StacktraceTop: g_type_check_instance_cast (type_instance=0xb6c07b48, widget_notify_cb (widget=0xb6c07b48, pspec=0xa00dd40, ?? ()
StacktraceTop: check_instance_ cast (type_instance= 0xb6c07b48,
g_type_
widget_notify_cb (widget=0xb6c07b48, pspec=0xa00dd40,
?? ()