XAML Integrator

Integration of Visual Studio and Expression Blend through XAML

Monday, October 13, 2008

About XAML

XAML LogoXAML or Extensible Application Markup Language (pronounced zammel [ˈzæmɫ̩]) is a declarative XML-based language created by Microsoft which is used to initialize structured values and objects.

XAML is used extensively in .NET Framework 3.0 technologies, particularly Windows Presentation Foundation (WPF) and Windows Workflow Foundation (WF).
In WPF, XAML is used as a user interface markup language to define UI elements, data binding, eventing, and other features. In WF, workflows can be defined using XAML.

XAML elements map directly to Common Language Runtime object instances, while XAML attributes map to Common Language Runtime properties and events on those objects.

Anything that is created or implemented in XAML can be expressed using a more traditional .NET language, such as C# or Visual Basic.NET. However, a key aspect of the technology is the reduced complexity needed for tools to process XAML, because it is based on XML. As a result, a variety of products are emerging, particularly in the WPF space, which create XAML-based applications. As XAML is simply based on XML, developers and designers are able to share and edit content freely amongst themselves without requiring compilation.
As it is strongly linked to the .NET Framework 3.0 technologies, the only fully compliant implementation as of today is Microsoft's.

XAML files can be created and edited with visual design tools such as Microsoft Expression Blend, Microsoft Visual Studio, and the hostable Windows Workflow Foundation visual designer.
They can also be created and edited with a standard text editor, a code editor such as XAMLPad, or a graphical editor such as Vector Architect.

A XAML file can be compiled into a .baml (Binary XAML) file, which may be inserted as a resource into a .NET Framework assembly. At run-time, the framework engine extracts the .baml file from assembly resources, parses it, and creates a corresponding WPF visual tree or workflow.

When used in Windows Presentation Foundation, XAML is used to describe visual user interfaces. WPF allows for the definition of both 2D and 3D objects, rotations, animations, and a variety of other effects and features, but when used in Windows Workflow Foundation contexts, XAML is used to describe potentially long-running declarative logic, such as those created by process modeling tools and rules systems.

XAML uses a specific way to define Look and Feel called Templates, different from the Cascading Style Sheets syntax, but closer to XBL.

Although the European Committee for Interoperable Systems argues that Microsoft's use of XAML in its Silverlight product aims to introduce content on the web that can only be served from the Windows platform, XAML is viewable in non-Microsoft browsers on Windows and Mac, and Microsoft provides direct support for the development of a Silverlight viewer for GNU/Linux called Moonlight.

More Info:

The Integrator

XAML represents a bridge between the designer and developer teams.
A new role has emerged as the result of this fusion, that Paul Alexander, a technical program manager with IdentityMine, calls the integrator:
"The Integrator understands the needs of the developer while also supporting the needs of the designer to assure that the app's UI is as compelling as it was designed, while also validating that the concepts can be realized in code from the developer."

The integrator deals mostly with XAML code and provides an interface between the developer and designer, by structuring and modularizing the XAML.

Therefore, the ideal integrator must posess strong design skills and a thorough understanding of XAML and Windows Presentation Foundation (WPF) concepts such as inheritance, styles, and resource lookup.

The Designer<->Integrator<->Developer Model allows the design team to leave the XAML unattended and focus on having their assets effectively integrated into the project.
Designers can work with tools such as Expression Design, Inkscape or Adobe Illustrator and output the results as XAML.
The integrator then integrates the XAML into the project and passes it on to the developers, who need not to be concerned with design issues.
Obviously, this model also works perfectly well the other way around, and in some cases it is advisable to have the developer team establish the foundations of the project.

A recently released tool by Microsoft, Expression Blend, makes this transition even easier, by accepting and generating XAML code that can be directly imported/exported from/to Visual Studio.