On Nov 5, 12:05 pm, "Sean Catchpole" <[EMAIL PROTECTED]> wrote: > Is there a good reason why placing scripts at the bottom of a page is > a bad idea?
wow I was about to come here and post the same thing. I have a blog post about this: http://michaelshadle.com/2007/10/30/handling-events-pre-documentready-in-jquery/ Basically I am trying to align with the Yahoo concepts too, but placing jQuery at the bottom has some odd behaviors. Even with stuff chained to $(document.ready(), I have events that are bound inside of that but inside of the callbacks on the events I can raise a "$ is not defined" and "jQuery is not defined" somehow. Somehow, the jQuery code is being called, because it is executing the $(document) stuff, but it still hasn't bound all the items in the DOM or assigned them to the jQuery global object or the $ object or something. Here's one example of that. You need Firefox. I am using Firefox 2.0.0.9 with Firebug and Yslow, just FYI. http://mikehost.com/~mike/tmp/jquery/jquery1.html If you click on one of the links, while it's loading that page if your mouse moves over the other one it will raise the Javascript warning... Also any <a href="javascript:foo()"> links that call jQuery related stuff can't be clicked before jQuery is fully loaded. Having the script towards the bottom can also mess that up. In my blog post I wound up using an ID and a callback so it can only work if jquery is loaded, however, it winds up acting like a dead link until everything is loaded fully (extremely poor user experience) and actually stays dead a lot of the time (for reasons unknown to me) - I've also tried $ (window).load() and some other stuff. For the mouseovers, I might be able to do some if ($ && typeof $.isReady == 'boolean' && $.isReady) or something to check for the existence of $ ... but the question still remains for more things. Maybe John monitors this list or another hardcore Javascript guy and could chime in.... Can jQuery be put at the bottom of the page safely, or is using jQuery with Yahoo JS optimization tips mutually exclusive? And if so, I guess the fix is to include jquery in the <head> (as soon as possible) and the rest can still be in the footer...
