Channel Browser

A user launches Channel Browser to select and to view a mobile channel. The browser follows the special Mobile Channels transport protocol to render the content. To conserve storage space and bandwidth, channel content is expressed both in terms of a template, which is a script file, and data to be filled into that template. When data arrives and must be displayed, Channel Browser runs the appropriate script to process the data and display it in HTML format.

Channel Browser's main window holds a command bar, a channel bar, and an HTML control. The command bar features a menu and a toolbar. The channel bar displays icons of subscribed channels. The icon files can be of the GIF or JPEG format. You specify the icons in CDF files using the LOGO tag with STYLE setting to "ICON."

<LOGO STYLE="Icon" 
         ID="icon1"  
       HREF="http://www.msnbc.com/mobileChannels/icon1.gif"/>

The HTML control displays the content for the current channel. You are responsible for supplying the content, specifying page layout, and providing the navigation scheme from within the channel. Except for a smaller screen size, Channel Browser is modeled after the IE4 browser on a desktop computer. This similarity provides a consistent Web experience for Windows CE users.

Channel Browser includes Home Channel, a virtual channel at the top of the channel hierarchy, which you can see in Channel Explorer. Home Channel contains links to the main pages of all subscribed channels. A built-in home channel script displays the subscribed channels. Users can access this channel using the Home Channel command from either the Go menu or the appropriate button on the toolbar.

From the Go menu of Channel Browser, a user can choose "Explore Channel…" to bring up the Channel Explorer dialog box. This pop-up window provides a hierarchical view of the mobile channels. It offers users a shortcut to channel navigation without having to trace through all the intermediate pages. Each channel and item may have an icon associated with it. Top-level channels are listed in order, as specified in Preferences. Within a channel, the subchannels and items are listed according to the hierarchy specified in the CDF file. The icon displayed at each level is derived from the LOGO tag in CDF, as explained earlier. If you fail to supply a logo, the default channel or item icon is used. The <TITLE> flag specifies the name of each channel. For example,

<CHANNEL>
   <TITLE>Mobile Channel Tips</TITLE>
    …
</CHANNEL>

By choosing the Properties command on the File menu of Channel Browser, a user can examine item properties from the Item Properties panel for any item page displayed in the browser. The information, including the title of the item and the date of creation and last modification, is extracted from the CDF file defining the item.