button.js

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        },
        
        
        /**
        * @method _setTarget
        * @description Sets the value of the button's "target" attribute.
        * @protected
        * @param {String} p_sTarget String indicating the value for the button's 
        * "target" attribute.
        */
        _setTarget: function (p_sTarget) {
        
            if (this.get("type") == "link") {
        
                this._button.setAttribute("target", p_sTarget);
            
            }
        
        },
        
        
        /**
        * @method _setChecked
        * @description Sets the value of the button's "target" attribute.
        * @protected
        * @param {Boolean} p_bChecked Boolean indicating the value for  
        * the button's "checked" attribute.
        */
        _setChecked: function (p_bChecked) {
        
            var sType = this.get("type"),
                sTitle;
        
            if (sType == "checkbox" || sType == "radio") {
        
                if (p_bChecked) {
        
                    this.addStateCSSClasses("checked");
                    
                    sTitle = (sType == "radio") ? 
                                this.RADIO_CHECKED_TITLE : 
                                this.CHECKBOX_CHECKED_TITLE;
                
                }
                else {

                    this.removeStateCSSClasses("checked");
        
                    sTitle = (sType == "radio") ? 
                                this.RADIO_DEFAULT_TITLE : 
                                this.CHECKBOX_DEFAULT_TITLE;
                
                }


        		if (!this._hasDefaultTitle) {
        
                	this.set("title", sTitle);
                
                }
        
            }
        
        },
        
        
        /**
        * @method _setMenu
        * @description Sets the value of the button's "menu" attribute.
        * @protected
        * @param {Object} p_oMenu Object indicating the value for the button's 
        * "menu" attribute.
        */
        _setMenu: function (p_oMenu) {

            var bLazyLoad = this.get("lazyloadmenu"),
                oButtonElement = this.get("element"),
                sMenuCSSClassName,
        
                /*
                    Boolean indicating if the value of p_oMenu is an instance 
                    of YAHOO.widget.Menu or YAHOO.widget.Overlay.
                */
        
                bInstance = false,
        

                oMenu,
                oMenuElement,
                oSrcElement,
                aItems,
                nItems,
                oItem,
                i;
        

			function onAppendTo() {

				oMenu.render(oButtonElement.parentNode);
				
				this.removeListener("appendTo", onAppendTo);
			
			}
			
			
			function setMenuContainer() {

				oMenu.cfg.queueProperty("container", oButtonElement.parentNode);
				
				this.removeListener("appendTo", setMenuContainer);
			
			}


			function initMenu() {
		
				var oContainer;
		
				if (oMenu) {

					Dom.addClass(oMenu.element, this.get("menuclassname"));
					Dom.addClass(oMenu.element, "yui-" + this.get("type") + "-button-menu");

					oMenu.showEvent.subscribe(this._onMenuShow, null, this);
					oMenu.hideEvent.subscribe(this._onMenuHide, null, this);
					oMenu.renderEvent.subscribe(this._onMenuRender, null, this);


					if (Menu && oMenu instanceof Menu) {

						if (bLazyLoad) {

							oContainer = this.get("container");

							if (oContainer) {

								oMenu.cfg.queueProperty("container", oContainer);

							}
							else {

								this.on("appendTo", setMenuContainer);

							}

						}

						oMenu.cfg.queueProperty("clicktohide", false);

						oMenu.keyDownEvent.subscribe(this._onMenuKeyDown, this, true);
						oMenu.subscribe("click", this._onMenuClick, this, true);
						oMenu.itemAddedEvent.subscribe(this._onMenuItemAdded, this, true);
		
						oSrcElement = oMenu.srcElement;
		
						if (oSrcElement && oSrcElement.nodeName.toUpperCase() == "SELECT") {
				
							oSrcElement.style.display = "none";
							oSrcElement.parentNode.removeChild(oSrcElement);
		
						}
		
					}
					else if (Overlay && oMenu instanceof Overlay) {
		
						if (!m_oOverlayManager) {
		
							m_oOverlayManager = new YAHOO.widget.OverlayManager();
						
						}
						
						m_oOverlayManager.register(oMenu);
						
					}
		
		
					this._menu = oMenu;

		
					if (!bInstance && !bLazyLoad) {
		
						if (Dom.inDocument(oButtonElement)) {
	
							oMenu.render(oButtonElement.parentNode);
						
						}
						else {
		
							this.on("appendTo", onAppendTo);
						
						}
					
					}
		
				}
		
			}

        
            if (Overlay) {
        
				if (Menu) {
				
					sMenuCSSClassName = Menu.prototype.CSS_CLASS_NAME;
				
				}
			
				if (p_oMenu && Menu && (p_oMenu instanceof Menu)) {
			
					oMenu = p_oMenu;
					aItems = oMenu.getItems();
					nItems = aItems.length;
					bInstance = true;
			
			
					if (nItems > 0) {
			
						i = nItems - 1;
			
						do {
			
							oItem = aItems[i];
			
							if (oItem) {
			
								oItem.cfg.subscribeToConfigEvent("selected", 
									this._onMenuItemSelected, oItem, this);
			
							}
			
						}
						while (i--);
			
					}
			
					initMenu.call(this);
			
				}
				else if (Overlay && p_oMenu && (p_oMenu instanceof Overlay)) {
			
					oMenu = p_oMenu;
					bInstance = true;
			
					oMenu.cfg.queueProperty("visible", false);
			
					initMenu.call(this);
			
