ALV dynamic field type at runtime

Hi friends.

When I change field A value, I want to set the field B type and its check table, at runtime and only to the B cell, current line.

Is it possible ?

e.g.:

ALV

colums A, B

New line 1:

user enters a value to field A. During its on_datacheck I want to set input help mode to Cell B( to line 1 only) Dictionary Search Help and set the Determined Input Help.

So user can after that, choose an value using new determined input help.

After that. New on_datacheck happens to cell B(line 1) and happens table checking and show automatic error.

Is it possible ?

thanks in advance.

Glauco