source: vbox/trunk/src/libs/dita-ot-1.8.5/doc/treeview.js@ 99507

/*    
This file is part of the DITA Open Toolkit project hosted on
Sourceforge.net. See the accompanying license.txt file for
applicable licenses.  
                                                                                                                                                  
Copyright (c) 2006, Yahoo! Inc. All rights reserved.                                                                                                    
Code licensed under the BSD License:                                                                                                                    
http://developer.yahoo.net/yui/license.txt                                                                                                              
version: 0.10.0                                                                                                                                         
*/ 

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * Contains the tree view state data and the root node.  This is an
 * ordered tree; child nodes will be displayed in the order created, and
 * there currently is no way to change this.
 *
 * @constructor
 * @todo graft (appendBefore, appendAfter)
 * @param {string} id The id of the element that the tree will be inserted
 * into.
 */
YAHOO.widget.TreeView = function(id) {
        if (id) { this.init(id); }
};

/**
 * Count of all nodes in all trees
 * @type int
 */
YAHOO.widget.TreeView.nodeCount = 0;

YAHOO.widget.TreeView.prototype = {

    /**
     * The id of tree container element
     *
     * @type String
     */
    id: null,

     /**
     * Flat collection of all nodes in this tree
     *
     * @type Node[]
     * @private
     */
    _nodes: null,

    /**
     * We lock the tree control while waiting for the dynamic loader to return
     *
     * @type boolean
     */
    locked: false,

    /**
     * The animation to use for expanding children, if any
     *
     * @type string
     * @private
     */
    _expandAnim: null,

    /**
     * The animation to use for collapsing children, if any
     *
     * @type string
     * @private
     */
    _collapseAnim: null,

    /**
     * The current number of animations that are executing
     *
     * @type int
     * @private
     */
    _animCount: 0,

    /**
     * The maximum number of animations to run at one time.
     *
     * @type int
     */
    maxAnim: 2,

    /**
     * Sets up the animation for expanding children
     *
     * @param {string} the type of animation (acceptable constants in YAHOO.widget.TVAnim)
     */
    setExpandAnim: function(type) {
        if (YAHOO.widget.TVAnim.isValid(type)) {
            this._expandAnim = type;
        }
    },

    /**
     * Sets up the animation for collapsing children
     *
     * @param {string} the type of animation (acceptable constants in YAHOO.widget.TVAnim)
     */
    setCollapseAnim: function(type) {
        if (YAHOO.widget.TVAnim.isValid(type)) {
            this._collapseAnim = type;
        }
    },

    /**
     * Perform the expand animation if configured, or just show the
     * element if not configured or too many animations are in progress
     *
     * @param el {HTMLElement} the element to animate
     * @return {boolean} true if animation could be invoked, false otherwise
     */
    animateExpand: function(el) {

        if (this._expandAnim && this._animCount < this.maxAnim) {
            // this.locked = true;
            var tree = this;
            var a = YAHOO.widget.TVAnim.getAnim(this._expandAnim, el, 
                            function() { tree.expandComplete(); });
            if (a) { 
                ++this._animCount;
                a.animate();
            }

            return true;
        }

        return false;
    },

    /**
     * Perform the collapse animation if configured, or just show the
     * element if not configured or too many animations are in progress
     *
     * @param el {HTMLElement} the element to animate
     * @return {boolean} true if animation could be invoked, false otherwise
     */
    animateCollapse: function(el) {

        if (this._collapseAnim && this._animCount < this.maxAnim) {
            // this.locked = true;
            var tree = this;
            var a = YAHOO.widget.TVAnim.getAnim(this._collapseAnim, el, 
                            function() { tree.collapseComplete(); });
            if (a) { 
                ++this._animCount;
                a.animate();
            }

            return true;
        }

        return false;
    },

    /**
     * Function executed when the expand animation completes
     */
    expandComplete: function() {
        --this._animCount;
        // this.locked = false;
    },

    /**
     * Function executed when the collapse animation completes
     */
    collapseComplete: function() {
        --this._animCount;
        // this.locked = false;
    },

    /**
     * Initializes the tree
     *
     * @parm {string} id the id of the element that will hold the tree
     * @private
     */
    init: function(id) {

        this.id = id;
        this._nodes = [];

        // store a global reference
        YAHOO.widget.TreeView.trees[id] = this;

        // Set up the root node
        this.root = new YAHOO.widget.RootNode(this);


    },

    /**
     * Renders the tree boilerplate and visible nodes
     */
    draw: function() {
        var html = this.root.getHtml();
        if(document.getElementById(this.id))
             document.getElementById(this.id).innerHTML = html;
        /*document.getElementById(this.id).innerHTML = html;*/
        this.firstDraw = false;
    },

    /**
     * Nodes register themselves with the tree instance when they are created.
     *
     * @param node {Node} the node to register
     * @private
     */
    regNode: function(node) {
        this._nodes[node.index] = node;
    },

    /**
     * Returns the root node of this tree
     *
     * @return {Node} the root node
     */
    getRoot: function() {
        return this.root;
    },

    /**
     * Configures this tree to dynamically load all child data
     *
     * @param {function} fnDataLoader the function that will be called to get the data
     * @param iconMode {int} configures the icon that is displayed when a dynamic
     * load node is expanded the first time without children.  By default, the 
     * "collapse" icon will be used.  If set to 1, the leaf node icon will be
     * displayed.
     */
    setDynamicLoad: function(fnDataLoader, iconMode) { 
        this.root.setDynamicLoad(fnDataLoader, iconMode);
    },

