YUI Library Examples: Menu Family: Handling Menu Click Events

Adding "click" event handlers to items in a Menu

The "onclick" configuration property provides an easy way define a "click" event listener for individual items when building menus from script. The "onclick" configuration property accepts an object literal representing the code to be executed when the MenuItem instance is clicked. The format for the object literal is:


1	{
2	fn: Function (Required), // The handler to call when the event fires.
3	obj: Object (Optional), // An object to pass back to the handler.
4	scope: Object (Optional) // The object to use for the scope of the handler. (By default the scope is the YAHOO.widget.MenuItem instance)
5	}
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The handler that is called when the "click" event fires recieves two arguments: a string representing the name of the event, and an array of arguments sent when the event was fired. The first item in the arguments array is the actual DOM event representing the click. If a value was specified for the "obj" property of the object literal defined for the "onclick" configuration property, it will be passed back as the third argument to the function specified as the "click" event handler.


1	/*
2	"click" event handler for each MenuItem instance - used to log
3	info about the MenuItem that was clicked.
4	*/
5
6	function onMenuItemClick(p_sType, p_aArgs, p_oValue) {
7
8	YAHOO.log(("index: " + this.index +
9	", text: " + this.cfg.getProperty("text") +
10	", value: " + p_oValue), "info", "example9");
11
12	}
13
14
15	/*
16	Instantiate a Menu: The first argument passed to the constructor
17	is the id for the Menu element to be created, the second is an
18	object literal of configuration properties.
19	*/
20
21	var oMenu = new YAHOO.widget.Menu("mymenu", { fixedcenter: true });
22
23
24	/*
25	Add items to the Menu instance by passing an array of object literals
26	(each of which represents a set of YAHOO.widget.MenuItem
27	configuration properties) to the "addItems" method.
28	*/
29
30	oMenu.addItems([
31
32	// Register a "click" event handler for the first item.
33
34	{ text: "Item One", onclick: { fn: onMenuItemClick } },
35
36
37	/*
38	Register a "click" event handler for the second item,
39	passing a string arguemnt ("foo") to the event handler.
40	*/
41	{ text: "Item Two", onclick: { fn: onMenuItemClick, obj: "foo" } },
42
43
44	/*
45	Register a "click" event handler for the third item and
46	passing and array as an argument to the event handler.
47	*/
48	{ text: "Item Three", onclick: { fn: onMenuItemClick, obj: ["foo", "bar"] } }
49
50	]);
51
52
53	/*
54	Since this Menu instance is built completely from script, call the
55	"render" method passing in the DOM element that it should be
56	appended to.
57	*/
58
59	oMenu.render("rendertarget");
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/*
     "click" event handler for each MenuItem instance - used to log 
     info about the MenuItem that was clicked.
*/

function onMenuItemClick(p_sType, p_aArgs, p_oValue) {

YAHOO.log(("index: " + this.index + 
               ", text: " + this.cfg.getProperty("text") + 
               ", value: " + p_oValue), "info", "example9");

}

/*
	Instantiate a Menu:  The first argument passed to the constructor
	is the id for the Menu element to be created, the second is an 
	object literal of configuration properties.
*/

var oMenu = new YAHOO.widget.Menu("mymenu", { fixedcenter: true });

/*
    Add items to the Menu instance by passing an array of object literals 
    (each of which represents a set of YAHOO.widget.MenuItem 
    configuration properties) to the "addItems" method.
*/

oMenu.addItems([

//  Register a "click" event handler for the first item.

{ text: "Item One", onclick: { fn: onMenuItemClick } },

/*
         Register a "click" event handler for the second item, 
         passing a string arguemnt ("foo") to the event handler.
    */
    { text: "Item Two", onclick: { fn: onMenuItemClick, obj: "foo" } },

/*
         Register a "click" event handler for the third item and
         passing and array as an argument to the event handler.
    */
    { text: "Item Three", onclick: { fn: onMenuItemClick, obj: ["foo", "bar"] } }

]);

/*
    Since this Menu instance is built completely from script, call the 
    "render" method passing in the DOM element that it should be 
    appended to.
*/

oMenu.render("rendertarget");

Configuration for This Example

You can load the necessary JavaScript and CSS for this example from Yahoo's servers. Click here to load the YUI Dependency Configurator with all of this example's dependencies preconfigured.

YUI Logger Output:

Logger Console

INFO 1041ms (+0) 12:37:34 AM:

MenuManager

MenuItem yui-gen2 successfully registered.

INFO 1041ms (+0) 12:37:34 AM:

Menu mymenu

Item added. Text: Item Three, Index: 2, Group Index: 0

INFO 1041ms (+0) 12:37:34 AM:

MenuManager

MenuItem yui-gen1 successfully registered.

INFO 1041ms (+0) 12:37:34 AM:

Menu mymenu

Item added. Text: Item Two, Index: 1, Group Index: 0

INFO 1041ms (+0) 12:37:34 AM:

MenuManager

MenuItem yui-gen0 successfully registered.

INFO 1041ms (+1) 12:37:34 AM:

Menu mymenu

Item added. Text: Item One, Index: 0, Group Index: 0

INFO 1040ms (+1) 12:37:34 AM:
MenuManager
Menu mymenu successfully registered.

INFO 1039ms (+0) 12:37:34 AM:
MenuManager
DOM event handlers initialized.

INFO 1039ms (+3) 12:37:34 AM:

Menu mymenu

No source element found. Created element with id: mymenu

INFO 1036ms (+1036) 12:37:34 AM:
LogReader  instance0
LogReader initialized

INFO 0ms (+0) 12:37:33 AM:
global
Logger initialized

YUI Library Examples: Menu Family: Handling Menu Click Events

Adding "click" event handlers to items in a Menu

Configuration for This Example

YUI Logger Output:

Logger Console

Menu Family Examples:

More Menu Family Resources: