YUI Library Examples: Menu Family: Listening For Menu Events

Menu Family: Listening For Menu Events

This example demonstrates how to listen for DOM-related events. Interaction with the Menu will result in event information being output to the console. Please note: Disabled MenuItem instances do not fire DOM events. This is demonstrated with the MenuItem named "MenuItem 2."

Note: By default clicking outside of a Menu instance will hide it. Additionally, MenuItem instances without a submenu or a URL to navigate to will hide their parent Menu instance when clicked. Click the "Show Menu" button below to make the Menu instance visible if it is hidden.

View example in new window.

Adding DOM-based event handlers to Menu and MenuItem instances.

All of the events for Menu and MenuItem (including DOM-based events such as "mouseover" or "click") are implemented as instances of Custom Event (YAHOO.util.CustomEvent). Please note: To listen for DOM-based events always use the provided Custom Event-based interface rather than attaching handlers directly to a Menu's DOM elements.

Add event listeners through the subscribe method. The following example demonstrates how to subscribe to the "show" and "hide" events:

1/*
2     Generic event handler used to log info about the DOM events for 
3     the Menu instance.
4*/ 
5 
6function onMenuEvent(p_sType, p_aArgs) { 
7 
8    var oDOMEvent = p_aArgs[0]; 
9 
10    YAHOO.log(("Id: " + this.id + ", " + 
11               "Custom Event Type: " + p_sType + ", " +                   
12               "DOM Event Type: " + oDOMEvent.type),  
13               "info", "example10"); 
14} 
15 
16 
17/*
18     Generic event handler used to log info about the DOM events for 
19     each MenuItem instance.
20*/ 
21 
22function onMenuItemEvent(p_sType, p_aArgs) { 
23 
24    var oDOMEvent = p_aArgs[0]; 
25 
26    YAHOO.log(("Index: " + this.index + ", " + 
27               "Group Index: " + this.groupIndex + ", " + 
28               "Custom Event Type: " + p_sType + ", " +                   
29               "DOM Event Type: " + oDOMEvent.type 
30               ), "info", "example10"); 
31     
32} 
33 
34 
35/*
36     Instantiate a Menu:  The first argument passed to the 
37     constructor is the id of the element in the page 
38     representing the Menu; the second is an object literal 
39     of configuration properties.
40*/ 
41 
42var oMenu = new YAHOO.widget.Menu("basicmenu", { fixedcenter: true }); 
43 
44 
45// Subscribe to the Menu instance's "itemAdded" event 
46 
47oMenu.subscribe("itemAdded", function (p_sType, p_aArgs) { 
48 
49    var oMenuItem = p_aArgs[0]; 
50     
51    /*
52         Subscribe to each MenuItem instance's DOM events as they
53         are added to the Menu instance.
54    */ 
55 
56    oMenuItem.subscribe("mouseover", onMenuItemEvent); 
57    oMenuItem.subscribe("mouseout", onMenuItemEvent); 
58    oMenuItem.subscribe("mousedown", onMenuItemEvent); 
59    oMenuItem.subscribe("mouseup", onMenuItemEvent); 
60    oMenuItem.subscribe("click", onMenuItemEvent); 
61    oMenuItem.subscribe("keydown", onMenuItemEvent); 
62    oMenuItem.subscribe("keyup", onMenuItemEvent); 
63    oMenuItem.subscribe("keypress", onMenuItemEvent); 
64 
65}); 
66 
67 
68//  Subscribe to every DOM event for the Menu instance. 
69 
70oMenu.subscribe("mouseover", onMenuEvent); 
71oMenu.subscribe("mouseout", onMenuEvent); 
72oMenu.subscribe("mousedown", onMenuEvent); 
73oMenu.subscribe("mouseup", onMenuEvent); 
74oMenu.subscribe("click", onMenuEvent); 
75oMenu.subscribe("keydown", onMenuEvent); 
76oMenu.subscribe("keyup", onMenuEvent); 
77oMenu.subscribe("keypress", onMenuEvent); 
78 
79 
80/*
81    Add items to the Menu instance by passing an array of object literals 
82    (each of which represents a set of YAHOO.widget.MenuItem 
83    configuration properties) to the "addItems" method.
84*/ 
85 
86oMenu.addItems([ 
87 
88        "MenuItem 0", 
89 
90        "MenuItem 1", 
91 
92        /*
93             Add a disabled menu item to demonstrate that disabled 
94             items do not respond to DOM events.
95        */ 
96        { text: "MenuItem 2", disabled: true }, 
97 
98        "MenuItem 3", 
99 
100        "MenuItem 4" 
101 
102    ]); 
103 
104 
105/*
106    Since this Menu instance is built completely from script, call the 
107    "render" method passing in the DOM element that it should be 
108    appended to.
109*/ 
110 
111oMenu.render("rendertarget"); 
view plain | print | ?

YUI Logger Output:

Logger Console

INFO0ms (+0) 5:34:44 AM:
global
Logger initialized

Menu Family Examples:

More Menu Family Resources:

Copyright © 2008 Yahoo! Inc. All rights reserved.

Privacy Policy - Terms of Service - Copyright Policy - Job Openings