Not editable fields in Page

Hi

I would like to ask You one very begging question: 

How can I provide when I run some page from table/codeunit .. some fields (not all) to be Not Editable. I can't set property of that  Editable=False , because in different circumstances-> different fields should be not Editable. What function should be used after runing the page

                        ItemPage.SETTABLEVIEW(Item);

                        ItemPage.SETRECORD(Item);

                        ItemPage.RUNMODAL;

I tried with:    Page.Field.EDITTABLE(False), but it seems it is not possible use EDITABLE function only for filed or this is not right way for using it

Thanks in Advance