I'm new to salesforce.com and VisualForce/Apex.  I have developed a custom Page that renders a PDF, but I need to conditionally display content based on a field value set on a product - if that product is a line item on the quote.

Specifically when I load this page from the quote and display quote information and line item detail (already done), I need to display a div if any of those products' "Agreement_Supplement__c" picklist field contains the value "Supplement A" - but I have another div that needs displayed if that same picklist field contains the value "Supplement B".  It seems that I need to create a function that takes in the orderid and supplement name and returns a true/false.

Esentially in my page I would like to be able to do something similar to if(hassupplement(theorderid, thesupplementname),"display:block;","display:none;").  I've read through the documentation and tried a few things, but haven't been able to acomplish this yet.