为什么我的链接不显示？

Question

Below is some code I have used to generate a force directed graph to show the following data.下面是我用来生成力有向图以显示以下数据的一些代码。 The nodes, zoom and pan out features work however the lines wont show between my nodes when there is a link.节点、缩放和平移功能可以工作，但是当有链接时，我的节点之间不会显示线条。 Data in json format: json格式的数据：

{
    "nodes": [
        {
            "id": "100 ladrillos",
            "group": "1",
            "Tags": "[]",
            "Size": "\"1-10"
        },
        {
            "id": "3d business solutions",
            "group": "2",
            "Tags": "[]",
            "Size": "\"1-10"
        },
        {
            "id": "a\u00e3\u0090apps",
            "group": "3",
            "Tags": "[]",
            "Size": "\"1-10"
        },
        {
            "id": "adjoint inc.",
            "group": "4",
            "Tags": "[]",
            "Size": "\"1-10"
        },
        {
            "id": "airbd, inc.",
            "group": "4",
            "Tags": "[]",
            "Size": "\"1-10"
        }
    ],
 "links":[
   {
      "source":"100 ladrillos",
      "target":"3d business solutions",
      "value":20
    },
    {
       "source":"100 ladrillos",
       "target": "a\u00e3\u0090apps",
       "value":10
     },
     {
        "source":"100 ladrillos",
        "target":"adjoint inc.",
        "value":10
      },
     {
        "source":"a\u00e3\u0090apps",
        "target":"airbd, inc.",
        "value":10
      } 
   ]
}

D3 visual code: D3视觉代码：

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

.links line {
  stroke : #999;
  stroke-opacity: 0.6;
}

.nodes circle {
  stroke: black;
  stroke-width: 0px;
}

</style>
<svg width = "1000" height = "1000"></svg>
<script src = "https://d3js.org/d3.v4.min.js"></script>
<script>

//Creating somewhere to put my force directed graph

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

var radius = 15;

d3.json("data.json", function(data) {
  var nodes = data.nodes
  var links = data.links

  var simulation = d3.forceSimulation()
      .nodes(nodes);

  var link_force = d3.forceLink(links)
                        .id(function(d){return d.id;});

  var charge_force = d3.forceManyBody()
      .strength(-100);

  var center_force = d3.forceCenter(width/2,height/2);

  simulation
        .force("charge_force", charge_force)
        .force("center_force", center_force)
        .force("links",link_force)
  ;

  simulation.on("tick",tickActions);

  var g = svg.append("g")
      .attr("class","everything");

  var link = g.append("g")
          .attr("class","links")
        .selectAll("line")
        .data(links)
        .enter().append("line")
          .attr("stroke-width",2)
          .style("stroke",linkColour);

  var node = g.append("g")
          .attr("class","nodes")
          .selectAll("circle")
          .data(nodes)
          .enter()
          .append("circle")
          .attr("r",radius)
          .attr("fill", circleColour);

  var drag_handler = d3.drag()
      .on("start",drag_start)
      .on("drag", drag_drag)
      .on("end",drag_end);

  drag_handler(node);

  var zoom_handler = d3.zoom()
      .on("zoom", zoom_actions);

  zoom_handler(svg);

  function circleColour(d){
    if (d.group == 0){
      return "blue";
    } else {
      return "red";
    }
    }

    function linkColour(d){
        if(d.group == "4"){
            return "green";
        } else {
            return "red";
        }
    }

  function drag_start(d){
  if (!d3.event.active) simulation.alphaTarget(0.3).restart();
    d.fx = d.x
    d.fy = d.y;
  }

  function drag_drag(d){
    d.fx = d3.event.x;
    d.fy = d3.event.y;
  }

  function drag_end(d){
    if (!d3.event.active) simulation.alphaTarget(0);
    d.fx = null;
    d.fy = null;
  }

  function zoom_actions(){
    g.attr("transform", d3.event.transform)

  }

  function tickActions(){
    node
      .attr("cx",function(d) { return d.x;})
      .attr("cy",function(d){ return d.y;});

    link
      .attr("x1", function(d) { return d.source.x;})
      .attr("y1", function(d) { return d.source.y;})
      .attr("x2", function(d) { return d.source.x;})
      .attr("y2", function(d) { return d.source.y;});
  }
});
</script>

