将图例添加到d3.js树形视图

Question

我正在使用d3.js创建概念图。我正在使用分层视图。根据以下SO问题Add text to connector dynamically in d3js

中给出的解决方案，我已经能够获得有效的代码。

Add text to the connector from input data

我想根据数据中的“类型”键将图例添加到视图中。我正在尝试实现此链接中建议的代码-d3.legend

我的完整代码如下。但这不起作用。我觉得图例代码的更改不正确。请帮我修复它。我对代码添加图例所做的更改是

// Add labels for the nodes
  nodeEnter.append('text')
    .attr("dy", "2em")
    .attr("data-legend",function(d) { return d.name})
    .attr("data-legend-icon", function(d) { return d.name < "N" ? "line" : "circle"})

    var treeData = {
  "name": "File 1",
  "desc": "null",
  "children": [{
    "name": "File 2",
    "desc": "sample",
    "children": [{
      "name": "File 3",
      "desc": "sample",
      "children": [{
        "name": "File 4",
        "type": "data",
        "desc": "sample"
      }]
    }, {
      "name": "File 5",
      "desc": "null",
      "children": [{
        "name": "File 6",
        "type": "data",
        "desc": "sample",
        "children": [{
          "name": "File 7",
          "desc": "sample"
        }, {
          "name": "File 8",
          "type": "data",
          "desc": "sample"
        }]
      }]
    }]
  }]
};

    // Set the dimensions and margins of the diagram
    var margin = {
        top: 20,
        right: 90,
        bottom: 30,
        left: 90
      },
      width = 5000 - margin.left - margin.right,
      height = 500 - margin.top - margin.bottom;

    // append the svg object to the body of the page
    // appends a 'group' element to 'svg'
    // moves the 'group' element to the top left margin
    var svg = d3.select("body").append("svg")
      .attr("width", width + margin.right + margin.left)
      .attr("height", height + margin.top + margin.bottom)
      .append("g")
      .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

    var i = 0,
      duration = 750,
      root;

    // declares a tree layout and assigns the size
    var treemap = d3.tree().size([height, width]);

    // Assigns parent, children, height, depth
    root = d3.hierarchy(treeData, function(d) {
      return d.children;
    });
    root.x0 = height / 2;
    root.y0 = 0;

    // Collapse after the second level
    root.children.forEach(collapse);

    update(root);

    // Collapse the node and all it's children
    function collapse(d) {
      if (d.children) {
        d._children = d.children
        d._children.forEach(collapse)
        d.children = null
      }
    }

    function update(source) {

      // Assigns the x and y position for the nodes
      var treeData = treemap(root);

      // Compute the new tree layout.
      var nodes = treeData.descendants(),
        links = treeData.descendants().slice(1);

      // Normalize for fixed-depth.
      nodes.forEach(function(d) {
        d.y = d.depth * 180
      });

      // ****************** Nodes section ***************************

      // Update the nodes...
      var node = svg.selectAll('g.node')
        .data(nodes, function(d) {
          return d.id || (d.id = ++i);
        });

      // Enter any new modes at the parent's previous position.
      var nodeEnter = node.enter().append('g')
        .attr('class', 'node')
        .attr("transform", function(d) {
          return "translate(" + source.y0 + "," + source.x0 + ")";
        })
        .on('click', click);

      // Add Circle for the nodes
      nodeEnter.filter(function(d) {
          return (!d.data.type || d.data.type !== 'data');
        }).append('circle')
        .attr('class', 'node')
        .attr('r', 1e-6)
        .style("fill", function(d) {
          return d._children ? "lightsteelblue" : "#fff";
        });

      nodeEnter.filter(function(d) {
          return (d.data.type && d.data.type === 'data');
        }).append('rect')
        .attr('class', 'node')
        .attr('width', 20)
        .attr('height', 20)
        .attr('y', -10)
        .attr('x', -10)
        .style("fill", function(d) {
          return d._children ? "lightsteelblue" : "#fff";
        });

      // Add labels for the nodes
      nodeEnter.append('text')
        .attr("dy", "2em")
        .attr("data-legend",function(d) { return d.name})
        .attr("data-legend-icon", function(d) { return d.name < "N" ? "line" : "circle"})
        .attr("x", function(d) {
          return d.children || d._children ? 13 : 13;
        })
        .attr("text-anchor", function(d) {
          return d.children || d._children ? "start" : "start";
        })
        .text(function(d) {
          return d.data.name;
        });

