我正在尝试使用 D3 创建一个强制有向图。我已经创建了一个没有标签的图表,但是一旦我尝试在图表上放置标签,它就会弄乱整个代码并且图表甚至不会出现。我在检查了几个文档后编写了代码,但我不知道在哪里修复它了。如果您能告诉我这段代码的哪一部分出错了,任何熟悉 D3 的人都会感激不尽。
<html>
<head>
<meta charset="utf-8">
<title>D3 v5 force simulation</title>
<style>
text {
font-family: sans-serif;
font-size: 10px;
}
</style>
</head>
<body>
<svg width="500" height="600"></svg>
<script src="https://d3js.org/d3.v5.min.js"></script>
<script>
var nodesData = [
{id:"Korea", "group": 1, "value": 10},
{id:"USA", "group": 1, "value": 5},
{id:"France", "group": 1, "value": 5},
{id:"UK", "group": 1, "value": 5},
{id:"Japan", "group": 1, "value": 20},
{id:"Turkey", "group": 1, "value": 5},
]
var linksData = [
{ "source": 'Korea', "target": 'USA'},
{ "source": 'UK', "target": 'USA' },
{ "source": 'France', "target": 'Turkey' },
{ "source": 'Korea', "target": 'UK' },
{ "source": 'Japan', "target": 'Turkey' },
{ "source": 'Japan', "target": 'Korea' }
]
<---added---->
var svg = d3.select("svg"),
width = +svg.attr("width"),
height = +svg.attr("height");
<---changed---->
var link = svg.append("g")
.selectAll("line")
.data(linksData)
.enter()
.append("line")
.attr("stroke-width", 1)
.attr("stroke", "black");
<---changed---->
var node = svg.append("g")
.selectAll("g")
.data(nodesData)
.enter()
.append("g")
<---changed---->
var circles = node.append("circle")
.data(nodesData)
.attr("r", d => d.value)
.attr("fill", "LightSalmon")
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
<---added---->
var labels = node.append("text")
.text(function(d){return d.id;});
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.id; }))
.force("charge", d3.forceManyBody())
.force("center", d3.forceCenter(200, 150));
simulation
.nodes(nodesData)
.on("tick", ticked);
simulation.force("link")
.links(linksData);
function ticked() {
link
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
}
function dragstarted(d) {
if(!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if(!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
</script>
</body>
</html>
<原代码-无标签的强制有向图> 为了贴标签,我只是改变了几个点。本来node和link是分开设置的,但是组合在一起放label。
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>D3 v5 force simulation</title>
</head>
<body>
<svg width="400" height="300"></svg>
<script src="https://d3js.org/d3.v5.min.js"></script>
<script>
// 1. Data
var nodesData = [
{id:"Korea", "group": 1, "value":10},
{id:"USA", "group": 1,"value":5},
{id:"France", "group": 1,"value":5},
{id:"UK", "group": 1,"value":5},
{id:"Japan", "group": 1,"value":20},
{id:"Turkey", "group": 1,"value":5},
]
var linksData = [
{ "source": 'Korea', "target": 'USA'},
{ "source": 'UK', "target": 'USA' },
{ "source": 'France', "target": 'Turkey' },
{ "source": 'Korea', "target": 'UK' },
{ "source": 'Japan', "target": 'Turkey' },
{ "source": 'Japan', "target": 'Korea' }
]
// 2. svg
var link = d3.select("svg")
.selectAll("line")
.data(linksData)
.enter()
.append("line")
.attr("stroke-width", 1)
.attr("stroke", "black");
var node = d3.select("svg")
.selectAll("circle")
.data(nodesData)
.enter()
.append("circle")
.attr("r", d=> d.value)
.attr("fill", "LightSalmon")
.call(d3.drag()
.on("start", dragstarted)
.on("drag", dragged)
.on("end", dragended));
// 3. forceSimulation
var simulation = d3.forceSimulation()
.force("link", d3.forceLink().id(function(d) { return d.id; }))
.force("charge", d3.forceManyBody())
.force("center", d3.forceCenter(200, 150));
simulation
.nodes(nodesData)
.on("tick", ticked);
simulation.force("link")
.links(linksData);
// 4. forceSimulation
function ticked() {
link
.attr("x1", function(d) { return d.source.x; })
.attr("y1", function(d) { return d.source.y; })
.attr("x2", function(d) { return d.target.x; })
.attr("y2", function(d) { return d.target.y; });
node
.attr("cx", function(d) { return d.x; })
.attr("cy", function(d) { return d.y; });
}
// 5. drag event
function dragstarted(d) {
if(!d3.event.active) simulation.alphaTarget(0.3).restart();
d.fx = d.x;
d.fy = d.y;
}
function dragged(d) {
d.fx = d3.event.x;
d.fy = d3.event.y;
}
function dragended(d) {
if(!d3.event.active) simulation.alphaTarget(0);
d.fx = null;
d.fy = null;
}
</script>
</body>
</html>