Datasheet

Figure 1-3

These categories are tightly coupled and a user interaction often triggers an exchange with a server

that leads to a modification in the document. To illustrate the point, you are invited to follow some

of the actions that are performed after the document is loaded. One of the functions called in

init is

initMenuBar(). Most of the instructions in this function are copied from examples coming with the

YUI. (Unlike most of the other modules that are nicely wrapped in classes that you just have to instanti-

ate, the menu bar module requires quite a few instances of copying and pasting JavaScript instructions.)

Among these instructions, the ones that operate the magic and bring the menu bar to life in the file

menubar.js are:

var oMenuBar = new YAHOO.widget.MenuBar(

“menubar”,

{ fixedcenter: false }

);

oMenuBar.render();

YAHOO.buzzWatch.menuBar = oMenuBar;

YAHOO.buzzWatch.menuGo = oMenuBar.getItem(1);

The first instruction creates a menu bar object. The second one, oMenuBar.render(), applies the

modifications needed to instantiate the menu bar in the HTML document. The first argument of the

YAHOO.widget.MenuBar constructor call, “menubar”, is the identifier of an element of the HTML

Chapter 1

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