New Usable Item? (drinking)

[dnk 13]

I want to take an item (can_small) and make it so that the player can pick up the can and have it placed into inventory, and then have it permit him to drink the can and have it removed from inventory.

Is there a tutorial or something on how to do this? So far, my mod looks like this: a config.bin with (will worry about icon later):

class CfgMagazines {
class Can_small : Small_items {
	scope = public;
	model = "\ca\misc\Plechovka_1";
	displayName = $STR_DN_CAN_SMALL;
	picture = "\Ca\weapons\Data\Equip\m_40mmHPgreen_CA.paa";
};
};

And there's this I can use:

this addAction ["Pick Up","drink\pickup.sqf"];

With pickup.sqf being

player addMagazine "can_small"; player addaction ["Drink","drink.sqf"];

But how do I make it so that having the can in inventory allows the player an ability like "drinking" (eg, "use bandage" from ACE) where it is only applicable when the player has that thing in his inventory?

How do I attach this addAction 'pickup' to every can that is placed on the map or dropped from inventory onto the ground?