Thank's Aren,
This solution work fine, but i have a problem.
When I'm editing text, and text row length became greater than scrollView width, i need a system that automatically scroll horizontal scrollBar up to caret position.
I thought to force horizontal.value =1 after onChange event, but it works only if append text.
Solution could be know the localPosition of caret, ad tell to ScrollView to scroll at this position,if position is not in the scrollView bounds.If that is the right way, what I have to do to know caret localPosition?.