Please can someone explain why the links wont show and how I can fix this issue?请有人解释为什么链接不会显示以及我如何解决这个问题？ Thank you.谢谢你。

Answer 1

You're setting the same values for x1 and x2 , the same for y1 and y2 :您为x1和x2设置相同的值，为y1和y2设置相同的值：

link.attr("x1", function(d) { return d.source.x;})
    .attr("y1", function(d) { return d.source.y;})
    .attr("x2", function(d) { return d.source.x;})
    .attr("y2", function(d) { return d.source.y;});

Instead of that, it should be:取而代之的是：

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;})//'target' here
    .attr("y2", function(d) { return d.target.y;});//'target' here

Here is your code with that change (and a smaller SVG):这是带有该更改的代码（以及较小的 SVG）：

 <!DOCTYPE html> <meta charset="utf-8"> <style> .links line { stroke: #999; stroke-opacity: 0.6; } .nodes circle { stroke: black; stroke-width: 0px; } </style> <svg width="500" height="300"></svg> <script src="https://d3js.org/d3.v4.min.js"></script> <script> //Creating somewhere to put my force directed graph var svg = d3.select("svg"), width = +svg.attr("width"), height = +svg.attr("height"); var radius = 15; var data = { "nodes": [{ "id": "100 ladrillos", "group": "1", "Tags": "[]", "Size": "\\"1-10" }, { "id": "3d business solutions", "group": "2", "Tags": "[]", "Size": "\\"1-10" }, { "id": "a\ã\apps", "group": "3", "Tags": "[]", "Size": "\\"1-10" }, { "id": "adjoint inc.", "group": "4", "Tags": "[]", "Size": "\\"1-10" }, { "id": "airbd, inc.", "group": "4", "Tags": "[]", "Size": "\\"1-10" } ], "links": [{ "source": "100 ladrillos", "target": "3d business solutions", "value": 20 }, { "source": "100 ladrillos", "target": "a\ã\apps", "value": 10 }, { "source": "100 ladrillos", "target": "adjoint inc.", "value": 10 }, { "source": "a\ã\apps", "target": "airbd, inc.", "value": 10 } ] }; var nodes = data.nodes var links = data.links var simulation = d3.forceSimulation() .nodes(nodes); var link_force = d3.forceLink(links) .id(function(d) { return d.id; }); var charge_force = d3.forceManyBody() .strength(-100); var center_force = d3.forceCenter(width / 2, height / 2); simulation .force("charge_force", charge_force) .force("center_force", center_force) .force("links", link_force); simulation.on("tick", tickActions); var g = svg.append("g") .attr("class", "everything"); var link = g.append("g") .attr("class", "links") .selectAll("line") .data(links) .enter().append("line") .attr("stroke-width", 2) .style("stroke", linkColour); var node = g.append("g") .attr("class", "nodes") .selectAll("circle") .data(nodes) .enter() .append("circle") .attr("r", radius) .attr("fill", circleColour); var drag_handler = d3.drag() .on("start", drag_start) .on("drag", drag_drag) .on("end", drag_end); drag_handler(node); var zoom_handler = d3.zoom() .on("zoom", zoom_actions); zoom_handler(svg); function circleColour(d) { if (d.group == 0) { return "blue"; } else { return "red"; } } function linkColour(d) { if (d.group == "4") { return "green"; } else { return "red"; } } function drag_start(d) { if (!d3.event.active) simulation.alphaTarget(0.3).restart(); d.fx = dx d.fy = dy; } function drag_drag(d) { d.fx = d3.event.x; d.fy = d3.event.y; } function drag_end(d) { if (!d3.event.active) simulation.alphaTarget(0); d.fx = null; d.fy = null; } function zoom_actions() { g.attr("transform", d3.event.transform) } function tickActions() { node .attr("cx", function(d) { return dx; }) .attr("cy", function(d) { return dy; }); 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; }); } </script>

为什么我的链接不显示？

问题描述

1 个解决方案

解决方案1
1 已采纳 2018-03-04 07:57:12

为什么我的链接不显示？

问题描述

1 个解决方案

解决方案1 1 已采纳 2018-03-04 07:57:12

解决方案1
1 已采纳 2018-03-04 07:57:12