    /**
     * Expands all child nodes.  Note: this conflicts with the "multiExpand"
     * node property.  If expand all is called in a tree with nodes that
     * do not allow multiple siblings to be displayed, only the last sibling
     * will be expanded.
     */
    expandAll: function() { 
        if (!this.locked) {
            this.root.expandAll(); 
        }
    },

    /**
     * Collapses all expanded child nodes in the entire tree.
     */
    collapseAll: function() { 
        if (!this.locked) {
            this.root.collapseAll(); 
        }
    },

    /**
     * Returns a node in the tree that has the specified index (this index
     * is created internally, so this function probably will only be used
     * in html generated for a given node.)
     *
     * @param {int} nodeIndex the index of the node wanted
     * @return {Node} the node with index=nodeIndex, null if no match
     */
    getNodeByIndex: function(nodeIndex) {
        var n = this._nodes[nodeIndex];
        return (n) ? n : null;
    },

    /**
     * Returns a node that has a matching property and value in the data
     * object that was passed into its constructor.  Provides a flexible
     * way for the implementer to get a particular node.
     *
     * @param {object} property the property to search (usually a string)
     * @param {object} value the value we want to find (usuall an int or string)
     * @return {Node} the matching node, null if no match
     */
    getNodeByProperty: function(property, value) {
        for (var i in this._nodes) {
            var n = this._nodes[i];
            if (n.data && value == n.data[property]) {
                return n;
            }
        }

        return null;
    },

    /**
     * Removes the node and its children, and optionally refreshes the branch 
     * of the tree that was affected.
     * @param {Node} The node to remove
     * @param {boolean} autoRefresh automatically refreshes branch if true
     * @return {boolean} False is there was a problem, true otherwise.
     */
    removeNode: function(node, autoRefresh) { 

        // Don't delete the root node
        if (node.isRoot()) {
            return false;
        }

        // Get the branch that we may need to refresh
        var p = node.parent;
        if (p.parent) {
            p = p.parent;
        }

        // Delete the node and its children
        this._deleteNode(node);

        // Refresh the parent of the parent
        if (autoRefresh && p && p.childrenRendered) {
            p.refresh();
        }

        return true;
    },

    /**
     * Deletes this nodes child collection, recursively.  Also collapses
     * the node, and resets the dynamic load flag.  The primary use for
     * this method is to purge a node and allow it to fetch its data
     * dynamically again.
     * @param {Node} node the node to purge
     */
    removeChildren: function(node) { 
        for (var i=0, len=node.children.length;i<len;++i) {
            this._deleteNode(node.children[i]);
        }

        node.childrenRendered = false;
        node.dynamicLoadComplete = false;
        node.collapse();
    },

    /**
     * Deletes the node and recurses children
     * @private
     */
    _deleteNode: function(node) { 
        var p = node.parent;

        // Remove all the child nodes first
        this.removeChildren(node);

        // Update the parent's collection of children
        var a = [];

        for (i=0, len=p.children.length;i<len;++i) {
            if (p.children[i] != node) {
                a[a.length] = p.children[i];
            }
        }

        p.children = a;

        // reset the childrenRendered flag for the parent
        p.childrenRendered = false;

         // Update the sibling relationship                                                                                                                       
        if (node.previousSibling) {                                                                                                                              
            node.previousSibling.nextSibling = node.nextSibling;                                                                                                   
        }                                                                                                                                                        

        if (node.nextSibling) {                                                                                                                                  
            node.nextSibling.previousSibling = node.previousSibling;                                                                                               
        }

        // Update the tree's node collection 
        delete this._nodes[node.index];
    },

    /**
     * Abstract method that is executed when a node is expanded
     *
     * @param node {Node} the node that was expanded
     */
    onExpand: function(node) { },

    /**
     * Abstract method that is executed when a node is collapsed
     *
     * @param node {Node} the node that was collapsed.
     */
    onCollapse: function(node) { }

};

/**
 * Global cache of tree instances
 *
 * @type Array
 * @private
 */
YAHOO.widget.TreeView.trees = [];

/**
 * Global method for getting a tree by its id.  Used in the generated
 * tree html.
 *
 * @param treeId {String} the id of the tree instance
 * @return {TreeView} the tree instance requested, null if not found.
 */
YAHOO.widget.TreeView.getTree = function(treeId) {
        var t = YAHOO.widget.TreeView.trees[treeId];
        return (t) ? t : null;
};

/**
 * Global method for getting a node by its id.  Used in the generated
 * tree html.
 *
 * @param treeId {String} the id of the tree instance
 * @param nodeIndex {String} the index of the node to return
 * @return {Node} the node instance requested, null if not found
 */
YAHOO.widget.TreeView.getNode = function(treeId, nodeIndex) {
        var t = YAHOO.widget.TreeView.getTree(treeId);
        return (t) ? t.getNodeByIndex(nodeIndex) : null;
};

/**
 * Adds an event.  Replace with event manager when available
 *
 * @param el the elment to bind the handler to
 * @param {string} sType the type of event handler
 * @param {function} fn the callback to invoke
 * @param {boolean} capture if true event is capture phase, bubble otherwise
 */
YAHOO.widget.TreeView.addHandler = function (el, sType, fn, capture) {
        capture = (capture) ? true : false;
        if (el.addEventListener) {
                el.addEventListener(sType, fn, capture);
        } else if (el.attachEvent) {
                el.attachEvent("on" + sType, fn);
        } else {
                el["on" + sType] = fn;
        }
};

