[Sigia-l] Re: HTML Multiple Select Widget

[Sanchez, Mario]

A few features of multiple-select scrolling boxes:
1. They hide most of the options, especially on very long lists -
therefore they may be inappropriate if users need to quickly scan lists
that aren't organized in an obvious & predictable way.
2. They hide the selected options, especially on very long lists -
therefore they may be inappropriate when the user needs to return to the
list often to edit it.
3. They require combination keystrokes to select, and incorrect
keystrokes can easily deselect previous selections - therefore they may
be more likely to result in human error in making / editing selections.
4. They use up relatively little real estate - therefore they may be
appropriate when screen space is limited.

Other widgets that allow multiple selections;

- List(s) of checkboxes - like http://www.epitonic.com/radio.jsp 
Expose options and selections, and are simpler to select/deselect (1,2,3
above), but use up much more real estate.

- A combination of 2 scrolling boxes with command-buttons between. One
list is available options, the other list are selected options, and the
command buttons allow you to move items from the "available" to the
"selected" list. This exposes the selected options more than the single
scrolling list, and still uses up less real estate than ckeckbox lists,
but the interaction is still more complex than the checkbox list.

See http://www-106.ibm.com/developerworks/web/library/us-widget/ for a
decent library of widgets.

Hope that helps,
Mario Sanchez
Fisher Scientific