RequiredIf<T>.condition constructor
Creates a new instance of the RequiredIf validation rule based on a condition.
condition
: The condition function that determines if the value is required (required).message
: A custom validation message (optional) to be displayed when the validation fails.
Implementation
RequiredIf.condition(this.condition, {String? message})
: otherFieldName = null,
equalTo = null,
super(message);