It is probably along the same lines as my 2008 Megane GT - that is also keyless, it works with one of those credit card sized fobs, which you slot into the dash and then press the "engine start/stop" button to start or switch off the engine.
The fob does not have to be in the dashboard slot; if you have the fob in a pocket (or about your person) when you approach the car, it detects the presence of the fob and unlocks all doors and allows you to start the engine without taking the key out of your pocket - as long as it remains within the car's detection area.
When exiting the vehicle, whether or not the fob is in the dash, you just press the "engine start/stop" button which stops the engine running. Opening the driver's door then switches off all the electrics, and you use the "lock" button on the fob to activate the central locking once you've closed the door behind you. You cannot even lock the fob in the car (if you accidentally leave it in the dash) as there is no way to lock the car from the outside without having the fob in your hand.
HTH.