/**
 * Attempts to preload the images defined in the styles used to draw the tree by
 * rendering off-screen elements that use the styles.
 */
YAHOO.widget.TreeView.preload = function() {

        var styles = [
                "ygtvtn",       
                "ygtvtm",       
                "ygtvtmh",      
                "ygtvtp",       
                "ygtvtph",      
                "ygtvln",       
                "ygtvlm",       
                "ygtvlmh",      
                "ygtvlp",       
                "ygtvlph",      
                "ygtvloading"
                ];

        var sb = [];
        
        for (var i = 0; i < styles.length; ++i) { 
                sb[sb.length] = '<span class="' + styles[i] + '">&nbsp;</span>';
        }

        var f = document.createElement("div");
        var s = f.style;
        s.position = "absolute";
        s.top = "-1000px";
        s.left = "-1000px";
        f.innerHTML = sb.join("");

        document.body.appendChild(f);
};

YAHOO.widget.TreeView.addHandler(window, 
                "load", YAHOO.widget.TreeView.preload);

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * The base class for all tree nodes.  The node's presentation and behavior in
 * response to mouse events is handled in Node subclasses.
 *
 * @param oData {object} a string or object containing the data that will
 * be used to render this node
 * @param oParent {Node} this node's parent node
 * @param expanded {boolean} the initial expanded/collapsed state
 * @constructor
 */
YAHOO.widget.Node = function(oData, oParent, expanded) {
        if (oParent) { this.init(oData, oParent, expanded); }
};

YAHOO.widget.Node.prototype = {

    /**
     * The index for this instance obtained from global counter in YAHOO.widget.TreeView.
     *
     * @type int
     */
    index: 0,

    /**
     * This node's child node collection.
     *
     * @type Node[] 
     */
    children: null,

    /**
     * Tree instance this node is part of
     *
     * @type TreeView
     */
    tree: null,

    /**
     * The data linked to this node.  This can be any object or primitive
     * value, and the data can be used in getNodeHtml().
     *
     * @type object
     */
    data: null,

    /**
     * Parent node
     *
     * @type Node
     */
    parent: null,

    /**
     * The depth of this node.  We start at -1 for the root node.
     *
     * @type int
     */
    depth: -1,

    /**
     * The href for the node's label.  If one is not specified, the href will
     * be set so that it toggles the node.
     *
     * @type string
     */
    href: null,

    /**
     * The label href target, defaults to current window
     *
     * @type string
     */
    target: "_self",

    /**
     * The node's expanded/collapsed state
     *
     * @type boolean
     */
    expanded: false,

    /**
     * Can multiple children be expanded at once?
     *
     * @type boolean
     */
    multiExpand: true,

    /**
     * Should we render children for a collapsed node?  It is possible that the
     * implementer will want to render the hidden data...  @todo verify that we 
     * need this, and implement it if we do.
     *
     * @type boolean
     */
    renderHidden: false,

    /**
     * This flag is set to true when the html is generated for this node's
     * children, and set to false when new children are added.
     * @type boolean
     */
    childrenRendered: false,

    /**
     * Dynamically loaded nodes only fetch the data the first time they are
     * expanded.  This flag is set to true once the data has been fetched.
     * @type boolean
     */
    dynamicLoadComplete: false,

    /**
     * This node's previous sibling
     *
     * @type Node
     */
    previousSibling: null,

    /**
     * This node's next sibling
     *
     * @type Node
     */
    nextSibling: null,

    /**
     * We can set the node up to call an external method to get the child
     * data dynamically.
     *
     * @type boolean
     * @private
     */
    _dynLoad: false,

    /**
     * Function to execute when we need to get this node's child data.
     *
     * @type function
     */
    dataLoader: null,

    /**
     * This is true for dynamically loading nodes while waiting for the
     * callback to return.
     *
     * @type boolean
     */
    isLoading: false,

    /**
     * The toggle/branch icon will not show if this is set to false.  This
     * could be useful if the implementer wants to have the child contain
     * extra info about the parent, rather than an actual node.
     *
     * @type boolean
     */
    hasIcon: true,

    /**
     * Used to configure what happens when a dynamic load node is expanded
     * and we discover that it does not have children.  By default, it is
     * treated as if it still could have children (plus/minus icon).  Set
     * iconMode to have it display like a leaf node instead.
     * @type int
     */
    iconMode: 0,

    /**
     * The node type
     * @private
     */
    _type: "Node",

    /*
    spacerPath: "http://us.i1.yimg.com/us.yimg.com/i/space.gif",
    expandedText: "Expanded",
    collapsedText: "Collapsed",
    loadingText: "Loading",
    */

    /**
     * Initializes this node, gets some of the properties from the parent
     *
     * @param oData {object} a string or object containing the data that will
     * be used to render this node
     * @param oParent {Node} this node's parent node
     * @param expanded {boolean} the initial expanded/collapsed state
     */
    init: function(oData, oParent, expanded) {
        this.data               = oData;
        this.children   = [];
        this.index              = YAHOO.widget.TreeView.nodeCount;
        ++YAHOO.widget.TreeView.nodeCount;
        this.expanded   = expanded;

        // oParent should never be null except when we create the root node.
        if (oParent) {
            this.tree                   = oParent.tree;
            this.parent                 = oParent;
            this.href                   = "javascript:" + this.getToggleLink();
            this.depth                  = oParent.depth + 1;
            this.multiExpand    = oParent.multiExpand;

            oParent.appendChild(this);
        }
    },

    /**
     * Appends a node to the child collection.
     *
     * @param node {Node} the new node
     * @return {Node} the child node
     * @private
     * @TODO insertBefore, insertAfter
     */
    appendChild: function(node) {
        if (this.hasChildren()) {
            var sib = this.children[this.children.length - 1];
            sib.nextSibling = node;
            node.previousSibling = sib;
        }

        this.tree.regNode(node);
        this.children[this.children.length] = node;
        this.childrenRendered = false;
        return node;

