What's the rule of thumb if I want to change observed object's single property from different menu items (think - list of options).
E.g. I have an app that displays a car in a single window. I have a menu with menu item that says [Colors] with few submenu items like [Black, Green, Blue, Red, White, etc.]. How do I implement the mechanism behind this so that each submenu item changes same property (in this case - color) to different values.