I have a new addition to my samples gallery. This sample was inspired by a question I answered on the silverlight.net community forums. The idea of creating a “scratchable” surface intrigued me, so I decided to make a full-blown sample utilizing WritabeBitmap.

It took me about 8 hours from start to finish to implement the sample. Most of it I spent fussing over the application’s look-and-feel and getting the brushes to work properly. Some of my failed experiments with brushes produced very interesting, almost impressionistic-looking, results.

The ideas I considered for development, but not included in the sample: changing brush shape depending on stroke’s velocity; rotating brush based on the angle of the stroke; and multi-touch support.

• View "Scratch"
• Download sample source

If you’re building a Silverlight application for Facebook, you have two choices: (1) build a stand alone application and use Facebook Connect for authentication, or (2) create a canvas application that will appear on a Facebook site and use the parameters passed to iframe to establish a session. The former is well covered in the Facebook Toolkit documentation, but I couldn’t find any examples of how to embed a Silverlight application within a Facebook iframe. It took a few days worth of research and experiments to get it right and I hope this post will be helpful to anyone who is working on Silverlight canvas application for Facebook.

Embedding Silverlight into Facebook canvas

I know three ways of embedding Silverlight application into a Facebook canvas.

(1) Select the IFrame option for Render Method in Canvas section of the application settings and embed the Silverlight application inside the iframed page using standard methods (object tag, silverlight.js, etc.).  (2) Use <fb:iframe> tag in fbml based canvas. (3) Use fbml tag <fb:silverlight>. The <fb:silverlight> tag would be the preferred method, but according to the Facebook wiki, the tag is not implemented at this time. That leaves only options 1 and 2 available – embed Silverlight in iframe.  Whether you go with IFrame canvas or use <fb:iframe> tag in fbml, the following steps are the same:

More...

I spent some time recently going through some of my older projects and consolidating different button styles I’ve designed over time into a single project.

You can see the results in this Silverlight sample application.