Recently I spent a number of hours banging my head against a
wall trying to customize some of the rich DHTML functionality in
SharePoint. Basically I wanted to remove the Workflows option from
the default list item context menu (Edit Control Block).
I couldn't use a feature as this doesn't work for the built in
elements and I didn't want to mess with CORE.js as it's never good
practive and would effect all doc libs. So I worked out which
method to override and then added this code inside PlaceHolderMain
for the allitems.aspx page like so:
<script type="text/javascript">
function AddWorkflowsMenuItem(m, ctx)
{
//do nothing
}
</script>
The idea is that it will override the defualt behaviour of
adding the menu with nothing - and hence not show the menu. For
some reason this didn't work, in fact when debugged, the JavaScript
was throwing an error. Interestingly it worked in FireFox so I knew
I wasn't doing anything wrong. Initially I thought maybe this could
be a browser compat thing but overriding a method is the same in
any browser.
Eventually it dawned on me that the problem was the core.js
script had not yet been loaded. The culprit was the ScriptLink
control:
<SharePoint:ScriptLink language="javascript" name="core.js"
Defer="true" runat="server"/>
Basically this control is referencing the CORE.js external
javascript file. However becuase the defer tag is specified it is
loaded after my function override is declared. This deferred
loading is usually a good thing as the page doesn't have to halt
it's loading for the script - instead it is loading in the
background. This gives a perceived performance boost to the
user.
In my case I was able to add the scriptlink without the defer
tag to just the page I needed to (allitems.aspx). All other pages
in the site can still benefit from the deferred loading and I get
the desired functionality:
