cargo shorts are no good, especially the ones with big ballon type cargo pockets. I prefer shorts that have either the 'painter style pocket on the right leg or just a traditional 4 pocket (or 5 if you count the little change pocket), baring that there is a hybrid type cargo which has one FLAT unobtrusive "cargo" pocket....those are fine as well. Shorts also need a gusseted crotch so as not to cut yer boys circulation off and the should fall just at the knees for daily wear in public. You don't need knickers (this is not 2011 anymore) and NOBODY needs skinny hipster shorts that fall at your thighs.
If you are lounging around the house some 7 or 8 inch shorts can be good in the dead of summer or if you're running then some 8 or 9 inch shorts are preferred.
Casual out and about shorts in public for men shorter than 8 inches in public are unacceptable. Longer than 12 should only be allowed at a Limp Bizkit concert or a Gathering of the Juggalos festival.