    },

    /**
     * Returns a node array of this node's siblings, null if none.
     *
     * @return Node[]
     */
    getSiblings: function() {
        return this.parent.children;
    },

    /**
     * Shows this node's children
     */
    showChildren: function() {
        if (!this.tree.animateExpand(this.getChildrenEl())) {
            if (this.hasChildren()) {
                this.getChildrenEl().style.display = "";
            }
        }
    },

    /**
     * Hides this node's children
     */
    hideChildren: function() {

        if (!this.tree.animateCollapse(this.getChildrenEl())) {
            this.getChildrenEl().style.display = "none";
        }
    },

    /**
     * Returns the id for this node's container div
     *
     * @return {string} the element id
     */
    getElId: function() {
        return "ygtv" + this.index;
    },

    /**
     * Returns the id for this node's children div
     *
     * @return {string} the element id for this node's children div
     */
    getChildrenElId: function() {
        return "ygtvc" + this.index;
    },

    /**
     * Returns the id for this node's toggle element
     *
     * @return {string} the toggel element id
     */
    getToggleElId: function() {
        return "ygtvt" + this.index;
    },

    /**
     * Returns the id for this node's spacer image.  The spacer is positioned
     * over the toggle and provides feedback for screen readers.
     * @return {string} the id for the spacer image
     */
    /*
    getSpacerId: function() {
        return "ygtvspacer" + this.index;
    }, 
    */

    /**
     * Returns this node's container html element
     * @return {HTMLElement} the container html element
     */
    getEl: function() {
        return document.getElementById(this.getElId());
    },

    /**
     * Returns the div that was generated for this node's children
     * @return {HTMLElement} this node's children div
     */
    getChildrenEl: function() {
        return document.getElementById(this.getChildrenElId());
    },

    /**
     * Returns the element that is being used for this node's toggle.
     * @return {HTMLElement} this node's toggle html element
     */
    getToggleEl: function() {
        return document.getElementById(this.getToggleElId());
    },

    /**
     * Returns the element that is being used for this node's spacer.
     * @return {HTMLElement} this node's spacer html element
     */
    /*
    getSpacer: function() {
        return document.getElementById( this.getSpacerId() ) || {};
    },
    */

    /*
    getStateText: function() {
        if (this.isLoading) {
            return this.loadingText;
        } else if (this.hasChildren(true)) {
            if (this.expanded) {
                return this.expandedText;
            } else {
                return this.collapsedText;
            }
        } else {
            return "";
        }
    },
    */

    /**
     * Generates the link that will invoke this node's toggle method
     * @return {string} the javascript url for toggling this node
     */
    getToggleLink: function() {
        return "YAHOO.widget.TreeView.getNode(\'" + this.tree.id + "\'," + 
            this.index + ").toggle()";
    },

    /**
     * Hides this nodes children (creating them if necessary), changes the
     * toggle style.
     */
    collapse: function() {
        // Only collapse if currently expanded
        if (!this.expanded) { return; }

        // fire the collapse event handler
        var ret = this.tree.onCollapse(this);

        if ("undefined" != typeof ret && !ret) {
            return;
        }

        if (!this.getEl()) {
            this.expanded = false;
            return;
        }

        // hide the child div
        this.hideChildren();
        this.expanded = false;

        if (this.hasIcon) {
            this.getToggleEl().className = this.getStyle();
        }

        // this.getSpacer().title = this.getStateText();

    },

    /**
     * Shows this nodes children (creating them if necessary), changes the
     * toggle style, and collapses its siblings if multiExpand is not set.
     */
    expand: function() {
        // Only expand if currently collapsed.
        if (this.expanded) { return; }

        // fire the expand event handler
        var ret = this.tree.onExpand(this);

        if ("undefined" != typeof ret && !ret) {
            return;
        }

        if (!this.getEl()) {
            this.expanded = true;
            return;
        }

        if (! this.childrenRendered) {
            this.getChildrenEl().innerHTML = this.renderChildren();
        } else {
        }

        this.expanded = true;
        if (this.hasIcon) {
            this.getToggleEl().className = this.getStyle();
        }

        // this.getSpacer().title = this.getStateText();

        // We do an extra check for children here because the lazy
        // load feature can expose nodes that have no children.

        // if (!this.hasChildren()) {
        if (this.isLoading) {
            this.expanded = false;
            return;
        }

        if (! this.multiExpand) {
            var sibs = this.getSiblings();
            for (var i=0; i<sibs.length; ++i) {
                if (sibs[i] != this && sibs[i].expanded) { 
                    sibs[i].collapse(); 
                }
            }
        }

        this.showChildren();
    },

    /**
     * Returns the css style name for the toggle
     *
     * @return {string} the css class for this node's toggle
     */
    getStyle: function() {
        if (this.isLoading) {
            return "ygtvloading";
        } else {
            // location top or bottom, middle nodes also get the top style
            var loc = (this.nextSibling) ? "t" : "l";

            // type p=plus(expand), m=minus(collapase), n=none(no children)
            var type = "n";
            if (this.hasChildren(true) || (this.isDynamic() && !this.getIconMode())) {
            // if (this.hasChildren(true)) {
                type = (this.expanded) ? "m" : "p";
            }

            return "ygtv" + loc + type;
        }
    },

    /**
     * Returns the hover style for the icon
     * @return {string} the css class hover state
     */
    getHoverStyle: function() { 
        var s = this.getStyle();
        if (this.hasChildren(true) && !this.isLoading) { 
            s += "h"; 
        }
        return s;
    },

