qt-creator/doc/qtcreator/src/python/creator-python-project.qdocinc

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/*!
//! [python project wizards]

    \section2 Creating Widget-Based Qt for Python Applications

    \l {https://doc.qt.io/qtforpython/index.html}{Qt for Python} enables you
    to use Qt 5 API in Python applications. You can use the PySide2 module to
    gain access to individual Qt modules, such as \l {Qt Core}, \l {Qt GUI},
    and \l {Qt Widgets}.

    The Qt for Python Application wizards generate a \c {.pyproject} file that
    lists the files in the Python project and a \c {.py} file that contains
    some boilerplate code. In addition, the widget based UI wizard creates a
    \c {.ui} file that contains a \QD form, and the Qt Quick Application wizard
    creates a \c {.qml} file that contains Qt Quick controls.

    The \c{.pyproject} files are JSON-based configuration files that replace
    the previously used \c {.pyqtc} configuration files. You can still open and
    use \c {.pyqtc} files, but we recommend that you choose \c{.pyproject} files
    for new projects.

    The \uicontrol {Qt for Python - Window (UI file)} wizard enables you to
    create a Python project that contains the source file for a class. Specify
    the class name, base class, and and source file for the class.

    \image qtcreator-python-wizard-app-window.png

    The wizard adds the imports to the source file to provide
    access to the QApplication, the base class you selected in the Qt
    Widgets module, and Qt UI tools:

    \badcode
    import sys
    import os

    from PySide2.QtWidgets import QApplication, QWidget
    from PySide2.QtCore import QFile
    from PySide2.QtUiTools import QUiLoader
    \endcode

    The wizard also adds a main class with the specified name that
    inherits from the specified base class:

    \badcode
    class MyWidget(QWidget):
        def __init__(self):
            super(MyWidget, self).__init__()
            self.load_ui()
            ...
    \endcode

    The following lines in the main class load the generated Python class from
    the UI file:

    \badcode
        def load_ui(self):
        loader = QUiLoader()
        path = os.path.join(os.path.dirname(__file__), "form.ui")
        ui_file = QFile(path)
        ui_file.open(QFile.ReadOnly)
        loader.load(ui_file, self)
        ui_file.close()
    \endcode

    Next, the wizard adds a main function, where it creates a
    QApplication instance. As Qt can receive arguments from the command line,
    you can pass any arguments to the QApplication object. Usually, you do not
    need to pass any arguments, and you can use the following approach:

    \badcode
    if __name__ == "__main__":
        app = QApplication([])
    \endcode

    Next, the wizard instantiates the \c MainWindow class and shows it:

    \badcode
        window = MyWidget()
        window.show()
        ...
    \endcode

    Finally, the wizard calls the \c app.exec_() method to enter the Qt
    main loop and start executing the Qt code:

    \badcode
        sys.exit(app.exec_())
    \endcode

    Open the .ui file in the Design mode to create a widget-based UI in \QD.

    The \uicontrol Window wizard adds similar code to the source file, without
    the UI bits.

    The \uicontrol Empty wizard adds similar code to the source file, but it
    does not add any classes, so you need to add and instantiate them yourself.

    For more information about the
    \uicontrol {Qt for Python - Qt Quick Application - Empty} wizard, see
    \l {Creating Qt Quick Based Python Applications}.

    For examples of creating Qt for Python applications, see
    \l {https://doc.qt.io/qtforpython/tutorials/index.html}
    {Qt for Python Examples and Tutorials}.

//! [python project wizards]


//! [python qml project wizards]

   \section1 Creating Qt Quick Based Python Applications

    The \uicontrol {Qt for Python - Qt Quick Application - Empty} wizard enables
    you to create a Python project that contains a main QML file. Specify the
    minimum PySide version to run the application.

    \image qtcreator-python-wizard-qml.png

    The wizard adds the following imports to the source file to provide access
    to QGuiApplication and QQmlApplicationEngine:

    \badcode
    import sys
    import os

    from PySide2.QtGui import QGuiApplication
    from PySide2.QtQml import QQmlApplicationEngine

    \endcode

    The wizard also adds a main function, where it creates a QGuiApplication
    instance and passes system arguments to the QGuiApplication object:

    \badcode
    if __name__ == "__main__":
        app = QGuiApplication(sys.argv)
    ...
    \endcode

    The following lines in the main class create a QQmlApplicationEngine
    instance and load the generated QML file to the engine object:

    \badcode
        engine = QQmlApplicationEngine()
        engine.load(os.path.join(os.path.dirname(__file__), "main.qml"))
    \endcode

    Finally, the wizard adds code that checks whether the file was successfully
    loaded. If loading the file fails, the application exits with an error code.
    If loading succeeds, the wizard calls the \c app.exec_() method to enter the
    Qt main loop and start executing the Qt code:

    \badcode
    if not engine.rootObjects():
        sys.exit(-1)
    sys.exit(app.exec_())
    \endcode

    Open the .qml file in the Design mode to design a Qt Quick UI in \QMLD.

//! [python qml project wizards]
*/