How to change the interval in a setInterval as it is running?

[Simon Wigzell]

I have a slide show that uses setInterval to move through the iamges. I
would like to offer the visitor the option of changing the speed as it is
running. I see an example of this here
http://www.sidney.ca/dynamic/Page125...ageMode=Hybrid but cannot find
the source for it.

I could have it in a form and refresh the page but I would rather do it
dynamically like this example. Any ideas?

[Randy Webb]

Simon Wigzell said the following on 9/2/2007 3:25 PM:

I have a slide show that uses setInterval to move through the iamges. I
would like to offer the visitor the option of changing the speed as it is
running. I see an example of this here
http://www.sidney.ca/dynamic/Page125...ageMode=Hybrid but cannot find
the source for it.

I could have it in a form and refresh the page but I would rather do it
dynamically like this example. Any ideas?

The script is in the page (part of it) and part of it is here:

http://www.sidney.ca/dynamic/cm/webu...s/slideshow.js

To answer your question, you use setTimeout with a variable and change
that variable.

--
Randy
Chance Favors The Prepared Mind
comp.lang.javascript FAQ - http://jibbering.com/faq/index.html
Javascript Best Practices - http://www.JavascriptToolbox.com/bestpractices/

[Thomas 'PointedEars' Lahn]

Simon Wigzell wrote:

I have a slide show that uses setInterval to move through the iamges. I
would like to offer the visitor the option of changing the speed as it is
running.

A) var timeout = window.setTimeout(..., x);
...
window.clearTimeout(timeout);
timeout = window.setTimeout(..., y);

B) var intv = window.setInterval(..., x);
...
window.clearInterval(intv);
intv = window.setInterval(..., y)

Approach B has the advantage of creating a new item only the first time
and when the speed should change; it has the disadvantage of being slightly
less supported and AIUI has a lesser chance of being executed real-time.

I see an example of this here

http://www.sidney.ca/dynamic/Page125...ageMode=Hybrid but cannot find
the source for it.

View Page Source, search for `<script' or, in this case, `javascript:'.

It might also help to http://getfirebug.com/
PointedEars
--
"Use any version of Microsoft Frontpage to create your site. (This won't
prevent people from viewing your source, but no one will want to steal it.)"
-- from <http://www.vortex-webdesign.com/help/hidesource.htm>

[Dr J R Stockton]

In comp.lang.javascript message <u6ECi.116300$rX4.48684@pd7urf2no>, Sun,
2 Sep 2007 19:25:14, Simon Wigzell <si**********@shaw.caposted:

>I have a slide show that uses setInterval to move through the iamges. I
would like to offer the visitor the option of changing the speed as it is
running. I see an example of this here
http://www.sidney.ca/dynamic/Page125...ageMode=Hybrid but cannot find
the source for it.

I could have it in a form and refresh the page but I would rather do it
dynamically like this example. Any ideas?

Clear the timeout without displaying, and start another.

Or use setTimeout or setInterval set to (say) one second as a "wake-up",
and, at each arousal, consult a rate control to see if enough time has
elapsed.

If you can afford to change the rate only after the current wait, just
read the new timeout from a control each time.
It's a good idea to read the newsgroup c.l.j and its FAQ. See below.

--
(c) John Stockton, Surrey, UK. ?@merlyn.demon.co.uk Turnpike v6.05 IE 6
news:comp.lang.javascript FAQ <URL:http://www.jibbering.com/faq/index.html>.
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