I have got difficult form in yii2 view, where some fields show or hide. It decide from user field choises, select options in the form. I write this frontend logic with custom jq
To remove a field from validation:
$('#yourFormID').yiiActiveForm('remove', 'yourinputID');
To add a field to validation list:
$('#yourFormID').yiiActiveForm('add', {
id: 'country',
name: 'yourinputID',
container: '.field-inputID', //or your cllass container
input: '#yourinputID',
error: '.help-block', //or your class error
validate: function (attribute, value, messages, deferred, $form) {
yii.validation.required(value, messages, {message: "Validation Message Here"});
}
});
And don't forget conditional validation in your model. More info