[IxDA Discuss] select exact number widget?

[Jeff Howard]

Hi Victor, 

Two things come to mind. 

In Tog on Interface, Bruce Tognazzini wrote about the development of
an idiom in-between checkboxes and radio buttons. Essentially an "at
least one but perhaps more than one" set of checkboxes. When you
deselected the last checkbox, it bumped the selection over to the
next checkbox. This works well for enforcing a minimum number, but
doesn't seem quite as good for restricting the maximum (though the
shifting idea could work there too).

What might be a better mapping in this case is something like what
John Schrag mentions. Think of how the Illustrator gradient palette
works. You need to select two colors, one for either end of the
gradient. The palette begins with an arrow on either end of a
continuum of colors. Those arrows always point to exactly two colors
(forget for a moment that you can add more arrows) and you can drag
either or both arrows to different values. In your example, imagine
the apples are in a row. Two arrows are beneath the apples. You
simply slide the two arrows left or right to point to the two apples
you want and enforce exclusive selection. Two apples would be
selected by default at the beginning, or there could be an empty
space to "park" the arrows.

// jeff