问题描述
我想在D3.js中制作决策树，并在链接上添加文字。
I want to make a decision tree in D3.js and to add text on the link.
<!DOCTYPE html>
<meta charset="utf-8">
<body><script src="../d3-master/d3.min.js"></script>
<head><link rel="stylesheet" type="text/css" href="../D3css/D3css.css"></head>
<script>
var margin = {top: 20, right: 20, bottom: 30, left: 40},
width = 960 - margin.left - margin.right,
height = 500 - margin.top - margin.bottom,
rect_width = 90,
rect_height = 20;
var tree = d3.layout.tree()
.size([height * 2, width / 2]);
var diagonal = d3.svg.diagonal()
.projection(function(d) { return [d.x, d.y]; });
var svg = d3.select("body").append("svg")
.attr("width", width + margin.left + margin.right)
.attr("height", height + margin.top + margin.bottom)
.append("g")
.attr("transform", "translate(" + margin.left + "," + margin.top + ")");
d3.json("../data/ID3.json", function(error, root) {
var nodes = tree.nodes(root),
links = tree.links(nodes);
var link = svg.selectAll(".link")
.data(links)
.enter().append("g")
.attr("calss", "link")
.attr("fill", "none");
link.append("path")
.attr("d", diagonal)
.attr("stroke", "lightsteelblue");
link.append("text")
.data(nodes)
.attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; })
.attr("y", -85)
.attr("text-anchor", "middle")
.attr("fill", "black")
.text(function(d) { return d.rule; });
var node = svg.selectAll(".node")
.data(nodes)
.enter().append("g")
.attr("class", "node")
.attr("transform", function(d) { return "translate(" + d.x + "," + d.y + ")"; });
node.append("rect")
.attr("transform", "translate(-42,-8)")
.attr("width", rect_width)
.attr("height", rect_height)
.style("fill", "lightsteelblue");
node.append("text")
.attr("dy", ".31em")
.attr("text-anchor", "middle")
.attr("transform", function(d) { return "translate(" + d.x / 128 + "," + d.y / 128 + ")"; })
.text(function(d) { return d.name; });
});
</script>
右下角的链接上没有文字。
我认为应该使用'节点'数据。
所以，我试图使用'root'数据。
但是，如果我使用'root'数据，我不会一无所获。
There is no text on the link at the bottom right.I think to was due to use 'nodes' data.so, I tried in to use 'root' data.but, I don't come out of nothing if I use 'root' data.
我认为这部分是问题。
link.append（text）
.data（nodes）
link.append("text") .data(nodes)
我该如何修改??
我的数据。
{ "name" : "0", "rule" : "null",
"children" : [{ "name" : "2", "rule" : "sunny",
"children" : [{ "name" : "no(3/100%)", "rule" : "high" },
{ "name" : "yes(2/100%)", "rule" : "normal" }]},
{ "name" : "yes(4/100%)", "rule" : "overcast" },
{ "name" : "3", "rule" : "rainy",
"children" : [{ "name" : "no(2/100%)", "rule" : "TRUE" },
{ "name" : "yes(3/100%)", "rule" : "FALSE" }]}]}
推荐答案
链接，一个人无法访问 dx ， dy ， d.rule ，或类似的领域，因为link与单个数据点无关，但它有源和目标。这意味着应该像这样访问数据： d.source.x ， d.target.y ，等等on。
For links, one can't access d.x, d.y, d.rule, or similar fields, since link is not associated with a single data point, but it has its source and target. This means the data should be accessed like this: d.source.x, d.target.y, and so on.
关键代码段应如下所示：
The key code segment should look like this:
var link = svg.selectAll(".link")
.data(links)
.enter()
.append("g")
.attr("class", "link");
link.append("path")
.attr("fill", "none")
.attr("stroke", "#ff8888")
.attr("stroke-width", "1.5px")
.attr("d", diagonal);
link.append("text")
.attr("font-family", "Arial, Helvetica, sans-serif")
.attr("fill", "Black")
.style("font", "normal 12px Arial")
.attr("transform", function(d) {
return "translate(" +
((d.source.y + d.target.y)/2) + "," +
((d.source.x + d.target.x)/2) + ")";
})
.attr("dy", ".35em")
.attr("text-anchor", "middle")
.text(function(d) {
console.log(d.target.rule);
return d.target.rule;
});
以下是工作示例：
当然，您可以根据需要更改文字颜色，位置等。
Of course, you can change text color, position, etc. to suit your needs.
希望这会有所帮助。
这篇关于我想在D3.js树形图中的链接上添加文本的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！