Progress bars

[Richard Gaskin]

Bill wrote:
> That is such a nice explanation and example for a progress bar. I wish the
> text files I imported were big enough so I could use it. The only thing that
> takes a long time in my stacks is opening them when the MySql is first
> accessing and whenever you refresh the MySql connection.
> 
> Do you have any idea how to get some numbers from that lengthy MySQL process
> so that I can use your progress bar code for that because it sometimes looks
> like the program has crashed when it is doing the MySQL load.

That sounds like a problem with the connection.  Hopefully one of the 
other folks here who've worked through MySQL anomalies may be able to 
shorten the connection time.

In general, when a progress bar is displayed for an activity comprised 
of an unknown number of steps, the OS uses a different appearance for 
the scrollbar to indicate that. On Mac OS, for example, it uses what 
they call a "barber poll" effect.

Rev doesn't currently have this built in so I just filed a request for 
it, to allow a new token of "unknown" to be used for the endValue of a 
scrollbar of style "progress" to indicate that it should use the OS' 
method of drawing a progress bar of an unknown number of steps:
<http://support.runrev.com/bugdatabase/show_bug.cgi?id=2691>

In your case it may be possible to shorten the connection time so that 
simply displaying something like "Connecting to database..." with a 
watch cursor will buy you the patience needed from your user to complete 
the connection without frustration.

Some studies suggest that the threshold of such patience is around 10 
seconds - from <http://www.useit.com/alertbox/9703a.html>:

   Currently, the minimum goal for response times
   should therefore be to get pages to users in no
   more than ten seconds, since that's the limit
   of people's ability to keep their attention
   focused while waiting.

MySQL has a good reputation for being optimized for performance, so it 
seems reasonable that one should be able to do most queries to a MySQL 
database in under 10 seconds.  Perhaps if you can post the portion of 
code causing the delay someone here may be able to help trim the wait time.

PS:  If the UseIt.com link seems a good read to you, you might enjoy 
some of the other usability links on the right side of my Resources page:
<http://www.fourthworld.com/resources/index.html>

I'm particularly fond of the articles at UIE.com.

--
  Richard Gaskin
  Fourth World Media Corporation
  __________________________________________________
  Rev tools and more: http://www.fourthworld.com/rev