Silverlight standard loading animation does not get displayed

Can anybody enlighten me as to how the standard Silverlight loading animations (the swirling blue balls) are embedded in a Silverlight application and how they work? I currently don't see it although loading the xap takes long enough for the loading animation to be displayed.

The problem is that I'm creating a xap dynamically and trying to write it to the 开发者_如何学编程Response Stream which might somehow interfere with the way most Silverlight applications work. So maybe there's something missing from the original aspx page or ClientBin that should be there that has been lost by accident.

I haven't found any helpful information about how the loading animation is integrated into Silverlight that could help me debug the problem so far. Does anyone know what the animation needs to triggered as expected?

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It's the Silverlight plugin that displays that animation - not each SL application itself. Can you post your code? Perhaps you're not specifying the content length so the plugin has no idea how big the download will be.