数据可视化 D3.js实现力导向图之二（node带文字说明和提示）

来源：互联网发布：java 编译器api 编辑：程序博客网时间：2024/05/17 14:17

从官方下载下的demo，直接加text带文字，始终未能显示出来，但是title却能显示出来，最后经过与网上其他地方做出来的例子用firebug进行跟踪对比，发现能够正确显示title的html里边g标签为node里边包含circle和text(circle、title和text是平级的)，而官方下载下来的demo里边circle包含着text和title，于是把append（“circle”）移到 call(force.drag);之后，用node直接append（“circle”），这样就能正确的显示出text来了（text和circle也是平级的了）.

代码如下：

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title> New Document </title>
<style>
/*
.node {
stroke: #ffffff;
stroke-width: 0.1px;
}
*/
.link {
stroke: #999;
stroke-opacity: .6;
}

</style>
<meta name="Author" content="">
<meta name="Keywords" content="">
<meta name="Description" content="">
</head>

<body>
<script src="d3.min.js"></script>
<script>

var width = 960,
    height = 500;

var colors = d3.scale.category20();

var force = d3.layout.force()
    .charge(-320)
    .linkDistance(100)
    .size([width, height]);

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

d3.json("miserables1.json", function(error, graph) {
force
      .nodes(graph.nodes)
      .links(graph.links)
      .on("tick", tick)
      .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 node = svg.selectAll(".node")
      .data(graph.nodes)
    .enter().append("g")
      .attr("class", "node")
      .call(force.drag);

node.append("circle")
      .attr("r", 10)
      .style("fill", function(d) { return colors(d.group); });

node.append("title")
      .text(function(d) { return d.name});
node.append("text")
    .attr("x", 12)
    .attr("dy", ".35em")
    .text(function(d) { return d.name; });


/*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; });
    node
      .attr("transform", function(d) {
             return "translate(" + d.x + "," + d.y + ")";
      });
});*/
function tick() {//打点更新坐标
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("transform", function(d) {
             return "translate(" + d.x + "," + d.y + ")";
      });
}

});

</script>
</body>
</html>

=================json测试数据================================

{
"nodes":[
    {"name":"11","group":1},
    {"name":"12","group":2},
    {"name":"21","group":3},
    {"name":"22","group":4},
    {"name":"23","group":5}
],
"links":[
    {"source":1,"target":2,"value":1},
    {"source":1,"target":3,"value":1}
]
}

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