Why can’t python seem to find the InterfaceWithNoMenu class
class Settings(Screen):
class SettingsWithNoMenu(kivy.uix.settings.SettingsWithNoMenu):
def __init__(self, *args, **kwargs):
self.interface_cls = InterfaceWithNoMenu
kivy.uix.settings.SettingsWithNoMenu.__init__( self, *args, **kwargs )
class InterfaceWithNoMenu(kivy.uix.settings.ContentPanel):
def add_widget(self, widget):
if self.container is not None and len(self.container.children) > 0:
raise Exception(
'ContentNoMenu cannot accept more than one settings panel')
super(InterfaceWithNoMenu, self).add_widget(widget)
kivy.uix.settings.InterfaceWithNoMenu.__init__( self, *args, **kwargs )
actionview = ObjectProperty(None)
settings_content = ObjectProperty(None)
def __init__(self, **kwargs):
super(Settings, self).__init__(**kwargs)
...
I’m trying to change the look/feel/behaviour of the Settings module in a kivy-based python GUI app.
Unfortunately, when I create a settings window with the above program that creates an instance of the locally-overridden self.SettingsWithNoMenu class, I get the following error:
self.interface_cls = InterfaceWithNoMenu
NameError: name 'InterfaceWithNoMenu' is not defined
I don’t understand. It’s right there. I mean, the class InterfaceWithNoMenu is literally defined right underneath the one (SettingsWithNoMenu) that’s referencing it.
Why can’t the class SettingsWithNoMenu find InterfaceWithNoMenu? Why am I getting a NameError here?
>Solution :
InterfaceWithNoMenu is defined in the namespace of the Settings class, not the global or local namespace. You should be able to do:
self.interface_cls = Settings.InterfaceWithNoMenu
since Settings is available in the global namespace.
Nested class definitions are a little awkward IMO and I would usually recommend not using them, especially if there’s a dependency between "sibling" classes like this that requires the nested class to access its enclosing class.