[FIXED] In a QMenu, how to make a submenu callable like a QAction

Issue

I am trying to implement something like a classification tree, in which I right-click a row in QTableWidget to call a Menu, then I choose a class label for it. My label tree is like this:

• Class A

  • Class A1

  • Class A2

    • Class A3

• Class B

Here Class A, Class A2 are obviously added through QMenu.addMenu() method, in which they are not callable. Class A1, Class A3, and Class B are added through QMenu.addAction() method and they are callable. So I am wondering is there any way to make a submenu callable like a QAction that can be triggered? Or are there any better ways to achieve my design purpose?

btw I think aboutToShow() signal does not work, since the signal is emitted when the submenu shows up instead of being clicked.

Code:

class ClassMenu(QMenu):

    def __init__(self):
        
        super(ClassMenu, self).__init__()
        class_A = self.addMenu("ClassA")
        class_A1 = class_A.addAction("ClassA1")
        class_A2 = class_A.addMenu("ClassA2")
        class_A3 = class_A2.addAction("ClassA3")
        class_B = self.addAction("ClassB")
        
        class_A1.triggered.connect(self.onMenuClicked)
        class_A3.triggered.connect(self.onMenuClicked)
        class_B.triggered.connect(self.onMenuClicked)

    def onMenuClicked(self):
        print(self.sender().text())

Solution

A possible solution is to override mousePressEvent and verify that the QAction associated with the position has a QMenu associated with it:

from PyQt5.QtWidgets import QApplication, QMenu


class ClassMenu(QMenu):
    def __init__(self):
        super(ClassMenu, self).__init__()
        class_A = self.addMenu("ClassA")
        class_A1 = class_A.addAction("ClassA1")
        class_A2 = class_A.addMenu("ClassA2")
        class_A3 = class_A2.addAction("ClassA3")
        class_B = self.addAction("ClassB")

        class_A1.triggered.connect(self.onActionClicked)
        class_A3.triggered.connect(self.onActionClicked)
        class_B.triggered.connect(self.onActionClicked)

        print(class_A.menuAction())

    def onActionClicked(self):
        print(self.sender().text())

    def onMenuClicked(self, menu):
        print(menu.title())

    def mousePressEvent(self, event):
        super().mousePressEvent(event)
        action = self.actionAt(event.pos())
        if not action:
            return
        menu = action.menu()
        if menu:
            self.onMenuClicked(menu)


def main():
    app = QApplication([])
    menu = ClassMenu()
    menu.move(100, 100)
    menu.exec_()


if __name__ == "__main__":
    main()

Answered By - eyllanesc