

@
//What I would like to do with the method in MainNode.qml
//MouseArea is a child of a Rectangle, which is the root of the file.
MouseArea {
anchors.fill: parent
onDoubleClicked: {
parent.width: appDelegate.getScreenWidth();
}
}
@

How would I go about implementing this interaction?

[sierdzio]

Is it not working when you just run what you wrote here?