May 2018
Beginner to intermediate
452 pages
11h 26m
English
All of our fields are required, so let's start with a basic Entry widget that requires data. We can use these for fields: Technician and Seed sample.
Add the following code under the ValidatedMixin class:
class RequiredEntry(ValidatedMixin, ttk.Entry):
def _focusout_validate(self, event):
valid = True
if not self.get():
valid = False
self.error.set('A value is required')
return valid
There's no keystroke validation to do here, so we just need to create _focusout_validate(). If the entered value is empty, we just set an error string and return False.
That's all there is to it!