This is a repost of an article i upped on my blog back in Feb 2007

Purpose:

Apply a Sharepoint Theme to any provisioned webs based off any Site Definition via Feature Stapling.

Background:

A pre-deployment task for our implementation of WSS 3.0 is to brand Sharepoint. There are several ways to customize a Sharepoint implementation. One of the simpler methods is to create your own Sharepoint Theme.

Themes, once applied to a Sharepoint web, allow you to skin the look and feel of a significant portion of the pages that users come into contact with whilst using a site. We required fairly minimal customizations which were mostly serviced through custom stylesheets.

In our implementation of WSS 2.0 we used a custom site definition (based off the STS site def) to service our branding needs, along with modifications to bunch of admin pages on the front-end servers.

We could of taken the same approach of creating a new custom site definition which would give us more flexibility in terms of customization, but this approach isn't favourable due to the fact that we wanted all of the OOTB site definitions available for use, not just the standard team site definition.

Yes, we could create a custom site def based off each of the default site defs (STS, MPS, WIKI, BLOG etc), but this approach is no longer necessary for simple customizations due to a new feature in Sharepoint called umm.. Features. A Feature as defined in the SDK manual:

"Features reduce the complexity involved in making simple site customizations, and are robust when upgrades are applied to a deployment. Features eliminate the need to copy large chunks of code to change simple functionality. Features thus reduce versioning and inconsistency issues that may arise among front-end Web servers. Features make it easier to activate or deactivate functionality in the course of a deployment, and administrators can easily transform the template or definition of a site by simply toggling a particular Feature on or off in the user interface"

Another alternative would be to directly modify the OOTB site definitions. This however is not supported. So what we wanted in a nutshell is a way to skin any type of Sharepoint site with as few modifications to Sharepoint files as possible.

The solution also had to have three main features: 

Req 1. Our custom Theme needs to be applied to sites automatically. (The standard process to apply a Theme is a manual one, 'Site Actions->Site Settings->Look and Feel->Site Theme')

Req 2. Any changes made to the custom Theme post deployment, must be reflected in existing sites that were provisioned after this solution was deployed.

Req 3. Modify as few Sharepoint files as possible

Solution:

A quick rundown of the solution is as follows:

1. Create a custom Theme. CSS importing is used to get around Sharepoint caching a copy of the Theme's css file, which would violate Req 2.
2. Create a Sharepoint Feature that applies a Theme to a site when a site is provisioned.
3. Create another Feature that staples the previous Feature to all site definitions. This idea came from Chris Johnson's blog.
4. Deploy the second feature at the Farm scope, which attaches the first feature to all sites within the Sharepoint farm. For ease of deployment i have used the WSS Solution framework.

Detailed Description:

1. Creating a Theme is detailed here WSS 3.0 SDK - How to: Customize Themes  or alternatively read Shane Perran's blog. In order to utilize the css 'indirection' method see Bil Simser's "Automagically updating themes" blog entry

2.

Feature.xml

ApplyTheme.cs

3.

Feature.xml

Elements.xml

4.

I have attached the VS 2005 solution. All you need to do is replace the GUIDS and Public Keys, sign the assembly and fix up any broken references. Oh and change names of classes, dll, etc so they mean something to you.

See the Sharepoint Solutions Team blog for an example VS 2005 solution, explaining all the files in the project and also check out Andrew Connell's HowTo on creating Solution files.

To deploy the Solution, here is a script that was posted by Daniel Larson on the SDK page Deploying a Solution.

@set PATH=C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\BIN;%PATH%
stsadm -o deactivatefeature -name MyCustomTheme -url  http://localhost
stsadm -o retractsolution -name MyCustomTheme.wsp -immediate -allcontenturls
stsadm -o execadmsvcjobs
stsadm -o deletesolution -name MyCustomTheme.wsp -override
stsadm -o execadmsvcjobs
stsadm -o addsolution -filename C:\MyCustomTheme.wsp
stsadm -o execadmsvcjobs
stsadm -o deploysolution -name MyCustomTheme.wsp -immediate -allcontenturls -allowGacDeployment -allowCasPolicies
stsadm -o execadmsvcjobs  

Limitations:

The solution does not automatically apply the Theme to any sites that have already been provisioned.

Any feedback is appreciated,

Tom.