    /**
     * Recursively expands all of this node's children.
     */
    expandAll: function() { 
        for (var i=0;i<this.children.length;++i) {
            var c = this.children[i];
            if (c.isDynamic()) {
                alert("Not supported (lazy load + expand all)");
                break;
            } else if (! c.multiExpand) {
                alert("Not supported (no multi-expand + expand all)");
                break;
            } else {
                c.expand();
                c.expandAll();
            }
        }
    },

    /**
     * Recursively collapses all of this node's children.
     */
    collapseAll: function() { 
        for (var i=0;i<this.children.length;++i) {
            this.children[i].collapse();
            this.children[i].collapseAll();
        }
    },

    /**
     * Configures this node for dynamically obtaining the child data
     * when the node is first expanded.  Calling it without the callback
     * will turn off dynamic load for the node.
     *
     * @param fmDataLoader {function} the function that will be used to get the data.
     * @param iconMode {int} configures the icon that is displayed when a dynamic
     * load node is expanded the first time without children.  By default, the 
     * "collapse" icon will be used.  If set to 1, the leaf node icon will be
     * displayed.
     */
    setDynamicLoad: function(fnDataLoader, iconMode) { 
        if (fnDataLoader) {
            this.dataLoader = fnDataLoader;
            this._dynLoad = true;
        } else {
            this.dataLoader = null;
            this._dynLoad = false;
        }

        if (iconMode) {
            this.iconMode = iconMode;
        }
    },

    /**
     * Evaluates if this node is the root node of the tree
     *
     * @return {boolean} true if this is the root node
     */
    isRoot: function() { 
        return (this == this.tree.root);
    },

    /**
     * Evaluates if this node's children should be loaded dynamically.  Looks for
     * the property both in this instance and the root node.  If the tree is
     * defined to load all children dynamically, the data callback function is
     * defined in the root node
     *
     * @return {boolean} true if this node's children are to be loaded dynamically
     */
    isDynamic: function() { 
        var lazy = (!this.isRoot() && (this._dynLoad || this.tree.root._dynLoad));
        return lazy;
    },

    getIconMode: function() {
        return (this.iconMode || this.tree.root.iconMode);
    },

    /**
     * Checks if this node has children.  If this node is lazy-loading and the
     * children have not been rendered, we do not know whether or not there
     * are actual children.  In most cases, we need to assume that there are
     * children (for instance, the toggle needs to show the expandable 
     * presentation state).  In other times we want to know if there are rendered
     * children.  For the latter, "checkForLazyLoad" should be false.
     *
     * @param checkForLazyLoad {boolean} should we check for unloaded children?
     * @return {boolean} true if this has children or if it might and we are
     * checking for this condition.
     */
    hasChildren: function(checkForLazyLoad) { 
        return ( this.children.length > 0 || 
                (checkForLazyLoad && this.isDynamic() && !this.dynamicLoadComplete) );
    },

    /**
     * Expands if node is collapsed, collapses otherwise.
     */
    toggle: function() {
        if (!this.tree.locked && ( this.hasChildren(true) || this.isDynamic()) ) {
            if (this.expanded) { this.collapse(); } else { this.expand(); }
        }
    },

    /**
     * Returns the markup for this node and its children.
     *
     * @return {string} the markup for this node and its expanded children.
     */
    getHtml: function() {
        var sb = [];
        sb[sb.length] = '<div class="ygtvitem" id="' + this.getElId() + '">';
        sb[sb.length] = this.getNodeHtml();
        sb[sb.length] = this.getChildrenHtml();
        sb[sb.length] = '</div>';
        return sb.join("");
    },

    /**
     * Called when first rendering the tree.  We always build the div that will
     * contain this nodes children, but we don't render the children themselves
     * unless this node is expanded.
     *
     * @return {string} the children container div html and any expanded children
     * @private
     */
    getChildrenHtml: function() {

        var sb = [];
        sb[sb.length] = '<div class="ygtvchildren"';
        sb[sb.length] = ' id="' + this.getChildrenElId() + '"';
        if (!this.expanded) {
            sb[sb.length] = ' style="display:none;"';
        }
        sb[sb.length] = '>';

        // Don't render the actual child node HTML unless this node is expanded.
        if ( (this.hasChildren(true) && this.expanded) ||
                (this.renderHidden && !this.isDynamic()) ) {
            sb[sb.length] = this.renderChildren();
        }

        sb[sb.length] = '</div>';

        return sb.join("");
    },

    /**
     * Generates the markup for the child nodes.  This is not done until the node
     * is expanded.
     *
     * @return {string} the html for this node's children
     * @private
     */
    renderChildren: function() {


        var node = this;

        if (this.isDynamic() && !this.dynamicLoadComplete) {
            this.isLoading = true;
            this.tree.locked = true;

            if (this.dataLoader) {

                setTimeout( 
                    function() {
                        node.dataLoader(node, 
                            function() { 
                                node.loadComplete(); 
                            });
                    }, 10);
                
            } else if (this.tree.root.dataLoader) {

                setTimeout( 
                    function() {
                        node.tree.root.dataLoader(node, 
                            function() { 
                                node.loadComplete(); 
                            });
                    }, 10);

            } else {
                return "Error: data loader not found or not specified.";
            }

            return "";

