MenuBar.js

define([
	"dojo/_base/declare", // declare
	"dojo/keys", // keys.DOWN_ARROW
	"./_MenuBase",
	"dojo/text!./templates/MenuBar.html"
], function(declare, keys, _MenuBase, template){

// module:
//		dijit/MenuBar

	return declare("dijit.MenuBar", _MenuBase, {
		// summary:
		//		A menu bar, listing menu choices horizontally, like the "File" menu in most desktop applications

		templateString: template,

		baseClass: "dijitMenuBar",

		// _isMenuBar: [protected] Boolean
		//		This is a MenuBar widget, not a (vertical) Menu widget.
		_isMenuBar: true,

		postCreate: function(){
			this.inherited(arguments);
			var l = this.isLeftToRight();
			this.connectKeyNavHandlers(
				l ? [keys.LEFT_ARROW] : [keys.RIGHT_ARROW],
				l ? [keys.RIGHT_ARROW] : [keys.LEFT_ARROW]
			);

			// parameter to dijit.popup.open() about where to put popup (relative to this.domNode)
			this._orient = ["below"];
		},

		_moveToPopup: function(/*Event*/ evt){
			// summary:
			//		This handles the down arrow key, opening a submenu if one exists.
			//		Unlike _MenuBase._moveToPopup(), will never move to the next item in the MenuBar.
			// tags:
			//		private

			if(this.focusedChild && this.focusedChild.popup && !this.focusedChild.disabled){
				this.onItemClick(this.focusedChild, evt);
			}
		},

		focusChild: function(item){
			// overload focusChild so that whenever the focus is moved to a new item,
			// check the previous focused whether it has its popup open, if so, after
			// focusing the new item, open its submenu immediately
			var prev_item = this.focusedChild,
				showpopup = prev_item && prev_item.popup && prev_item.popup.isShowingNow;
			this.inherited(arguments);
			if(showpopup && item.popup && !item.disabled){
				this._openPopup(item, true);		// TODO: on down arrow, _openPopup() is called here and in onItemClick()
			}
		},

		_onKeyDown: function(/*Event*/ evt){
			// summary:
			//		Handle keyboard based menu navigation.
			// tags:
			//		protected

			if(evt.ctrlKey || evt.altKey){
				return;
			}

			switch(evt.keyCode){
				case keys.DOWN_ARROW:
					this._moveToPopup(evt);
					evt.stopPropagation();
					evt.preventDefault();
			}
		},

		onItemClick: function(/*dijit/_WidgetBase*/ item, /*Event*/ evt){
			// summary:
			//		Handle clicks on an item.   Also called by _moveToPopup() due to a down-arrow key on the item.
			//		Cancels a dropdown if already open and click is either mouse or space/enter.
			//		Don't close dropdown due to down arrow.
			// tags:
			//		private
			if(item.popup && item.popup.isShowingNow && (!/^key/.test(evt.type) || evt.keyCode !== keys.DOWN_ARROW)){
				item.popup.onCancel();
			}else{
				this.inherited(arguments);
			}
		}
	});

});