      // UPDATE
      var nodeUpdate = nodeEnter.merge(node);

      // Transition to the proper position for the node
      nodeUpdate.transition()
        .duration(duration)
        .attr("transform", function(d) {
          return "translate(" + d.y + "," + d.x + ")";
        });

      // Update the node attributes and style
      nodeUpdate.select('circle.node')
        .attr('r', 10)
        .style("fill", function(d) {
          return d._children ? "lightsteelblue" : "#fff";
        })
        .attr('cursor', 'pointer');


      // Remove any exiting nodes
      var nodeExit = node.exit().transition()
        .duration(duration)
        .attr("transform", function(d) {
          return "translate(" + source.y + "," + source.x + ")";
        })
        .remove();

      // On exit reduce the node circles size to 0
      nodeExit.select('circle')
        .attr('r', 1e-6);

      // On exit reduce the opacity of text labels
      nodeExit.select('text')
        .style('fill-opacity', 1e-6);

      // ****************** links section ***************************

      // Update the links...
      var link = svg.selectAll('g.link')
        .data(links, function(d) {
          return d.id;
        });

      // Enter any new links at the parent's previous position.
      var linkEnter = link.enter().insert('g', 'g')
        .attr("class", "link");
        
      linkEnter.append('path')
        .attr('d', function(d) {
          var o = {
            x: source.x0,
            y: source.y0
          }
          return diagonal(o, o)
        });

      linkEnter.append('text')
        .text(function(d) {
          //if (d.parent && d.parent.children.length > 1){
           // if (!d.parent.index) d.parent.index = 0;
            //return ++d.parent.index;
            return d.data.desc;
          //}
        })
        .attr('dy', "-1em");

      // UPDATE
      var linkUpdate = linkEnter.merge(link);

      // Transition back to the parent element position
      linkUpdate.select('path').transition()
        .duration(duration)
        .attr('d', function(d) {
          return diagonal(d, d.parent)
        });
        
      linkUpdate.select('text').transition()
        .duration(duration)
        .attr('transform', function(d){
          if (d.parent) {
            return 'translate(' + ((d.parent.y + d.y) / 2) + ',' + ((d.parent.x + d.x) / 2) + ')'
          }
        })
        
      // Remove any exiting links
      link.exit().each(function(d){
        d.parent.index = 0;
      })
      
      var linkExit = link.exit()
        .transition()
        .duration(duration);
      
      linkExit.select('path')
        .attr('d', function(d) {
          var o = {
            x: source.x,
            y: source.y
          }
          return diagonal(o, o)
        })
        
      linkExit.select('text')
        .style('opacity', 0);
      
      linkExit.remove();

      // Store the old positions for transition.
      nodes.forEach(function(d) {
        d.x0 = d.x;
        d.y0 = d.y;
      });

      // Creates a curved (diagonal) path from parent to the child nodes
      function diagonal(s, d) {

        path = `M ${s.y} ${s.x}
            C ${(s.y + d.y) / 2} ${s.x},
              ${(s.y + d.y) / 2} ${d.x},
              ${d.y} ${d.x}`

        return path
      }

      // Toggle children on click.
      function click(d) {
        if (d.children) {
          d._children = d.children;
          d.children = null;
        } else {
          d.children = d._children;
          d._children = null;
        }
        update(d);
      }
    }

    legend = svg.append("g")
    .attr("class","legend")
    .attr("transform","translate(50,30)")
    .style("font-size","12px")
    .call(d3.legend)

  setTimeout(function() { 
    legend
      .style("font-size","20px")
      .attr("data-style-padding",10)
      .call(d3.legend)
  },1000)

<head>
  <meta charset="UTF-8" />
  <script data-require="d3@4.0.0" data-semver="4.0.0" src="https://d3js.org/d3.v4.min.js"></script>
  <script src="d3.legend.js"></script>
  <style>
    .node circle {
      fill: #fff;
      stroke: steelblue;
      stroke-width: 3px;
    }
    
    .node rect {
      fill: #fff;
      stroke: steelblue;
      stroke-width: 3px;
    }
    
    .node text {
      font: 12px sans-serif;
    }
    
    .link path {
      fill: none;
      stroke: #ccc;
      stroke-width: 2px;
    }
    
    .link text {
      font: 12px sans-serif;
    }
    
    .arrow {
      fill: none;
      stroke: #ccc;
      stroke-width: 1px;
    }

    .legend rect {
      fill:white;
      stroke:black;
      opacity:0.8;
    }
  </style>
</head>