Modes
Addressed in Saffer, pp. 111 - 114
- Saffer's definition: A mode is a fork in the rules.
- Raskin's definition: A human-machine interface is modal with respect to a given gesture when (1) the current state of the interface is not the user's locus of attention and (2) the interface will execute one among several different possible responses to the gesture, depending on the system's current state.
- Differences among modes, quasi-modes (spring-loaded modes) and one-off modes (temporary modes).
Examples
- Insert/replace mode for text editing
- Volume control buttons on the iPhone
- Time setting buttons on an alarm clock
Discussion questions
- Do ATM buttons with screen-based labels produce modal interaction?
- What design considerations will avoid modes?
- Do one-off modes cause usability problems?