Self validating textbox
All other options are passed on to the Entry widget itself.
Note: Newer versions of Tkinter support validate and validatecommand options that can be used instead of the extra variable. The first two examples are subclasses that check that the input is a valid Python integer or float, respectively.
Instead, they will process the values and save them back to the attributes being validated.
This is because the same validator will run for each attribute (3 times in total) and we only need to run it once for the whole attribute set.
If an attribute fails the validation, call yii\base\Model::add Error() to save the error message in the model, like you do with inline validators.
For example, the inline validator above could be moved into new components/validators/Country Validator class.If you want to make sure a rule is always applied, you may configure the skip On Empty and/or skip On Error properties to be A standalone validator is a class extending yii\validators\Validator or its child class.You may implement its validation logic by overriding the yii\validators\Validator::validate Attribute() method.]]