Code:

{!RequireScript("/soap/ajax/9.0/connection.js")}
// We're going to just do blanket error coverage.
try
{ 
// Create an SObject for the opportunity we are on.
Opportunity = new sforce.SObject("Opportunity")
// Populate the ID field for the update call.
Opportunity["id"] = "{!Opportunity.Id}"
// Query the Total Amount 2 field from the line items.
Products = sforce.connection.query("select Total_Amount_2__c from OpportunityLineItem where OpportunityId = '{!Opportunity.Id}'")
// Create a QueryResultIterator to total the Total Amount 2 field.
ProductIterator = new sforce.QueryResultIterator(Products)
// Zero the Amount 2 field in our record update object.
Opportunity["Amount_2__c"] = 0
// While there are more line items to add together...
while(ProductIterator.hasNext())
{ // ... get the next line item ...
  Product = ProductIterator.next()
  // ... and add it to the opportunity's Amount 2 field.
  Opportunity["Amount_2__c"] += Product.getFloat("Total_Amount_2__c")
}
// Update the opportunity's Amount 2 field.
sforce.connection.update([Opportunity])
// Refresh the page.
} catch(e)
{ // Show the soap error, javascript error, or the error object if none of the above.
  alert("There was an error processing your request: "+e.faultCode?e.faultCode:e.message?e.message:e)
}
// Refresh the page's contents.
window.top.location.href = window.top.location.href

Note, I designed this to be a button/link, not an S-Control. To use it, go to Setup | App Setup | Customize | Opportunities | Buttons and Links. Choose the "Execute JavaScript" behavior when using this code. This will not be an automatic update; the user will need to click the button or link to cause the code to execute. You could make it an automatic page script, but those are annoying as they slow down the browser and are easy to accidently create infinite loops. This way, the user expects a delay while the browser calculates the new total and updates the opportunity (this normally takes 1-2 seconds, depending on the number of line items).

~ sfdcfox ~

Message Edited by sfdcfox on 08-06-2007 03:24 PM

Message Edited by sfdcfox on 08-06-2007 05:03 PM