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# 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.

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## 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:

/* Generic event handler used to log info about the DOM events for the Menu instance. */ function onMenuEvent(p_sType, p_aArgs) { var oDOMEvent = p_aArgs[0]; YAHOO.log(("Id: " + this.id + ", " + "Custom Event Type: " + p_sType + ", " + "DOM Event Type: " + oDOMEvent.type), "info", "example10"); } /* Generic event handler used to log info about the DOM events for each MenuItem instance. */ function onMenuItemEvent(p_sType, p_aArgs) { var oDOMEvent = p_aArgs[0]; YAHOO.log(("Index: " + this.index + ", " + "Group Index: " + this.groupIndex + ", " + "Custom Event Type: " + p_sType + ", " + "DOM Event Type: " + oDOMEvent.type ), "info", "example10"); } /* 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("basicmenu", { fixedcenter: true }); // Subscribe to the Menu instance's "itemAdded" event oMenu.subscribe("itemAdded", function (p_sType, p_aArgs) { var oMenuItem = p_aArgs[0]; /* Subscribe to each MenuItem instance's DOM events as they are added to the Menu instance. */ oMenuItem.subscribe("mouseover", onMenuItemEvent); oMenuItem.subscribe("mouseout", onMenuItemEvent); oMenuItem.subscribe("mousedown", onMenuItemEvent); oMenuItem.subscribe("mouseup", onMenuItemEvent); oMenuItem.subscribe("click", onMenuItemEvent); oMenuItem.subscribe("keydown", onMenuItemEvent); oMenuItem.subscribe("keyup", onMenuItemEvent); oMenuItem.subscribe("keypress", onMenuItemEvent); }); // Subscribe to every DOM event for the Menu instance. oMenu.subscribe("mouseover", onMenuEvent); oMenu.subscribe("mouseout", onMenuEvent); oMenu.subscribe("mousedown", onMenuEvent); oMenu.subscribe("mouseup", onMenuEvent); oMenu.subscribe("click", onMenuEvent); oMenu.subscribe("keydown", onMenuEvent); oMenu.subscribe("keyup", onMenuEvent); oMenu.subscribe("keypress", onMenuEvent); /* 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([ "MenuItem 0", "MenuItem 1", /* Add a disabled menu item to demonstrate that disabled items do not respond to DOM events. */ { text: "MenuItem 2", disabled: true }, "MenuItem 3", "MenuItem 4" ]); /* 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:

### Menu Family Examples:

### More Menu Family Resources:

- User's Guide (external)
- API Documentation
- Cheat Sheet PDF (external)

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