        } else {
            return this.completeRender();
        }
    },

    /**
     * Called when we know we have all the child data.
     * @return {string} children html
     */
    completeRender: function() {
        var sb = [];

        for (var i=0; i < this.children.length; ++i) {
            this.children[i].childrenRendered = false;
            sb[sb.length] = this.children[i].getHtml();
        }
        
        this.childrenRendered = true;

        return sb.join("");
    },

    /**
     * Load complete is the callback function we pass to the data provider
     * in dynamic load situations.
     */
    loadComplete: function() {
        this.getChildrenEl().innerHTML = this.completeRender();
        this.dynamicLoadComplete = true;
        this.isLoading = false;
        this.expand();
        this.tree.locked = false;
    },

    /**
     * Returns this node's ancestor at the specified depth.
     *
     * @param {int} depth the depth of the ancestor.
     * @return {Node} the ancestor
     */
    getAncestor: function(depth) {
        if (depth >= this.depth || depth < 0)  {
            return null;
        }

        var p = this.parent;
        
        while (p.depth > depth) {
            p = p.parent;
        }

        return p;
    },

    /**
     * Returns the css class for the spacer at the specified depth for
     * this node.  If this node's ancestor at the specified depth
     * has a next sibling the presentation is different than if it
     * does not have a next sibling
     *
     * @param {int} depth the depth of the ancestor.
     * @return {string} the css class for the spacer
     */
    getDepthStyle: function(depth) {
        return (this.getAncestor(depth).nextSibling) ? 
            "ygtvdepthcell" : "ygtvblankdepthcell";
    },

    /**
     * Get the markup for the node.  This is designed to be overrided so that we can
     * support different types of nodes.
     *
     * @return {string} The HTML that will render this node.
     */
    getNodeHtml: function() { 
        return ""; 
    },

    /**
     * Regenerates the html for this node and its children.  To be used when the
     * node is expanded and new children have been added.
     */
    refresh: function() {
        // this.loadComplete();
        this.getChildrenEl().innerHTML = this.completeRender();

        if (this.hasIcon) {
            var el = this.getToggleEl();
            if (el) {
                el.className = this.getStyle();
            }
        }
    }

};

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * A custom YAHOO.widget.Node that handles the unique nature of 
 * the virtual, presentationless root node.
 *
 * @extends YAHOO.widget.Node
 * @constructor
 */
YAHOO.widget.RootNode = function(oTree) {
        // Initialize the node with null params.  The root node is a
        // special case where the node has no presentation.  So we have
        // to alter the standard properties a bit.
        this.init(null, null, true);
        
        /**
         * For the root node, we get the tree reference from as a param
         * to the constructor instead of from the parent element.
         *
         * @type TreeView
         */
        this.tree = oTree;
};
YAHOO.widget.RootNode.prototype = new YAHOO.widget.Node();

// overrides YAHOO.widget.Node
YAHOO.widget.RootNode.prototype.getNodeHtml = function() { 
        return ""; 
};

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * The default node presentation.  The first parameter should be
 * either a string that will be used as the node's label, or an object
 * that has a string propery called label.  By default, the clicking the
 * label will toggle the expanded/collapsed state of the node.  By
 * changing the href property of the instance, this behavior can be
 * changed so that the label will go to the specified href.
 *
 * @extends YAHOO.widget.Node
 * @constructor
 * @param oData {object} a string or object containing the data that will
 * be used to render this node
 * @param oParent {YAHOO.widget.Node} this node's parent node
 * @param expanded {boolean} the initial expanded/collapsed state
 */
YAHOO.widget.TextNode = function(oData, oParent, expanded) {
    this.type = "TextNode";

        if (oParent) { 
                this.init(oData, oParent, expanded);
                this.setUpLabel(oData);
        }
};

YAHOO.widget.TextNode.prototype = new YAHOO.widget.Node();

/**
 * The CSS class for the label href.  Defaults to ygtvlabel, but can be
 * overridden to provide a custom presentation for a specific node.
 *
 * @type string
 */
YAHOO.widget.TextNode.prototype.labelStyle = "ygtvlabel";

/**
 * The derived element id of the label for this node
 *
 * @type string
 */
YAHOO.widget.TextNode.prototype.labelElId = null;

/**
 * The text for the label.  It is assumed that the oData parameter will
 * either be a string that will be used as the label, or an object that
 * has a property called "label" that we will use.
 *
 * @type string
 */
YAHOO.widget.TextNode.prototype.label = null;

/**
 * Sets up the node label
 * 
 * @param oData string containing the label, or an object with a label property
 */
YAHOO.widget.TextNode.prototype.setUpLabel = function(oData) { 
        if (typeof oData == "string") {
                oData = { label: oData };
        }
        this.label = oData.label;
        
        // update the link
        if (oData.href) {
                this.href = oData.href;
        }

        // set the target
        if (oData.target) {
                this.target = oData.target;
        }

    if (oData.style) {
        this.labelStyle = oData.style;
    }

        this.labelElId = "ygtvlabelel" + this.index;
};

/**
 * Returns the label element
 *
 * @return {object} the element
 */
YAHOO.widget.TextNode.prototype.getLabelEl = function() { 
        return document.getElementById(this.labelElId);
};

// overrides YAHOO.widget.Node
YAHOO.widget.TextNode.prototype.getNodeHtml = function() { 
        var sb = [];

        sb[sb.length] = '<table border="0" cellpadding="0" cellspacing="0">';
        sb[sb.length] = '<tr>';
        
        for (i=0;i<this.depth;++i) {
                // sb[sb.length] = '<td class="ygtvdepthcell">&nbsp;</td>';
                sb[sb.length] = '<td class="' + this.getDepthStyle(i) + '">&nbsp;</td>';
        }

        var getNode = 'YAHOO.widget.TreeView.getNode(\'' +
                                        this.tree.id + '\',' + this.index + ')';

        sb[sb.length] = '<td';
        // sb[sb.length] = ' onselectstart="return false"';
        sb[sb.length] = ' id="' + this.getToggleElId() + '"';
        sb[sb.length] = ' class="' + this.getStyle() + '"';
        if (this.hasChildren(true)) {
                sb[sb.length] = ' onmouseover="this.className=';
                sb[sb.length] = getNode + '.getHoverStyle()"';
                sb[sb.length] = ' onmouseout="this.className=';
                sb[sb.length] = getNode + '.getStyle()"';
        }


        sb[sb.length] = ' onclick="javascript:' + this.getToggleLink() + '">';

