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Please review the following information to ensure ** the GNU Free Documentation License version 1.3 requirements ** will be met: https://www.gnu.org/licenses/fdl-1.3.html. ** ****************************************************************************/ /*! //! [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] */