I got another question about an issue in Silverlight 2.0 Beta 2. My collegue who is at the moment working on a video-player came to me and asked me why MouseLeftButtonDown- and Up didn't work on the slider and after 2 minutes of Googling we found out that he wasn't the only one faced with this problem. I started by Googling a bit more. Google is a developers best friend, but I couldn't find a solution. I found the reason for the problem, which I confirmed by checking the sliders code in Reflector. It is actually not a change in Silverlight as such, but in the controls that ship with Silverlight. For some reason Microsoft changed the implementation of their controls from Beta 1 to 2 and started letting each individual template part handle their on mouse events.So each part of the control encapsulates itsfunctionality nicely and sets the Handled-property of the EventArgs to true in their eventhandlers. This causes the event to stop bubbling and also renders the MouseLeftButtonDown, Up and so on the control more or less useless.
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