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:
- A Declarative Language with Flow Control Support
- XAML Object Elements
- Setting Properties
- Reference Values and Markup Extensions
- Typeconverter-Enabled Attribute Values
- Collection Types and XAML Collection Properties
- XAML Content Properties
- Case and Whitespace in XAML
- More About XAML Syntax
- XAML Root Elements and XML Namespaces
- Events and XAML Code-Behind
- x:Name
- Attached Properties and Attached Events
- Base Classes and XAML
- XAML Security
- Loading XAML from Code
- What's Next
- Related Topics