Never. Only the viewfinder. It has an indicator. 

"> o < "

">" means your focus point is in front of your subject. 
"o" means you're locked.
"<" means your focus point is behind your subject. 

The non cross type AF sensors (near the edge of the AF groups) aren't as good as the central ones. This causes a phenomena known as "front focusing" or "back focusing" - where the focus is only just out, but makes a massive difference in the image.