QQmlApplicationEngine¶
QQmlApplicationEngine
provides a convenient way to load an application from a single QML file. More…

Synopsis¶
Functions¶
def
rootObjects
()
Slots¶
def
load
(filePath)def
load
(url)def
loadData
(data[, url=QUrl()])def
setExtraFileSelectors
(extraFileSelectors)def
setInitialProperties
(initialProperties)
Signals¶
def
objectCreated
(object, url)
Detailed Description¶
This class combines a QQmlEngine
and QQmlComponent
to provide a convenient way to load a single QML file. It also exposes some central application functionality to QML, which a C++/QML hybrid application would normally control from C++.
It can be used like so:
#include <QGuiApplication> #include <QQmlApplicationEngine> int main(int argc, char *argv[]) { QGuiApplication app(argc, argv); QQmlApplicationEngine engine("main.qml"); return app.exec(); }
Unlike QQuickView
, QQmlApplicationEngine
does not automatically create a root window. If you are using visual items from Qt Quick, you will need to place them inside of a Window .
You can also use QCoreApplication
with QQmlApplicationEngine
, if you are not using any QML modules which require a QGuiApplication
(such as QtQuick
).
List of configuration changes from a default QQmlEngine
:
Translations are reloaded when the
QJSEngine::uiLanguage
/Qt.uiLanguage
property is changed.Automatically sets an incubation controller if the scene contains a
QQuickWindow
.Automatically sets a
QQmlFileSelector
as the url interceptor, applying file selectors to all QML files and assets.
The engine behavior can be further tweaked by using the inherited methods from QQmlEngine
.
- class PySide6.QtQml.QQmlApplicationEngine([parent=None])¶
PySide6.QtQml.QQmlApplicationEngine(filePath[, parent=None])
PySide6.QtQml.QQmlApplicationEngine(url[, parent=None])
- Parameters
filePath – str
url –
PySide6.QtCore.QUrl
parent –
PySide6.QtCore.QObject
Create a new QQmlApplicationEngine
with the given parent
. You will have to call load()
later in order to load a QML file.
- PySide6.QtQml.QQmlApplicationEngine.load(filePath)¶
- Parameters
filePath – str
- PySide6.QtQml.QQmlApplicationEngine.load(url)
- Parameters
url –
PySide6.QtCore.QUrl
- PySide6.QtQml.QQmlApplicationEngine.loadData(data[, url=QUrl()])¶
- Parameters
data –
PySide6.QtCore.QByteArray
url –
PySide6.QtCore.QUrl
Loads the QML given in data
. The object tree defined by data
is instantiated immediately.
If a url
is specified it is used as the base url of the component. This affects relative paths within the data and error messages.
If an error occurs, error messages are printed with qWarning
.
- PySide6.QtQml.QQmlApplicationEngine.objectCreated(object, url)¶
- Parameters
object –
PySide6.QtCore.QObject
url –
PySide6.QtCore.QUrl
- PySide6.QtQml.QQmlApplicationEngine.rootObjects()¶
- Return type
Returns a list of all the root objects instantiated by the QQmlApplicationEngine
. This will only contain objects loaded via load()
or a convenience constructor.
Note
In Qt versions prior to 5.9, this function is marked as non-const
.
- PySide6.QtQml.QQmlApplicationEngine.setExtraFileSelectors(extraFileSelectors)¶
- Parameters
extraFileSelectors – list of strings
Sets the extraFileSelectors
to be passed to the internal QQmlFileSelector
used for resolving URLs to local files. The extraFileSelectors
are applied when the first QML file is loaded. Setting them afterwards has no effect.
See also
QQmlFileSelector
setExtraSelectors
- PySide6.QtQml.QQmlApplicationEngine.setInitialProperties(initialProperties)¶
- Parameters
initialProperties –
Sets the initialProperties
with which the QML component gets initialized after it gets loaded.
QQmlApplicationEngine engine; EventDatabase eventDatabase; EventMonitor eventMonitor; engine.setInitialProperties({ { "eventDatabase", QVariant::fromValue(&eventDatabase) }, { "eventMonitor", QVariant::fromValue(&eventMonitor) } });See also
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