I simply do not understand votes of 1 for an article like this - it may not be perfect but it is a very nice article with difficult to find information that required considerable effort to put together as a free gift for others.
Continue voting 1 for worthwhile articles and you will stop people from taking all of the effort to develop and submit worth while articles. If you feel the article needs significant improvement, then write and submit one and maybe you too will see what it feels like to receive some 1's.
I don't know, but this XAML approach seems to push 'develpers' into the wrong direction. In most of the examples I have seen so far (including this one) a lot of code duplication can be found. This example is not reusable, and not object oriented at all. Such examples should not be shown at all. I don't know how people can give this one a vote of 5!
Despite the poor implementation (non object oriented with a lot of code duplication) the worst thing to mention is the vertical separators between the 'buttons'. These separators are part of the background image - believe it or not!
i tried to implement the navbar in basic .net and have a problem at point point 10. After I replaced the grid with the rectangle with the navbar and test the ControlDemoTestPage the browser loads silverlight to 100% and then it loads and loads and nothing happens. Also when i look at page.xaml in blend, i could not see the navbar. I have deleted the events, this is not the problem. I also hooked up the events, but the problem is not solved. I downloaded the code and copied your version of generic.xaml and the problem still exists. Do you have an idea what i'm doing wrong?