SharePoint

SharePoint Custom Web Parts from Cheers (The TV Show)

Scott Spradlin — Fri, 11 Jul 2008 00:49:45 GMT

So there I was -- another day of writing slick AJAXified custom SharePoint web parts. This was a simple one. A series of dropdowns that cause subsequent dropdowns to be re-populated with increasingly restrictive data.

Planet
Continent
Country
etc.

But, when I changed the planet choice to be "Earth" the continent choice DID populate with the continents on earth but it caused a complete page round trip -- not the smooth AJAXified action I expected. Plus, my UpdateProgress panel wasn't being displayed at all, even though I put a 10 second pause in my event handler. What's wrong? I'm comparing my CreateChildControls against previous similar projects that worked in the past and everything appears to be correct.

Can't figure it out so I start randomly moving things around to see what effect that has. (Highly technical debugging technique.) I move a button up into the UpdatePanel and THAT WORKS! It's the dropdown! AJAX hates my dropdowns!

I start looking into why it's so. Do I need to specify the <TRIGGER> manually for these controls? Say it ain't so! I've never had to do that in the past. Wait, someone's post says "make sure you give your dynamically created controls an ID or AJAX won't work for them!" I add a line similar to:

      MyDropdownControl.ID = "_AnIdHere_"

...and by golly now it works. Moral of the story? Always give your dynamically created controls a proper ID. Just like Norm, web parts want to go -- wait for it -- where everybody knows their name.

Technorati Tags: SharePoint,Web Parts,AJAX

Duplicate GUID Encountered?

Scott Spradlin — Wed, 09 Jul 2008 20:51:10 GMT

My friend Todd Kitta and I were having a discussion on GUIDs. He said that one day he compared the number of possible GUIDs to the number of grains of sand estimated to be on all the beaches on the earth.

Number of GUIDs	340,282,366,920,938,463,463,374,607,431,770,000,000 *
Grains of sand	75,000,000,000,000,000,000 *

I guess that's why we don't typically put in error checking to detect duplicate GUIDs. It hasn't yet, but if it can happen, it'll happen to me.

Technorati Tags: Programming

* Numbers estimated based on the decimal precision of our scientific calculator as provided in Vista.

Publishing InfoPath To SharePoint: "the following url is not valid" Error

Scott Spradlin — Sun, 08 Jun 2008 20:27:50 GMT

File this one under the "yet another useless error" category. I was trying to publish a form that I prevously had succesfully published to my development VPC. Every time I tried to publish it would say "the following url is not valid" when I entered the path to the sharepoint site.

Doing the standard search for the error yielded several potential solutions ranging from re-installing .NET, make sure there's a site at the root "/" and make sure there's a SSP.

Additional searching yielded the other option of stopping the "System Event Notification" Check out this blog entry.

Don't you just love obscure error messages?

Technorati Tags: SharePoint,Programming

Debugging Half-Installed-AJAX on SharePoint

Scott Spradlin — Tue, 22 Apr 2008 16:06:16 GMT

You've been there. "It works on my box!" Our new SharePoint web parts don't work in production!

This project called for a suite of data entry grids inside custom SharePoint web parts. The customer already owned Infragistics' NetAdvantage for ASP.NET so I used their UltraWebGrid. Very slick and easy to deploy with your custom web parts.

The primary feature they wanted was the cool Excel-like cut-n-paste functionality but that wasn't working in our production environment. At the beginning of the project, the client said "Oh, we already have AJAX things running in that environment...it's installed and ready to go." Silly me, I didn't follow through and verify it. My solution installed without the infamous "The Web Part you attempted to add no longer exists in the Closed Web Parts Gallery" helpful error message...which means that all the dlls that I'm referencing apparently are there.

After the page loads -- apparently successfully -- and we mouse over the grid, we see the tiny little error message down in the corner of the browser. Digging deeper I see that JavaScript has encountered a problem and is helping me out by saying "Object Expected". Even gives me the line where this object is expected. It's the line that is 65 million characters long that contains all the html for the grid. So, IE knows the object it's expecting, why can't it share that tidbit?

Well, we know it's event oriented because the error happens when the mouseover should be firing. Maybe the JavaScript code that's supposed to fire isn't being loaded properly I say to myself. (Infragistics cleverly bundles all the JavaScript support files as embedded resources so there's no additional headache of distributing them, setting permissions, etc.) So it looks like it's loading them but apparently it's not.

Specifically, one of the changes you're instructed to make to the web.config for AJAX installation supports the callbacks for embedded scripts through ScriptResource.axd.

<add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/>

Someone had not updated the web.config on the production web front end to include all the changes needed for complete AJAX support. Thanks buddy. :)

I made the seven little changes and bingo -- success.

Technorati Tags: SharePoint,AJAX,Programming