Item icon in interactive area

I've grown accustomed to the practice of making the icon for the inventory object "light up" when entering an area in which it can interact. That is, if you have a knife in inventory, and a grapefuit on a table, the knife icon changes while touching upon the grapefruit before a left click cuts it in half. The same thing applies if both the knife and the grapefruit already are in inventory.

I'm sure there is a way to do this in Visionaire, but I can't seem to figure it out with my lousy programming skills. I was looking for something like an execution type called "item enters object area" under object actions, and was hoping to be able to switch cursor in the action part or something like that, but no such luck. And anyway, that wouldn't affect the object cursor when it entered the area of another object in inventory that it can be combined with.

I'm thankful for any help on the subject!