Hi,
Get the book "An Easy Reference for ALV Grid Control" http://scn.sap.com/docs/DOC-10353
In the book:
– Inserting an inner table to store cell display styles
see program BCALV_EDIT_02 .
cl_gui_alv_grid=>mc_style_disabled and cl_gui_alv_grid=>mc_style_enabled
Also http://wiki.scn.sap.com/wiki/pages/viewpage.action?pageId=37199
Regards.