The excl element is a time-container element in which only one media element can be played at a time, but the playback order of the child elements is not determined. Use an excl element if you want to control when child elements begin based on variable criteria. For example, a child element can be triggered by using either a programmatic event or a begin attribute that explicitly specifies a start time. Unlike child elements of a seq element, which play in order once the seq element has been activated, the child elements of an excl element do not play unless they are explicitly started.
In the following example, the values for the begin
attributes determine the playback order of the media
elements. Since its begin value is 0 seconds
0s), the media element media2 plays
immediately. The third element, media3, is set to begin when media2
media2.end). Likewise, the fourth element,
media4, is set to start at the end of media3, and the first
element, media1, is set to start when media4 ends.
<?wsx version="1.0"?> <smil> <excl> <media id="media1" src="Video1.wmv" begin="media4.end"/> <media id="media2" src="Video2.wmv" begin="0s"/> <media id="media3" src="Video3.wmv" begin="media2.end"/> <media id="media4" src="Video4.wmv" begin="media3.end"/> </excl> </smil>
An excl element is often used in conjunction with priorityClass elements, which control how one media element interrupts the playback of another element. For more information, see priorityClass element.
Attributes modify the properties of a playlist element. You can use the following optional attributes with an excl element.
|begin||Specifies the amount of time until the excl element becomes active and its child elements start playing. For more information, see begin attribute.|
|dur||Specifies the length of time that the excl element is active and its child elements play. For more information, see dur attribute.|
|end||Specifies when the excl element becomes inactive and its child elements stop playing. For more information, see end attribute.|
|endSync||Specifies which child element determines when the excl element ends. For more information, see endSync attribute.|
|syncEvent||Specifies a string used to trigger the beginning or end of an element in a wrapper playlist. For more information, see syncEvent attribute.|
|id||Specifies a name for the excl element that can be referenced by other elements. For more information, see id attribute.|
|repeatCount||Specifies the number of times the child elements within the excl element repeat before stopping. If no value is specified, the element is played once. For more information, see repeatCount attribute.|
|repeatDur||Specifies the length of time the child elements within the excl element repeat before stopping. For more information, see repeatDur attribute.|
Last, by default.