See Understanding Techniques for WCAG Success Criteria for important information about the usage of these informative techniques and how they relate to the normative WCAG 2.0 success criteria. The Applicability section explains the scope of the technique, and the presence of techniques for a specific technology does not imply that the technology can be used in all situations to create content that meets WCAG 2.0.
Microsoft Silverlight, versions 3 and greater
Silverlight managed programming model and Silverlight XAML
This technique relates to:
See User Agent Support Notes for SL24. Also see Silverlight Technology Notes.
The objective of this technique is to use the AutoPlay property
of MediaElement object, which prevents the MediaElement from
playing its media source automatically.
By default the value of AutoPlay is true, which causes
any media that is the Source of the MediaElement to
play as soon as either the entire source file is loaded (for nonstreaming
media) or an initial buffer is loaded (for streaming media). To prevent
the possible accessibility issues, developers can instead specifically set AutoPlay to
false, so that the user always controls whether the media plays. This
technique would thus be used in combination with providing user interface
controls that go along with the MediaElement, and
that enable the user to control the media. In particular, the user
interface controls enable the media to play, pause or stop, with event
wiring for those controls associated with the Play, Pause or Stop methods
of the MediaElement object.
This example has a UI definition in XAML and interaction logic in C#.
The following is the basic UI in XAML. Note the AutoPlay="false" setting.
<UserControl x:Class="MediaElementControlsAutoPlay.MainPage"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
>
<Grid x:Name="LayoutRoot">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*" />
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<MediaElement x:Name="media" Source="/xbox.wmv"
Width="300" Height="300"
Grid.Column="0" Grid.Row="0" Grid.ColumnSpan="3"
AutoPlay="False"
AutomationProperties.Name="Video of new Fable game for XBox"
/>
<Button Click="StopMedia"
Grid.Column="0" Grid.Row="1" Content="Stop" />
<Button Click="PauseMedia"
Grid.Column="1" Grid.Row="1" Content="Pause" />
<Button Click="PlayMedia"
Grid.Column="2" Grid.Row="1" Content="Play" />
</Grid>
</UserControl>
The following is the C# logic.
private void StopMedia(object sender, RoutedEventArgs e)
{
media.Stop();
}
private void PauseMedia(object sender, RoutedEventArgs e)
{
media.Pause();
}
private void PlayMedia(object sender, RoutedEventArgs e)
{
media.Play();
}
This example is shown in operation in the working example of Media Element Controls with AutoPlay False.
Resources are for information purposes only, no endorsement implied.
Silverlight
Media Framework - a framework and a media player control implementation
that incorporates many of the Silverlight techniques related to MediaElement
Using a browser that supports Silverlight, open an HTML page that
references a Silverlight application through an object tag. The application
is expected to use a MediaElement object to play
prerecorded media.
Check that the media does not play automatically as soon as the application loads and displays. Rather, the user is presented with a user interface that can start the media per the user's action.
#2 is true.
If this is a sufficient technique for a success criterion, failing this test procedure does not necessarily mean that the success criterion has not been satisfied in some other way, only that this technique has not been successfully implemented and can not be used to claim conformance.