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The Polite Interface or Guidelines for Dialogs

Dear Tog,

I have a suggestion for a design rule which I have not found among yours. It has to do with programs which compete for the users attention. Countless times have I been interrupted when writing (or clicking, or ...) by a program that springs to the front and gets focus just to tell me that it has started or that it is finished with a task. Sure, sometimes I would like to be noticed but not by losing focus on my current work. The time to get going again is usually not very long but in most cases totally unnecessary.

The rule could be named "know your place" or "don't interrupt the user". The problem is related to what you've written about doing things in the background when possible but I think it worth a rule of it's own.

Any suggestions of how to follow my rule in the best way? Maybe to tell me when I've stopped typing and stopped moving the mouse?

And please don't tell me that I should use another OS because most of us haven't got that option. ;-)

Best regards, Par
--- Par Olsson, Icon Medialab

You didn't tell me what OS you are using, but since you said you don't have the option to change, we will assume it's Windows. However, it really doesn't matter what OS it is, as long as it really is an OS, rather than, say, pure HTML. You have the power to do the right thing.

And the right thing, folks, as Par pointed out, is to know our place.

Errors, status updates, and all manner of messaging can be a lot more subtle than most of us have been making them. Consider these principles in making your design decisions:

  1. Do not interrupt the user with a modal dialog unless the user would not otherwise be able to continue with their present task without taking some immediate action—Par's Law.

  2. Do offer users appropriately-scaled feedback in ways that don't interrupt.

    For example, let's say you have made a search at the user's request and now have a result to report. Let's say that that search filled in a single field on the user's current form, such as the address of the person to whom you will send it, garnered from your address book. Instead of blaring out your success, fill in the field. If further feedback is useful, then blink an amber icon of some sort while you are searching for the address, then change it to green if successful, red if not. If its a long form, and the user may now be on a different section, display a status indicator for the whole form somewhere, showing the overall status. The status indicator, in iconic form, might carry the meaning, "somewhere on this form a field is red. Click to find it." When users finished with the form and see only green, they'll know it is safe to continue.

  3. Use auto-timeout dialogs where appropriate.

    For example, print dialogs ask the user how many copies they want to print, etc. Then they sit there for the next three days waiting for an answer. If the user hasn't answered within two minutes, assume the user isn't going to answer. The user has left for lunch, forgetting that this stupid dialog is going to come up and expecting to find their 500 page document printed when they return. Take a chance! Make a wild guess that the user wants one copy! When the two minute time-out is up, go ahead and print! Even if it were that one time in a million when the user wanted two copies, he or she can always print out another. Even more likely, he or she will move to the nearest copier and make one. Either way, no time is lost and time will likely be saved.

Those of you who have seen the Starfire film have probably noticed a dialog box that pops up in front of Julie that says, "Verbal command not recognized." Within a couple of seconds, it disappears. How does it know to do that? The system watches her eyes, and when it sees she has read the message, it removes the message.

We are still a ways away from that (even though all the necessary technology is here). In the meantime, think of your messages as coming from a valued assistant. Make them polite, make them useful and responsive, and scale them to the level of interruption necessary.


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