Now, let's apply the mixin class to the DateEntry class we made before, keeping the same validation algorithm as follows:
class DateEntry(ValidatedMixin, ttk.Entry): def _key_validate(self, action, index, char, **kwargs): valid = True if action == '0': valid = True elif index in ('0', '1', '2', '3', '5', '6', '8', '9'): valid = char.isdigit() elif index in ('4', '7'): valid = char == '-' else: valid = False return valid def _focusout_validate(self, event): valid = True if not self.get(): self.error.set('A value is required') valid = False try: datetime.strptime(self.get(), '%Y-%m-%d') except ValueError: self.error.set('Invalid date') valid = False return valid
Again, pretty simple, all we need to do is specify the validation ...
