The architecture of WPF spans both managed code and native code components. However, the public API exposed is only available via managed code. While the majority of WPF is in managed code, the composition engine which renders the WPF applications is a native component. It is named Media Integration Layer (MIL) and resides in milcore.dll. It interfaces directly with DirectX and provides basic support for 2D and 3D surfaces, timer-controlled manipulation of contents of a surface with a view to exposing animation constructs at a higher level, and compositing the individual elements of a WPF application into a final 3D "scene" that represents the UI of the application and renders it to the screen.[21][22] The Desktop Window Manager also uses the MIL for desktop and window composition.[23] The media codecs are also implemented in unmanaged code, and are shipped as windowscodecs.dll.[21] In the managed world, PresentationCore (presentationcore.dll) provides a managed wrapper for MIL and implements the core services for WPF,[21] including a property system that is aware of the dependencies between the setters and consumers of the property, a message dispatching system by means of a Dispatcher object to implement a specialized event system and services which can implement a layout system such as measurement for UI elements.[22] PresentationFramework (presentationframework.dll) implements the end-user presentational features, including layouts, time-dependent, story-board based animations, and data binding.[22]
An object tree representation forms the basis of the Silverlight run-time programming model, and enables programmatic access to every programming entity or element part of a running Silverlight application. The object tree representation is particularly useful for accessibility frameworks, and in turn for assistive technologies that use the accessibility framework as a client. The relationships and item order in the object tree also define the default reading order, as well as the default tab sequence for default Silverlight key handling. The Silverlight plug-in code that renders Silverlight content into the plug-in display area is literally reading the same run-time object tree that is being simultaneously reported to the accessibility frameworks or other subsystems of Silverlight (for example, printing APIs).
Presentation Framework Dll Silverlight Download
Relying on default automation peer behavior is the preferred Silverlight technique for supplying the accessibility framework "Name" information, so long as the default peer promotion actually does produce a usable name. Using default behavior is preferred because re-using the strings that are already used in the general visual presentation is less likely to result in accessibility-specific strings being forgotten by the application author, or get decoupled from visible UI in a revision process.
In this example, several properties that influence the items presentation behavior of the Silverlight core control ListBox are adjusted to make it suitable for a navigation control. The behavior of this control is that when the tab sequence reaches the control, "next" or spatial navigation continues on to other controls, rather than through the child controls of the list's items/options. This is enabled and properly reported because ListBox reports its accessibility framework role as "List", uses TabNavigation = Once as default (because it is the default, TabNavigation does not have to be set explicitly in the markup). ListBox has default key handling for the arrow keys (to enable traversing the choices in the menu by keyboard-only). The control could also be visually a menu or perhaps other user interface control metaphors, depending on how it is visually templated and composited. Regardless of appearance, the accessibility framework and any assistive technologies based on that framework will treat the control as a "List". This example is templated as a horizontally oriented toolbar-type control. The items in this example are Button controls, but could be templated to not appear quite as button-like, or could instead use another focusable control for the items such as a read-only TextBox.
The objective of this technique is to change the presentation / visual appearance of text, by setting several of the font-specific properties in the Silverlight API. Changing such properties does not change the semantic meaning of the text, nor does it alter the representation of the text that is available to assistive technologies through the Silverlight support of the UIA accessibility framework. By using font properties, it is possible to introduce a wide variety of presentation changes to fonts that do not introduce semantic elements that interfere with an assistive technology's view of text in the Silverlight application. In particular, adjusting font properties will make it possible to avoid any need for use of images of text, yet still provide a wide range of choices for text presentation.
Close the browser. Repeat the test with an accessibility framework test tool running. There should be no difference in the structure or relationships in the accessibility view beyond the presentation changes.
The CLR is a great platform for creating programming languages, and the DLRmakes it all the better for dynamic languages. Also, the .NET framework(base class library, presentation foundation, Silverlight, etc.) givesdevelopers an amazing amount of functionality and power. 2ff7e9595c
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