This function returns a parent value from a Schema view. This is needed before generating the dependent option list for the current field.
In most cases this function returns the same value as the internal parent value parameter because most option lists trigger their dependency on the unique key for the parent field. However, this is not a requirement for complex dependent choice lists.
Takes four parameters:
The name of the schema view used for the current field.
The name of the schema relation between this field and the parent field.
The name of the parent field.
The internal value for the parent field. This may be different than the value displayed on the page. This is often a unique number stored internally.
<$parentValue=getParentValue("xState", "Country_State", "xCountry", "123")$>