我是 java 和 javascript 的新手。我使用 infovis Spacetree 来构建一棵树。我想让父节点的子节点可下载。我的意思是当用户单击父节点 1 的子节点 1 时,它应该下载一个从根目录存储的 pdf 文件。谁能建议我如何做到这一点。这是我在 infovis 中用于 spacetree 的 javascript 代码
var labelType, useGradients, nativeTextSupport, animate;
(function() {
var ua = navigator.userAgent,
iStuff = ua.match(/iPhone/i) || ua.match(/iPad/i),
typeOfCanvas = typeof HTMLCanvasElement,
nativeCanvasSupport = (typeOfCanvas == 'object' || typeOfCanvas == 'function'),
textSupport = nativeCanvasSupport
&& (typeof document.createElement('canvas').getContext('2d').fillText == 'function');
labelType = (!nativeCanvasSupport || (textSupport && !iStuff))? 'Native' : 'HTML';
nativeTextSupport = labelType == 'Native';
useGradients = nativeCanvasSupport;
animate = !(iStuff || !nativeCanvasSupport);
})();
var Log = {
elem: false,
write: function(text){
if (!this.elem)
this.elem = document.getElementById('log');
this.elem.innerHTML = text;
this.elem.style.left = (500 - this.elem.offsetWidth / 2) + 'px';
}
};
function init(){
var json = {
id: "node1",
name: "Stocks",
data: {},
children: [{
id: "node2",
name: "Stock1",
data: {},
children: [{
id: "node3",
name: "A",
data: {},
children: [{
id: "node4",
name: "child 1",
data: {},
children: []
}, {
id: "node5",
name: "child 2",
data: {},
children: []
}, {
id: "node6",
name: "child 3",
data: {},
children: []
}]
}]
}]};
var st = new $jit.ST({
injectInto: 'infovis',
duration: 800,
transition: $jit.Trans.Quart.easeInOut,
levelDistance: 50,
Navigation: {
enable:true,
panning:true
},
Node: {
height: 20,
width: 100,
type: 'rectangle',
color: '#aaa',
overridable: true
},
Edge: {
type: 'bezier',
overridable: true
},
onBeforeCompute: function(node){
Log.write("loading " + node.name);
},
onAfterCompute: function(){
Log.write("done");
},
onCreateLabel: function(label, node){
label.id = node.id;
label.innerHTML = node.name;
label.onclick = function(){
if(normal.checked) {
st.onClick(node.id);
} else {
st.setRoot(node.id, 'animate');
}
};
var style = label.style;
style.width = 60 + 'px';
style.height = 17 + 'px';
style.cursor = 'pointer';
style.color = '#333';
style.fontSize = '0.8em';
style.textAlign= 'center';
style.paddingTop = '3px';
},
onBeforePlotNode: function(node){
if (node.selected) {
node.data.$color = "#ff7";
}
else {
delete node.data.$color;
if(!node.anySubnode("exist")) {
var count = 0;
node.eachSubnode(function(n) { count++; });
node.data.$color = ['#aaa', '#baa', '#caa', '#daa', '#eaa', '#faa'][count];
}
}
},
onBeforePlotLine: function(adj){
if (adj.nodeFrom.selected && adj.nodeTo.selected) {
adj.data.$color = "#eed";
adj.data.$lineWidth = 3;
}
else {
delete adj.data.$color;
delete adj.data.$lineWidth;
}
}
});
st.loadJSON(json);
st.compute();
st.geom.translate(new $jit.Complex(-200, 0), "current");
st.onClick(st.root);
var top = $jit.id('r-top'),
left = $jit.id('r-left'),
bottom = $jit.id('r-bottom'),
right = $jit.id('r-right'),
normal = $jit.id('s-normal');
function changeHandler() {
if(this.checked) {
top.disabled = bottom.disabled = right.disabled = left.disabled = true;
st.switchPosition(this.value, "animate", {
onComplete: function(){
top.disabled = bottom.disabled = right.disabled = left.disabled = false;
}
});
}
};
top.onchange = left.onchange = bottom.onchange = right.onchange = changeHandler;
}
请指导我