Option to hide dice roll then reveal? (for both DM/player)

Quite new to Roll20 so apologies if this is a silly question.  Looking to run a gambling den next session. The game I have in mind involves the PC and myself (DM) rolling a few dice in secret, and then revealing to see who has the higher number. I know GMs can hide their rolls, but is there an option for the PC to do it? And more importantly, an option for both to then reveal the rolls just made?  Thank you! 

Roll20 doesnt really support this directly. The best way to handle it would be by setting up a card deck with dice images. Instead of rolling dice, draw a number of cards, and then play them ti the desktop to reveal them. You can set up a card deck as "Infinite" - this means that they work like dice, in that there are no limits on how many of each you can draw, and you have an equal chance for each result no matter how many you have drawn. You still need to shuffle the deck once, before use, but after that it'll do what you want.