Nav

[This is preliminary documentation and subject to change.] 

To display a page in either the base page or a specific target of the interactive show, use the trigger Nav.

The Nav trigger serves one of the two following purposes:

By default, this trigger type causes both the enhancement and its dependencies to display on the consumer's receiver, such as a WebTV® Plus set-top box or a broadcast-enabled computer. If the enhancement and dependencies of the trigger have not yet been broadcast to the viewer's receiver prior to the trigger firing, they are broadcast when the trigger fires and are then displayed in the specified frame.

Syntax

trigger (2 "<URL> [targ:target]") ;

Where

2
is the key denoting that the trigger is Nav.
URL
is a string indicating the location of the HTML page that is to be displayed. This location can be either a fully specified URL, or a URL relative to the spool directory, C:\Program Files\TV Viewer\Enhspool\.
target
is an optional parameter indicating the name of the screen area that the enhancement will appear in. When this parameter is absent, the event will display the specified URL in the highest-level window of the browser.

Remarks

Broadcast Architecture also supports the following alternative formats for Nav triggers:

trigger (3 "target URL") ;

Where all parameters are the same as described preceding, but the key value is three. This format has been kept for compatibility with earlier versions of Broadcast Architecture.

trigger (2 "[target] URL") ;

Where all parameters are the same as described preceding. This is the ASF (Advanced Streaming Format) format used by NetShow.

Examples

In this example, the main HTML page of the interactive show, default.htm, has already been downloaded and is resident in the show's folder, Tales of the Thames\. This trigger is set to fire every 60 seconds until the end of the show.

00:05:32.20 trigger (2 "<Tales of the Thames\default.htm>") repeat 00:01:00.00 until 00:30:00.00 ;

The following statement causes the file "Left_07.htm" and its dependencies to be broadcast by 10:30, and then triggered at 10:30 to appear in the screen area labeled "Left":

trigger (2 "<Left_07.htm> [targ:Left]");

Assuming the HTML file Left_07.htm has only one dependency—one that makes reference to the dependency file banner.gif—the following three statements collectively are equal to the single statement above (provided the necessary bandwidth is available):

00:10:19:00 "banner.gif";
00:10:26:00 "Left_07.htm";
00:10:30:00 trigger (2 "<Left_07.htm> [targ:Left]") only;