Guys, do you purposely try to knock/trip/bump into a particular girl sometimes just to flirt/touch her?

I've noticed how this guy I like bumps into me a lot...kinda doesn't seem like a coincidence he always says sorry, sometimes he blushes, sometimes he has a worried look like I'm gonna punch him or something for knocking into me...but I really don't mind it because I like him too lol...anyways is it true guys do do these things on purpose?

any other signs to watch out for?