				}
				else if (Menu && Lang.isArray(p_oMenu)) {

					oMenu = new Menu(Dom.generateId(), { lazyload: bLazyLoad, itemdata: p_oMenu });
						
					this._menu = oMenu;
			
					this.on("appendTo", initMenu);
			
				}
				else if (Lang.isString(p_oMenu)) {
			
					oMenuElement = Dom.get(p_oMenu);
			
					if (oMenuElement) {
			
						if (Menu && Dom.hasClass(oMenuElement, sMenuCSSClassName) || 
							oMenuElement.nodeName.toUpperCase() == "SELECT") {
				
							oMenu = new Menu(p_oMenu, { lazyload: bLazyLoad });
				
							initMenu.call(this);
				
						}
						else if (Overlay) {
			
							oMenu = new Overlay(p_oMenu, { visible: false });
				
							initMenu.call(this);
				
						}
			
					}
			
				}
				else if (p_oMenu && p_oMenu.nodeName) {
			
					if (Menu && Dom.hasClass(p_oMenu, sMenuCSSClassName) || 
							p_oMenu.nodeName.toUpperCase() == "SELECT") {
			
						oMenu = new Menu(p_oMenu, { lazyload: bLazyLoad });
					
						initMenu.call(this);
			
					}
					else if (Overlay) {
			
						if (!p_oMenu.id) {
						
							Dom.generateId(p_oMenu);
						
						}
			
						oMenu = new Overlay(p_oMenu, { visible: false });
			
						initMenu.call(this);
					
					}
				
				}
            
            }
        
        },
        
        
        /**
        * @method _setOnClick
        * @description Sets the value of the button's "onclick" attribute.
        * @protected
        * @param {Object} p_oObject Object indicating the value for the button's 
        * "onclick" attribute.
        */
        _setOnClick: function (p_oObject) {
        
            /*
                Remove any existing listeners if a "click" event handler 
                has already been specified.
            */
        
            if (this._onclickAttributeValue && 
                (this._onclickAttributeValue != p_oObject)) {
        
                this.removeListener("click", this._onclickAttributeValue.fn);
        
                this._onclickAttributeValue = null;
        
            }
        
        
            if (!this._onclickAttributeValue && 
                Lang.isObject(p_oObject) && 
                Lang.isFunction(p_oObject.fn)) {
        
                this.on("click", p_oObject.fn, p_oObject.obj, p_oObject.scope);
        
                this._onclickAttributeValue = p_oObject;
        
            }
        
        },
        
        
        /**
        * @method _setSelectedMenuItem
        * @description Sets the value of the button's 
        * "selectedMenuItem" attribute.
        * @protected
        * @param {Number} p_nIndex Number representing the index of the item 
        * in the button's menu that is currently selected.
        */
        _setSelectedMenuItem: function (p_nIndex) {

            var oMenu = this._menu,
                oMenuItem;


            if (Menu && oMenu && oMenu instanceof Menu) {

                oMenuItem = oMenu.getItem(p_nIndex);
                

                if (oMenuItem && !oMenuItem.cfg.getProperty("selected")) {
                
                    oMenuItem.cfg.setProperty("selected", true);
                
                }
            
            }

        },
        
        
        // Protected methods

        
        
        /**
        * @method _isActivationKey
        * @description Determines if the specified keycode is one that toggles  
        * the button's "active" state.
        * @protected
        * @param {Number} p_nKeyCode Number representing the keycode to 
        * be evaluated.
        * @return {Boolean}
        */
        _isActivationKey: function (p_nKeyCode) {
        
            var sType = this.get("type"),
                aKeyCodes = (sType == "checkbox" || sType == "radio") ? 
                    this.CHECK_ACTIVATION_KEYS : this.ACTIVATION_KEYS,
        
                nKeyCodes = aKeyCodes.length,
                bReturnVal = false,
                i;
        

            if (nKeyCodes > 0) {
        
                i = nKeyCodes - 1;
        
                do {
        
                    if (p_nKeyCode == aKeyCodes[i]) {
        
                        bReturnVal = true;
                        break;
        
                    }
        
                }
                while (i--);
            
            }
            
            return bReturnVal;
        
        },
        
        
        /**
        * @method _isSplitButtonOptionKey
        * @description Determines if the specified keycode is one that toggles  
        * the display of the split button's menu.
        * @protected
        * @param {Event} p_oEvent Object representing the DOM event object  
        * passed back by the event utility (YAHOO.util.Event).
        * @return {Boolean}
        */
        _isSplitButtonOptionKey: function (p_oEvent) {

			var bShowMenu = (Event.getCharCode(p_oEvent) == 40);


			var onKeyPress = function (p_oEvent) {

				Event.preventDefault(p_oEvent);

				this.removeListener("keypress", onKeyPress);
			
			};


			// Prevent the browser from scrolling the window
			if (bShowMenu) {

				if (UA.opera) {
	
					this.on("keypress", onKeyPress);
	
				}

				Event.preventDefault(p_oEvent);
			}

            return bShowMenu;
        
        },
        
        
        /**
        * @method _addListenersToForm
        * @description Adds event handlers to the button's form.
        * @protected
        */
        _addListenersToForm: function () {
        
            var oForm = this.getForm(),
                onFormKeyPress = YAHOO.widget.Button.onFormKeyPress,
                bHasKeyPressListener,
                oSrcElement,
                aListeners,
                nListeners,
                i;
        
        
            if (oForm) {
        
                Event.on(oForm, "reset", this._onFormReset, null, this);
                Event.on(oForm, "submit", this._onFormSubmit, null, this);