When using APEX.jQuery() - Syntax...?

Question

Hi,
I have migrated to Apex 4.02 and had an old jQuery Version running on 3.2.
Now I have learned that I can use the build in jQuery Libs which load not all UI functionality but additional UI components can be loaded from the APEX - Lib.
I have read that APEX renamed its jQuery implementation to APEX.jQuery().
I have thrown away my old jQuery Libs ( only the standard APEX jQuery Libs are loaded ), but my jQuery invokes are still working with $().
So when do I have to use the syntax APEX.jQuery() and why is $() still working...?
Thanks, Juergen

Answer 1

Hi,
I also want to add my 2 cents. See it as recommendation from the APEX development team. :-)
So the question is, when to use jQuery/$ and when to use apex.jQuery? Actually it depends where you use it!
That might at first hand be confusing, especially because as some of you already know, as long as you don't include your own version of jQuery, the JavaScript variables jQuery, $ and apex.jQuery are all the same. So it looks like that it doesn't matter that much, but actually it's very important if you upgrade your application/plug-in to a newer version of APEX.
We try to stay up-to-date with the included version of the jQuery library when we release a new version of APEX. So for APEX 4.1 it's very likely that we include jQuery 1.5. As you can see from the change log of the jQuery project they also sometimes make changes which breaks existing functionality. To minimise your risk when you upgrade to a newer version of APEX you should follow the following recommendations.
JavaScript code in your Application:
If you want to use jQuery in your own JavaScript code in an application we recommend to use jQuery or the shortcut $.
Why:
1) If you upgrade APEX there is the potential that the newer jQuery version breaks your existing code. To avoid intensive testing and rewriting your application to the new jQuery version you can just include the old jQuery library into your page template and you are done. The variables jQuery and $ will point to your own jQuery version and not the one shipped with APEX. No additional code changes necessary. That will help to minimize your risk of upgrading to a newer version of APEX.
2) You need a newer/older version of jQuery in your application because one of the jQuery plugins which you want to use just works with that version. In that case just include the newer/older jQuery library into your page template and the variables jQuery and $ will point to your own jQuery version. apex.jQuery will still point to the version shipped with APEX.
JavaScript code in an APEX Plug-In:
If you want to use jQuery in an APEX plug-in we recommend to use apex.jQuery. You should even go that far to modify the initialization code of an included jQuery plugin to use the apex.jQuery reference.
What do I mean with that? If you have a look at the JavaScript code of a jQuery plugin you will notice that almost all of them have the following code structure
(function($) {
... plugin code ...
})(jQuery);Looks wired, right? :-) What this actually does is to declare an anonymous JavaScript function with a parameter $ which is immediately called and as parameter value passes in the current jQuery variable. That will allow the function to use $ as jQuery short cut without having to rely on the fact that $ is still used by jQuery.
We recommend to copy the jQuery plugin file and prefix it with apex. (example: apex.jquery.maskedinput-1.2.2.js) to make everybody aware that the file has been modified for APEX. Change the jQuery to apex.jQuery in the initialization code.
(function($) {
... plugin code ...
})(apex.jQuery);Why are we doing all of that?
As a plug-in developer you want to minimize your testing effort and also want to have an environment where you have full control to give proper support. Let's assume you are not doing the above, what happens if a user of your plug-in is using it's own version of jQuery? He might report strange behavior of you plug-in which you are not able to reproduce because you don't know that your plug-in is actually using a different version of jQuery than in your own environment. Using the apex.jQuery namespace reduces your risk and also the risk of your users, you just have to test your plug-ins with the APEX versions you want to support.
Hope that has given some more insides when to use what.
Regards
Patrick
My Blog: http://www.inside-oracle-apex.com
APEX 4.0 Plug-Ins: http://apex.oracle.com/plugins
Twitter: http://www.twitter.com/patrickwolf