    /*
        sb[sb.length] = '<img id="' + this.getSpacerId() + '"';
    sb[sb.length] = ' alt=""';
    sb[sb.length] = ' tabindex=0';
    sb[sb.length] = ' src="' + this.spacerPath + '"';
    sb[sb.length] = ' title="' + this.getStateText() + '"';
    sb[sb.length] = ' class="ygtvspacer"';
    // sb[sb.length] = ' onkeypress="return ' + getNode + '".onKeyPress()"';
    sb[sb.length] = ' />';
    */

        sb[sb.length] = '&nbsp;';

        sb[sb.length] = '</td>';
        sb[sb.length] = '<td>';
        sb[sb.length] = '<a';
        sb[sb.length] = ' id="' + this.labelElId + '"';
        sb[sb.length] = ' class="' + this.labelStyle + '"';
        sb[sb.length] = ' href="' + this.href + '"';
        sb[sb.length] = ' target="' + this.target + '"';
        
        sb[sb.length] = ' onclick="return ' + getNode + '.onLabelClick(' + getNode +')"';
        /*sb[sb.length] = ' onclick="javascript:' + this.getToggleLink() + '.onLabelClick(' + getNode
        +')"';*/

        if (this.hasChildren(true)) {
                sb[sb.length] = ' onmouseover="document.getElementById(\'';
                sb[sb.length] = this.getToggleElId() + '\').className=';
                sb[sb.length] = getNode + '.getHoverStyle()"';
                sb[sb.length] = ' onmouseout="document.getElementById(\'';
                sb[sb.length] = this.getToggleElId() + '\').className=';
                sb[sb.length] = getNode + '.getStyle()"';
        }
        sb[sb.length] = ' >';
        sb[sb.length] = this.label;
        sb[sb.length] = '</a>';
        sb[sb.length] = '</td>';
        sb[sb.length] = '</tr>';
        sb[sb.length] = '</table>';

        return sb.join("");
};

/**
 * Executed when the label is clicked
 * @param me {Node} this node
 * @scope the anchor tag clicked
 * @return false to cancel the anchor click
 */
YAHOO.widget.TextNode.prototype.onLabelClick = function(me) { 
    //return true;
};
/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * A menu-specific implementation that differs from TextNode in that only 
 * one sibling can be expanded at a time.
 * @extends YAHOO.widget.TextNode
 * @constructor
 */
YAHOO.widget.MenuNode = function(oData, oParent, expanded) {
        if (oParent) { 
                this.init(oData, oParent, expanded);
                this.setUpLabel(oData);
        }

    /**
     * Menus usually allow only one branch to be open at a time.
     * @type boolean
     */
        this.multiExpand = false;

};

YAHOO.widget.MenuNode.prototype = new YAHOO.widget.TextNode();

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * This implementation takes either a string or object for the
 * oData argument.  If is it a string, we will use it for the display
 * of this node (and it can contain any html code).  If the parameter
 * is an object, we look for a parameter called "html" that will be
 * used for this node's display.
 *
 * @extends YAHOO.widget.Node
 * @constructor
 * @param oData {object} a string or object containing the data that will
 * be used to render this node
 * @param oParent {YAHOO.widget.Node} this node's parent node
 * @param expanded {boolean} the initial expanded/collapsed state
 * @param hasIcon {boolean} specifies whether or not leaf nodes should
 * have an icon
 */
YAHOO.widget.HTMLNode = function(oData, oParent, expanded, hasIcon) {
    if (oParent) { 
        this.init(oData, oParent, expanded);
        this.initContent(oData, hasIcon);
    }
};

YAHOO.widget.HTMLNode.prototype = new YAHOO.widget.Node();

/**
 * The CSS class for the label href.  Defaults to ygtvlabel, but can be
 * overridden to provide a custom presentation for a specific node.
 *
 * @type string
 */
YAHOO.widget.HTMLNode.prototype.contentStyle = "ygtvhtml";

/**
 * The generated id that will contain the data passed in by the implementer.
 *
 * @type string
 */
YAHOO.widget.HTMLNode.prototype.contentElId = null;

/**
 * The HTML content to use for this node's display
 *
 * @type string
 */
YAHOO.widget.HTMLNode.prototype.content = null;

/**
 * Sets up the node label
 *
 * @param {object} An html string or object containing an html property
 * @param {boolean} hasIcon determines if the node will be rendered with an
 * icon or not
 */
YAHOO.widget.HTMLNode.prototype.initContent = function(oData, hasIcon) { 
    if (typeof oData == "string") {
        oData = { html: oData };
    }

    this.html = oData.html;
    this.contentElId = "ygtvcontentel" + this.index;
    this.hasIcon = hasIcon;
};

/**
 * Returns the outer html element for this node's content
 *
 * @return {HTMLElement} the element
 */
YAHOO.widget.HTMLNode.prototype.getContentEl = function() { 
    return document.getElementById(this.contentElId);
};

