i have an entity "complaints",which has 1:n relationship with another entity "Actions",entity form "complaints" has subgrid with child records of "Actions".If records in subgrid is equal to 5 ,the form should become

i have an entity "complaints",which has 1:n relationship with another entity "Actions",entity form "complaints" has subgrid with child records of "Actions" associated in it.If records in sub grid is equal to 5 ,the form should become read only.i can make record read only by deactivating the record.is there any other way of doing it so that the record stays active and read only?.can it be done by using out of the box feature other than javascript?