Note: @old_value field of #AtkPropertyValues will not contain a valid value. This is a field defined with the purpose of contain the previous value of the property, but is not used anymore.
Get field newValue.
Get field oldValue.
Get field propertyName.
Set field propertyName.
Note: @old_value field of #AtkPropertyValues will not contain a valid value. This is a field defined with the purpose of contain the previous value of the property, but is not used anymore.