PyQt: inheriting from PushButton

Question

I'm working on an existing project and I have very little experience with PyQt so I'm not sure what I would need to produce a minimal working example here, maybe someone can help me out anyways.

There is a part in the code where a QPushButton is created and added to a QGraphicsScene, like this:

b = QPushButton('foo')
scene.addWidget(b)

I'd like to replace b with a class inheriting from QPushButton, something like:

class Bar(QPushButton):
    def __init__(self):
        super(Bar, self).__init__('foo')

I believe that the following should then behave identical to the first code sample:

b = Bar()
scene.addWidget(b)

Instead the code crashes here and I have so far not been able to figure out why. Is there something obvious I'm doing wrong?

Answer 1

Try it:

class Bar(QPushButton):
    def __init__(self, button):
        super(Bar, self).__init__()
        self.setText(button)
        self.clicked.connect(lambda: print("Press button"))

class Desktop(QMainWindow):
    def __init__(self):
        super(Desktop, self).__init__()
        self.centerWidget = QWidget(self)
        layout            = QVBoxLayout() 
        scene = QGraphicsScene()  
        view  = QGraphicsView(scene)

        b = Bar("Press me :)")

        scene.addWidget(b)
        layout.addWidget(view)
        self.centerWidget.setLayout(layout)
        self.setCentralWidget(self.centerWidget)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex  = Desktop()
    ex.show()
    sys.exit(app.exec_())