Infovis超树节点的需求

我对使用Javascript Infovis Toolkit非常陌生，但是我想做的是创建一个超级树，其中有五个初始节点连接到中间。然后，当用户单击每个子节点时，将出现连接到子节点的新节点(其中6个)。但我不知道该怎么做。下面是我的树代码:

            //now puts in tree and detailer
        var infovis = document.getElementById('infovis');
        var w = infovis.offsetWidth, h = infovis.offsetHeight;
        var ht = new $jit.Hypertree({
            //id of the visualization container  
            injectInto: 'infovis',
            //By setting overridable=true,  
            //Node and Edge global properties can be  
            //overriden for each node/edge.  
            Node: {
                overridable: true,
                'transform': true,
                type: 'circle',
            },
            Edge: {
                overridable: true,
                lineWidth: 5,
                color: "lightgrey"
            },
            //calculate nodes offset  
            offset: 0.2,
            //Change the animation transition type  
            transition: $jit.Trans.Back.easeOut,
            //animation duration (in milliseconds)  
            duration: 1000,
            //Attach event handlers on label creation.  
            onCreateLabel: function (domElement, node) {
                domElement.innerHTML = node.name;
                domElement.style.cursor = "pointer";
                domElement.onclick = function () {
                    ht.onClick(node.id, {
                        hideLabels: false,
                        onComplete: function () {
                            ht.controller.onComplete();
                        }
                    });
                };
            },
            //This method is called when moving/placing a label.  
            //You can add some positioning offsets to the labels here.  
            onPlaceLabel: function (domElement, node) {
                var width = domElement.offsetWidth;
                var intX = parseInt(domElement.style.left);
                intX -= width / 2;
                domElement.style.left = intX + 'px';
            },
            onBeforeCompute: function (node) {
                //fades info out
                $("#inner-details").fadeOut(500);
            },
            onComplete: function () {
                //Make the relations list shown in the right column.  
                var node = ht.graph.getClosestNodeToOrigin("current");
                var html = "<h2>" + node.name + "</h2>";
                html += "<p>" + node.data.Explanation + "</p>"
                $jit.id('inner-details').innerHTML = html;
                //fades info out
                $("#inner-details").fadeIn(500);

            }
        });

        //load JSON graph.  
        ht.loadJSON(json, 2);
        //compute positions and plot  
        ht.refresh();