Validation States on TextBox in Silverlight

So, one of the requirements on the project that I'm working on is that we have a Silverlight TextBox that has to display the error balloon/tooltip. Simple, right? However, this TextBox is actually just displaying data, and the data is entered through a dialog, not directly as text on the screen. Furthermore, to ensure that the user does not attempt to enter the data directly, the TextBox is disabled.

You may know where I'm going with this - my Validation Error tooltip never appears! Why? The default style of a TextBox only shows the tooltip in a focused state! Eventually, I realized this. After looking in the MSDN documentation about TextBox, I was able to get the default style of a TextBox, and I was able to override it's InvalidUnfocused state to do the same as the InvalidFocused state - and it worked!

Now to find a more intuitive way for the user to see that error message without it always being on the screen...

Systematically Update Binding in Silverlight

So, after quite a bit of time in Silverlight, I have learned that DataForms are very powerful entities.  However, they like to hide from me what they are doing.  Therefore, when I get into a situation in which I need to simulate their behavior, this often ends with me banging my head against a wall and typing my query into Google in as many different ways as possible.  Recently, I have been attempting to force a validation on an object that was not in a DataForm... and I had no idea how.  Fortunately, I stumbled upon this forum and it helped me.  So that you don't have to bother reading it (that's why you're at my site, anyway, isn't it?) I have placed the important code snippet here:

BindingExpression bindingExpression = myTextBox.GetBindingExpresion(TextBox.TextProperty);
bindingExpression.UpdateSource();

Poof!  Your TextBox (assuming your TextBox variable is called "myTextBox") will validate.