// overrides YAHOO.widget.Node
YAHOO.widget.HTMLNode.prototype.getNodeHtml = function() { 
    var sb = [];

    sb[sb.length] = '<table border="0" cellpadding="0" cellspacing="0">';
    sb[sb.length] = '<tr>';
    
    for (i=0;i<this.depth;++i) {
        sb[sb.length] = '<td class="' + this.getDepthStyle(i) + '">&nbsp;</td>';
    }

    if (this.hasIcon) {
        sb[sb.length] = '<td';
        sb[sb.length] = ' id="' + this.getToggleElId() + '"';
        sb[sb.length] = ' class="' + this.getStyle() + '"';
        sb[sb.length] = ' onclick="javascript:' + this.getToggleLink() + '"';
        if (this.hasChildren(true)) {
            sb[sb.length] = ' onmouseover="this.className=';
            sb[sb.length] = 'YAHOO.widget.TreeView.getNode(\'';
            sb[sb.length] = this.tree.id + '\',' + this.index +  ').getHoverStyle()"';
            sb[sb.length] = ' onmouseout="this.className=';
            sb[sb.length] = 'YAHOO.widget.TreeView.getNode(\'';
            sb[sb.length] = this.tree.id + '\',' + this.index +  ').getStyle()"';
        }
        sb[sb.length] = '>&nbsp;</td>';
    }

    sb[sb.length] = '<td';
    sb[sb.length] = ' id="' + this.contentElId + '"';
    sb[sb.length] = ' class="' + this.contentStyle + '"';
    sb[sb.length] = ' >';
    sb[sb.length] = this.html;
    sb[sb.length] = '</td>';
    sb[sb.length] = '</tr>';
    sb[sb.length] = '</table>';

    return sb.join("");
};

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * A static factory class for tree view expand/collapse animations
 *
 * @constructor
 */
YAHOO.widget.TVAnim = function() {
    return {
        /**
         * Constant for the fade in animation
         * 
         * @type string
         */
        FADE_IN: "TVFadeIn",

        /**
         * Constant for the fade out animation
         * 
         * @type string
         */
        FADE_OUT: "TVFadeOut",

        /**
         * Returns a ygAnim instance of the given type
         *
         * @param type {string} the type of animation
         * @param el {HTMLElement} the element to element (probably the children div)
         * @param callback {function} function to invoke when the animation is done.
         * @return {YAHOO.util.Animation} the animation instance
         */
        getAnim: function(type, el, callback) {
            if (YAHOO.widget[type]) {
                return new YAHOO.widget[type](el, callback);
            } else {
                return null;
            }
        },

        /**
         * Returns true if the specified animation class is available
         *
         * @param type {string} the type of animation
         * @return {boolean} true if valid, false if not
         */
        isValid: function(type) {
            return (YAHOO.widget[type]);
        }
    };
} ();

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * A 1/2 second fade-in animation.
 *
 * @constructor
 * @param el {HTMLElement} the element to animate
 * @param callback {function} function to invoke when the animation is finished
 */
YAHOO.widget.TVFadeIn = function(el, callback) {
        /**
         * The element to animate
     * @type HTMLElement
         */
        this.el = el;

        /**
         * the callback to invoke when the animation is complete
         *
         * @type function
         */
        this.callback = callback;

        /**
         * @private
         */
};

/**
 * Performs the animation
 */
YAHOO.widget.TVFadeIn.prototype = {
    animate: function() {
        var tvanim = this;

        var s = this.el.style;
        s.opacity = 0.1;
        s.filter = "alpha(opacity=10)";
        s.display = "";

        // var dur = ( navigator.userAgent.match(/msie/gi) ) ? 0.05 : 0.4;
        var dur = 0.4; 
        // var a = new ygAnim_Fade(this.el, dur, 1);
        // a.setStart(0.1);
        // a.onComplete = function() { tvanim.onComplete(); };

        // var a = new YAHOO.util.Anim(this.el, 'opacity', 0.1, 1);
        var a = new YAHOO.util.Anim(this.el, {opacity: {from: 0.1, to: 1, unit:""}}, dur);
        a.onComplete.subscribe( function() { tvanim.onComplete(); } );
        a.animate();
    },

    /**
     * Clean up and invoke callback
     */
    onComplete: function() {
        this.callback();
    }
};

/* Copyright (c) 2006 Yahoo! Inc. All rights reserved. */

/**
 * A 1/2 second fade out animation.
 *
 * @constructor
 * @param el {HTMLElement} the element to animate
 * @param callback {Function} function to invoke when the animation is finished
 */
YAHOO.widget.TVFadeOut = function(el, callback) {
        /**
         * The element to animate
     * @type HTMLElement
         */
        this.el = el;

        /**
         * the callback to invoke when the animation is complete
         *
         * @type function
         */
        this.callback = callback;

        /**
         * @private
         */
};

/**
 * Performs the animation
 */
YAHOO.widget.TVFadeOut.prototype = {
    animate: function() {
        var tvanim = this;
        // var dur = ( navigator.userAgent.match(/msie/gi) ) ? 0.05 : 0.4;
        var dur = 0.4;
        // var a = new ygAnim_Fade(this.el, dur, 0.1);
        // a.onComplete = function() { tvanim.onComplete(); };

        // var a = new YAHOO.util.Anim(this.el, 'opacity', 1, 0.1);
        var a = new YAHOO.util.Anim(this.el, {opacity: {from: 1, to: 0.1, unit:""}}, dur);
        a.onComplete.subscribe( function() { tvanim.onComplete(); } );
        a.animate();
    },

    /**
     * Clean up and invoke callback
     */
    onComplete: function() {
        var s = this.el.style;
        s.display = "none";
        // s.opacity = 1;
        s.filter = "alpha(opacity=100)";
        this.callback();
    }
};