Question

I try to add a function in a PyQt class, but it always returns me an error.

# Error: TypeError: connect() slot argument should be a callable or a signal, not 'NoneType' # 

def commander (self, arg):
    exec arg    

def aButton (self, layout, **kwargs):
    name = kwargs.pop("name","Button")
    command = kwargs.pop("command", "" )
    button = QtGui.QPushButton(name)
    button.clicked.connect(self.commander(command))
    layout.addWidget(button)
    return button

May be someone here can help me to solve that :’)
Thx !

Answer 1

You need a function:

button.clicked.connect(lambda: self.commander(command))

Note the lambda will avoid the evaluation of the function call, so it’ll call self.commander(command) only when clicked