Localized Object Actions

Examples: Context:  The artifact contains multiple real or virtual objects, such as files, or CDs, or car windows.  This often happens in Control Panel, WYSIWYG Editor, and Composed Command.

Problem:  How should artifact present the actions that may be taken on those objects?

Forces:

Solution:  Group object actions together, even more so than for Convenient Environment Actions, and spatially localize them to the object.  Separate them visually from any other kinds of actions, to avoid potential confusion. If there are actions that aren't done via buttons or other obvious visual controls -- drag-and-drop or keyboard manipulation, for instance -- make sure that there is some indication, somewhere, that they exist! (Sometimes, as with dragging objects in a WYSIWYG Editor, there is no need, since we "know" those actions exist, culturally and instinctively. If in doubt, test with your users.)

Resulting Context:  As with Convenient Enviroment Actions, use Disabled Irrelevant Things when needed.  If your users may need to perform one action on several objects at one time, then use Actions for Multiple Objects, keeping in mind that it may make the artifact a little bit more complex.

Notes:  In desktop GUIs, users can sometimes infer which buttons on a panel are object actions and which are environment actions by watching how the actions enable and disable as they select and deselect objects. It works, but it's not a great solution, since its success depends upon (1) the users' willingness to change the selection set, (2) how alert they are to the state changes, and (3) whether they can even make an empty selection set to cause the disabling!  (You can't with some container-type widgets, such as some list box implementations.) Again, separate the two classes of actions; and if you have space, reword the object actions to make it obvious that they refer to the selected objects.

As with environment actions, convention is strong in this area. Recent desktop-GUI software has really picked up on the popup menu, which is an excellent application of this pattern. Perhaps we can extend the idea by making it not just a column of verbal commands, but a popup "card" with pictures, visual cues, and interesting 2D layout...
 


Comments to:  jtidwell@alum.mit.edu
Last modified May 17, 1999

Copyright (c) 1999 by Jenifer Tidwell.  All rights reserved.