Why menu doesn't show up from QAction added to QToolBar in PyQt6?

q&a
,
1

The following code shows up the QMenu on clicking the QToolButton in pyqt5. But not in Pyqt6. Is this an behavioral change in Qt6 ? I could not find anything in the documentation.

import sys

from qtpy.QtWidgets import (QApplication, QAction, QMenu, QWidget,
                            QVBoxLayout, QToolBar)


class Widget(QWidget):
    def __init__(self, parent=None):
        super().__init__(parent=parent)
        layout = QVBoxLayout(self)
        toolbar = QToolBar(parent=self)

        menu = QMenu()
        menu.addAction('one')
        menu.addAction('two')
        menu.addAction('three')

        action = QAction( "Number", self)
        action.setMenu(menu)
        toolbar.addAction(action)

        layout.addWidget(toolbar)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    icons.init()
    wid = Widget()
    wid.show()
    sys.exit(app.exec())
2

This is no longer an issue when the QMenu gets a correct parent.

QMenu doesn't show up from QAction addded to QToolBar in Qt6. | Qt Forum.