Re: GtkColorPickerButton

[Havoc Pennington <hp redhat com>]

On Tue, Mar 18, 2003 at 10:06:06AM -0500, Jody Goldberg wrote: 
> To palette or not to palette that is the question.
> Can we get a show of hands ?

Not really the way to go about it - 

 1. what are the tasks that the user will perform 
    with the widget(s)?

 2. what tasks do these widgets make most visible/efficient?

 3. which one(s) is therefore best for the tasks that users want to
    do?

As I remember it, it seems to me that the combo is optimized for
quickly applying a set of colors. i.e. it is an "apply color" button,
that can be simply clicked one time to apply its current color to some
object, such as a range of cells. It also has the dropdown to change
the current color.  The dropdown is optimized for the case where you
are using the same set of colors repeatedly (a palette).

So this widget seems to support these tasks:

 1. apply the same color you applied last time (2 steps, 
    select object to apply to, click the combo)

 2. apply a color you applied recently (4 steps, select, click, drag,
    release/click)
 
 3. apply a whole new color (6-7 steps plus some conceptual thought,
    click, open dialog, click color, close dialog, choose the custom
    entry you've created)

We would use this widget if we feel that applying the same colors over
and over will be the most frequent task by far.

The color picker button on the other hand is for picking one color out
of the set of all possible colors (well, we could also enable the
palette in the dialog that it pops up). But basically it supports this 
task:

 1. selecting an active color for some object (3 steps, 
    click picker button to open dialog, pick color, close dialog)

The color picker button does not support the task of *applying* a
color to an object selected elsewhere; it only supports *selecting*
the current color for an object. i.e. the currently-displayed color of
the colorcombo is the last color you applied, the currently-displayed
color of the picker button is the current color of the object being
affected.


In any case, there are rigorous ways to go about these UI questions,
it's not something we need to just make up.  This is why the Isaacs
and Walendowski book is so handy, it gives you concrete ways to go
about answering this sort of question.


The two widgets make different tasks highly visible, and different
tasks highly efficient (minimum number of steps), and in any given 
context the highly visible/efficient tasks should be the ones we
expect most people to be doing most often.


FWIW it seems likely to me that both widgets are useful in their own
contexts; the color picker button is good for say the gnome-panel or
gnome-terminal color preferences, where you are likely to want to
carefully pick an exact color rather than using palette presets, and
you're only picking a color one time. And the combo is right for
color-coding spreadsheet cells where you apply the same colors over
and over.

If you try to use the picker button for the spreadsheet, it will suck 
because the common case will take 3-4 user steps instead of 2.

If you try to use the color combo for the gnome-panel prefs, it will 
suck because the common case will take 6-7 steps plus some complexity, 
instead of 3-4 simple steps.


So based on that argument, I would include both widgets.  But some
nice docs on when to use each wouldn't hurt.

Havoc