How to initilize a field in a form when all records in the grid are deleted

You can use this

public void delete()

{

    super();

    if (!Thy_InventItemPrintParameters::exist(Thy_InventItemPrintParameters.ItemId))

    {

        InventFamilyId1.text("");

        InventFamilyId1.enabled(Noyes::Yes);

        InventFamilyId1.mandatory(Noyes::Yes);

    }

}