Extending QML - Adding Types Example¶
The Adding Types Example shows how to add a new object type, Person
, to QML.
The Person
type can be used from QML like this:
import examples.adding.people
Person {
name: "Bob Jones"
shoe_size: 12
}
Declare the Person Class¶
All QML types map to C++ types. Here we declare a basic C++ Person class with the two properties we want accessible on the QML type - name and shoeSize. Although in this example we use the same name for the C++ class as the QML type, the C++ class can be named differently, or appear in a namespace.
The Person class implementation is quite basic. The property accessors simply return members of the object instance.
from PySide6.QtCore import QObject, Property
from PySide6.QtQml import QmlElement
# To be used on the @QmlElement decorator
# (QML_IMPORT_MINOR_VERSION is optional)
QML_IMPORT_NAME = "People"
QML_IMPORT_MAJOR_VERSION = 1
@QmlElement
class Person(QObject):
def __init__(self, parent=None):
super().__init__(parent)
self._name = ''
self._shoe_size = 0
@Property(str)
def name(self):
return self._name
@name.setter
def name(self, n):
self._name = n
@Property(int)
def shoe_size(self):
return self._shoe_size
@shoe_size.setter
def shoe_size(self, s):
self._shoe_size = s
Running the Example¶
The main.py file in the example includes a simple shell application that loads and runs the QML snippet shown at the beginning of this page.
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from __future__ import annotations
"""PySide6 port of the qml/examples/qml/referenceexamples/adding example from Qt v6.x"""
from pathlib import Path
import sys
from PySide6.QtCore import QCoreApplication
from PySide6.QtQml import QQmlComponent, QQmlEngine
from person import Person # noqa: F401
if __name__ == '__main__':
app = QCoreApplication(sys.argv)
engine = QQmlEngine()
engine.addImportPath(Path(__file__).parent)
component = QQmlComponent(engine)
component.loadFromModule("People", "Main")
person = component.create()
if person:
print(f"The person's name is {person.name}")
print(f"They wear a {person.shoe_size} sized shoe")
else:
print(component.errors())
del engine
sys.exit(0)
# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
from __future__ import annotations
from PySide6.QtCore import QObject, Property
from PySide6.QtQml import QmlElement
# To be used on the @QmlElement decorator
# (QML_IMPORT_MINOR_VERSION is optional)
QML_IMPORT_NAME = "People"
QML_IMPORT_MAJOR_VERSION = 1
@QmlElement
class Person(QObject):
def __init__(self, parent=None):
super().__init__(parent)
self._name = ''
self._shoe_size = 0
@Property(str)
def name(self):
return self._name
@name.setter
def name(self, n):
self._name = n
@Property(int)
def shoe_size(self):
return self._shoe_size
@shoe_size.setter
def shoe_size(self, s):
self._shoe_size = s
// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
import People
Person {
name: "Bob Jones"
shoe_size: 12
}
module People
typeinfo coercion.qmltypes
Main 1.0 Main.qml