How to convert a python list to a QVariantList in PySide2

Question

So, PySide2 has removed the QVariant* types.

However, QtQuick expose a great deal of QVariant API.

More specifically, i want to use the very handy feature to pass a QVariantList as a model of ListView without having to implement a fully blown QAIM.

However, by feeding such an object to QML via setContextProperty

class Test(QObject):
   def __init__(self):

       super(Test, self).__init__()
       self.propertyList = ["FOO", "BAR", 1]

   def model(self):
       return self.propertyList

   modelChanged = Signal()
   model = Property(list, model, notify=modelChanged)

And then printing .model yields:

qml: QVariant(PySide::PyObjectWrapper)

So how to pass a python list to qml in a form that is actually understood by qml?

eyllanesc eyllanesc · Accepted Answer · 2019-06-13T21:27:40

You have to pass as type of Property to "QVariantList":

from PySide2 import QtCore, QtGui, QtQml


class Test(QtCore.QObject):
    modelChanged = QtCore.Signal()

    def __init__(self, parent=None):
        super(Test, self).__init__(parent)
        self.propertyList = ["FOO", "BAR", 1]

    def model(self):
        return self.propertyList

    model = QtCore.Property("QVariantList", fget=model, notify=modelChanged)


if __name__ == "__main__":
    import sys

    app = QtGui.QGuiApplication(sys.argv)

    pyobject = Test()

    engine = QtQml.QQmlApplicationEngine()
    ctx = engine.rootContext()
    ctx.setContextProperty("pyobject", pyobject)
    engine.load(QtCore.QUrl.fromLocalFile("main.qml"))
    engine.quit.connect(app.quit)

    sys.exit(app.exec_())

import QtQuick 2.12
import QtQuick.Window 2.12

Window{
    visible: true
    width: 640
    height: 480

    Component.onCompleted: console.log(pyobject.model)
}

Output:

qml: [FOO,BAR,1]

_{Note: In the case of PyQt5 list native of python is converted directly to the list of QML, unlike PySide2 you must indicate the types of Qt and if they do not exist directly as types you must indicate it as string.}

How to convert a python list to a QVariantList in PySide2

1 Answers