Navigation Control with WebObjects

With a reusable component, you could define the same page like this:

<HTML>
<HEAD>
    <TITLE>World Wide Web Wisdom, Inc.</TITLE>
</HEAD>
<BODY>
Please come visit us again!
<!-- start of navigation control -->
<WEBOBJECT NAME="NAVCONTROL"></WEBOBJECT>
<!-- end of navigation control -->
</BODY>
</HTML>

The thirteen lines are reduced to one, which positions the WebObject named NAVCONTROL. The declarations file for this page binds the WebObject named NAVCONTROL to the component named NavigationControl:

NAVCONTROL: NavigationControl {};

All of the application's pages would have entries identical to these in their template and declarations files.

WebObjects Builder makes reusable components even more attractive by providing a graphical way to create and maintain them. With the builder, you can assemble these components graphically and then put them on a palette for later use. Adding a custom reusable component to you application becomes a simple matter of dragging it from Builder's palette into your application and binding its attributes to variables or methods just as you would a dynamic element you drag from Builder's palettes. See "Advanced WebObjects Builder Tasks" in the WebObjects Builder Guide for more information.

NavigationControl is a component that's defined once, for the use of all of the application's pages. Its definition is found in the directory NavigationControl.wo in the file NavigationControl.html and contains the HTML for the table:

<CENTER>
<TABLE BORDER = 7 CELLPADDING = 0 CELLSPACING = 5>
    <TR ALIGN = center>
    <TH COLSPAN = 4> World Wide Web Wisdom, Inc.</TH>
    </TR>
    <TR ALIGN = center>

    <TD><A HREF = "http://www.wwww.com/home.html"> Home <a></TD>
    <TD><A HREF = "http://www.wwww.com/sales.html"> Sales <a></TD>
    <TD><A HREF = "http://www.wwww.com/service.html"> Service <a></TD>
    <TD><A HREF = "http://www.wwww.com/search.html"> Search <a></TD>
    </TR>
</TABLE>
</CENTER>

Since NavigationControl defines a group of static elements, no declaration or script file is needed. However, a reusable component could just as well be associated with complex, dynamically determined behavior, as defined in an associated script file.

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