Expression Blend Software Development Kit allows you to extend the capabilities of behaviors in Expression Blend. Expression Blend 3 SDK also contains following redistributable components: SketchFlow Player; Custom VSM for Fluid Layout; Font Embedding enhancements. Expression Blend 3 SDK is required to view an Expression Blend 3 project that uses any of these components if Expression Blend 3 isn’t installed. “Expression Blend 3 introduces behaviors, which’re reusable pieces of packaged code that can be dragged onto any object, and then fine-tuned by changing their properties. Behaviors allow you to add interactivity to your apps without having to write any code. Behavior API consists of three core classes: Trigger, Action and Behavior.” This SDK explores how to write each of these components, and contains a few code samples to help you get started. Programming reference topics’re provided for both Windows Presentation Foundation (WPF) and Silverlight.
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