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qtqml

QT/QML Singleton Undefined Reference

I have a QML file that contains some reusable application-wide data:

CApplicationData.qml:

pragma Singleton
import QtQuick 2.6
/**
 *  Singleton object to store all application data to be shared between different .qml files.
 *  These objects are received from the cloud or they can be application specific global data.
 */
QtObject {
  ...
  property var userObject

}

I've defined qmldir file like so:

qmldir

singleton ApplicationData 1.0 CApplicationData.qml

And imported it in each of the QML files where I want to reference it like so:

CUserEditView.qml:

import QtQuick 2.6
import "." // QTBUG-34418, singletons require explicit import to load qmldir file

Component.onCompleted {
    Console.log('ApplicationData: '+ApplicationData.userObject)
}

This works fine (most places), and when I debug on my development machine, QtCreator, I can see values defined inside of UserView.qml, after I display it (as a modal):

var component = Qt.createComponent("CUserEditView.qml");
var obj = component.createObject(rootWindow, {});

However, when I compile and use qtwindeploy, I have discovered that when I attempt to dereference ApplicationData.userObject, ApplicationData.userObject is undefined inside CUserEditView undefined?

Any ideas?

Solution

  • This behavior does not seem to be documented.

    I had to create a new QML sub-directory:

    qml.qrc/applicationdata:

    /applicationdata/CApplicationData.qml
/applicationdata/qmldir

    with the contents of qmldir set to:

    singleton ApplicationData 1.0 CApplicationData.qml

    And added both files to my qml.qrc.

    This also required me to update my references in other .qml files to:

    import "qrc:/applicationdata/."