Our form works, and both the director and data entry personnel are thrilled with the form design, but we're not ready for production yet! Our form doesn't yet perform the promised task of preventing or discouraging user errors. Number boxes still allow letters, combo boxes aren't limited to the choices given, and dates have to be filled in by hand. In this chapter, we're going to cover the following topics:
- Deciding on the best approach for validating user input
- Learning how to use Tkinter's validation system
- Creating custom widgets for our form that validate entered data
- Automating default values where appropriate in our form
Let's get started!