Question

I have two toggle buttons that I want to link together so that pressing one releases the other one. So my signals look like this

def on_btn1_tgl_clicked(self, widget, data=None):
    toggled = not self.btn2_toggle.get_active()
    self.btn2_toggle.set_active(toggled)

def on_btn2_tgl_clicked(self, widget, data=None):
    toggled = not self.btn1_toggle.get_active()
    self.btn1_toggle.set_active(toggled)

This seems to work just as I expect, except that when I run the code I get this error

Error in sys.excepthook:

RuntimeError

Original exception was:

RuntimeError

The buttons work fine and nothing crashes, but I don’t know why I’m getting the error, or what it means. If I don’t link the buttons I don’t get any errors.

Does anyone know how to fix this?

Answer 1

When I run your code, I get this exception :

RuntimeError: maximum recursion depth exceeded and the buttons doesn’t work.

My explication is :

1. When you click on button 1, it emit the toggled signal and execute your on_btn1_tgl_clicked() method.

2. In this method, you use gtk.ToggleButton.set_active() which emit a toggled signal too that call your on_btn2_tg1_clicked() method which emit also a toggled signal.

   So, we enter in infinite loop. That’s why the exception is raised.