One of the very basic principles for laying out interactive interfaces is what I call: “The Handle and the Suitcase Rule”. The reason we know that the handle belongs to the suitcase and we can carry the suitcase with it is so simple it really seems kind of pointless mentioning it: It is attached to the suitcase.
Translated to an interface, that means that any control should be adjacent or otherwise visually associated with the object that the control manipulates. When viewed in the light of a physical suitcase and the handle this seems like a no-brainer but it is astonishing how often this simple rule is ignored when it comes to designing software interfaces. In the next post I will show some examples of controls that are detached from their object and how to use layout, color, and other graphical elements to create an association.