如何在D3强制布局中鼠标悬停节点时显示文本

Question

I am trying to display the text when I move the mouse over a node in Force-Directed Graph in D3.js . 当我将鼠标移动到D3.js中的Force-Directed Graph中的节点上时，我试图显示文本。 My problem is that when I move the mouse over any node, all the texts of these nodes are displayed. 我的问题是，当我将鼠标移动到任何节点上时，会显示这些节点的所有文本。 Here is my code: 这是我的代码：

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<style>

.node {
stroke: #fff;
stroke-width: 1.5px;
}

.nodeDetail {
stroke: #fff;
stroke-width: 1.5px;
}

.link {
stroke: #999;
stroke-opacity: .6;
}

node .text {
font: 12px sans-serif;
pointer-events: none;
}

</style>
</head>
<body>
<script src="http://d3js.org/d3.v3.js"></script>
<script src="d3/d3.v3.min.js charset=UTF-8"></script>
<script>
var graph = {
"nodes":[
{"name":"Myriel","group":1},
{"name":"Napoleon","group":1},
{"name":"Mlle.Baptistine","group":1},
{"name":"Mme.Magloire","group":1},
{"name":"CountessdeLo","group":1}
],
"links":[
{"source":1,"target":0,"value":1},
{"source":2,"target":0,"value":8},
{"source":3,"target":0,"value":10},
{"source":3,"target":2,"value":6},
{"source":4,"target":0,"value":1}
]
};
var width = 960,
height = 500;

var color = d3.scale.category20();

var force = d3.layout.force()
.charge(-120)
.linkDistance(30)
.size([width, height]);

var svg = d3.select("body").append("svg")
.attr("width", width)
.attr("height", height);

var drawGraph = function(graph) {
force
  .nodes(graph.nodes)
  .links(graph.links)
  .start();

var link = svg.selectAll(".link")
  .data(graph.links)
  .enter().append("line")
  .attr("class", "link")
  .style("stroke-width", function(d) { return Math.sqrt(d.value); });

var gnodes = svg.selectAll('g.gnode')//('g.gnode')
 .data(graph.nodes)
 .enter()
 .append('g')
 .classed('gnode', true);

var node = gnodes.append("circle")
  .attr("class", "node")
  .attr("r", 5)
  .style("fill", function(d) { return color(d.group); })
  .on("mouseover", function(d)
 {
    d3.select(this).transition()
    .duration(750)
    .attr("r", 15);
    return labels.style("visibility", "visible");
 })
.on("mouseout", function()
 {
 d3.select(this).transition()
.duration(750)
.attr("r", 5);
 return labels.style("visibility", "hidden");//})
 })
 .call(force.drag);

 var labels = gnodes.append("text")
  .text(function(d) { return d.name; })
  .style("visibility", "hidden");

 /*gnodes.append("text")
 .text(function(d) { return d.name; })
 .style("visibility", "hidden");*/

 force.on("tick", function() {
 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; });

 gnodes.attr("transform", function(d) { 
    return 'translate(' + [d.x, d.y] + ')'; 
}); 
});
};

drawGraph(graph);
</script>
</body>
</html>

I tried to do the following codes but it did not work neither: 我试着做以下代码，但它既不起作用：

.on("mouseover", function(d)
 {
    d3.select(this).transition()
    .duration(750)
    .attr("r", 15);
     d3.select(this).append(text)
    .style("visibility", "visible");
 })

How can I display the text that is related to a particular node when I move the mouse over that node? 将鼠标移到该节点上时，如何显示与特定节点相关的文本？ Could anyone please help me solve this problem. 有谁可以帮我解决这个问题。 Thank you in advance. 先感谢您。

Answer 1

This should help: 这应该有所帮助：

.on("mouseover", function(d)
 {
     d3.select(labels[0][d.index]).style("visibility","visible")
 })
.on("mouseout", function(d)
 {
     d3.select(labels[0][d.index]).style("visibility","hidden")
 })

Answer 2

Learning d3 myself here - also thanks very much to juvian 在这里学习d3 - 也非常感谢juvian

I find a more transparent way of coding this would be to say 我发现这是一种更透明的编码方式

.on("mouseover", function(d) { 
  d3.select(this).select("text").style("visibility", "visible") 
})

which selects the object you hover over (a group), selects the text inside it and changes the style to visible. 选择您悬停在其上的对象（一个组），选择其中的文本并将样式更改为可见。 This also avoids the need to make a labels variable which gets a bit messy with the array indexing. 这也避免了制作标签变量的需要，这使得数组索引变得有点混乱。

如何在D3强制布局中鼠标悬停节点时显示文本

问题描述

2 个解决方案

解决方案1
5 已采纳 2014-05-10 18:47:35

解决方案2
2 2014-12-22 12:01:01

如何在D3强制布局中鼠标悬停节点时显示文本

问题描述

2 个解决方案

解决方案1 5 已采纳 2014-05-10 18:47:35

解决方案2 2 2014-12-22 12:01:01

解决方案1
5 已采纳 2014-05-10 18:47:35

解决方案2
2 2014-12-22 12:01:01