Grails的： <script> vs. <g:javascript>

Question

Can anyone please explain the difference between these two tags and how Grails sees one vs. the other? I have a table with click and hover effects which don't seem to happen when I import jquery using:

<g:javascript library="jquery" />

but do when I do this:

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

and I want to use the previous tag because other Grails tags such and remote forms rely on it for their built in ajax capabilities.

Answer 1

The first is the custom Grails tag and tries to load the Javascript library by that name. If you're using the Resources plugin, then the call delegates to that for loading of the library. Take a look at JavascriptTagLib.groovy to see what the custom tag does.

The latter is just the regular HTML script element, and attempts to fetch a script at the location provided.

The issue you're running into may slightly depend on the version of Grails you are running too. Looks like 'jQuery' is not a valid library in Grails 1.3.x:

library (optional) - The name of the library to include. Either "prototype", "scriptaculous", "yahoo" or "dojo"

You may want to make sure that your path is correct and you either have the Grails jQuery plugin installed, or you have the library in your web-app/js directory. Grails 2.x comes with jQuery by default, but older versions did not.