如何设置 D3 Zoom Packed Circle 孩子的颜色

Question

我想在 D3 的压缩圆图中设置子圆的单独颜色。我还希望大小的文本出现在名称文本下。我如何实现这一目标？我在 json 中添加了颜色代码，示例如下。 JSfiddle 的链接是https://jsfiddle.net/smitty1788/9fw51gL1/1/

 {
        "name": "Maryland",
        "children": [{
            "name": "Montgomery",
            "children": [{
                "name": "French",
                "size": 600,
                "fill":"#105908"
            }, {
                "name": "Italian",
                "size": 700,
                "fill":"#59084e"
            }, {
                "name": "Laotian",
                "size": 800,
                "fill":"#f45333"
            }, {
                "name": "African Languages",
                "size": 900,
                "fill":"#fFF000"
            }]
        }

这是 d3 脚本

<script src="https://d3js.org/d3.v4.min.js"></script>
<script>

var svg = d3.select("svg"),
    margin = 20,
    diameter = +svg.attr("width"),
    g = svg.append("g").attr("transform", "translate(" + diameter / 2 + "," + diameter / 2 + ")");

var color = d3.scaleLinear()
    .domain([-1, 5])
    .range(["hsl(152,80%,80%)", "hsl(228,30%,40%)"])
    .interpolate(d3.interpolateHcl);

var pack = d3.pack()
    .size([diameter - margin, diameter - margin])
    .padding(2);

d3.json("/flare.json", function(error, root) {
  if (error) throw error;

  root = d3.hierarchy(root)
      .sum(function(d) { return d.size; })
     .sort(function(a, b) { return b.value - a.value; });

  var focus = root,
      nodes = pack(root).descendants(),
      view;

  var circle = g.selectAll("circle")
    .data(nodes)
    .enter().append("circle")
      .attr("class", function(d) { return d.parent ? d.children ? "node" : "node node--leaf" : "node node--root"; })
      .style("fill", function(d) { return d.children ? color(d.depth) : null; })
      .on("click", function(d) { if (focus !== d) zoom(d),      d3.event.stopPropagation(); });

  var text = g.selectAll("text")
    .data(nodes)
    .enter().append("text")
      .attr("class", "label")
      .style("fill-opacity", function(d) { return d.parent === root ? 1 : 0; })
      .style("display", function(d) { return d.parent === root ? "inline" : "none"; })
      .text(function(d) { return d.data.name; });

  var node = g.selectAll("circle,text");

  svg
      .style("background", color(-1))
      .on("click", function() { zoom(root); });

  zoomTo([root.x, root.y, root.r * 2 + margin]);

  function zoom(d) {
    var focus0 = focus; focus = d;

    var transition = d3.transition()
        .duration(d3.event.altKey ? 7500 : 750)
        .tween("zoom", function(d) {
          var i = d3.interpolateZoom(view, [focus.x, focus.y, focus.r * 2 +    margin]);
          return function(t) { zoomTo(i(t)); };
        });

    transition.selectAll("text")
      .filter(function(d) { return d.parent === focus || this.style.display === "inline"; })
        .style("fill-opacity", function(d) { return d.parent === focus ? 1 : 0; })
        .on("start", function(d) { if (d.parent === focus) this.style.display = "inline"; })
        .on("end", function(d) { if (d.parent !== focus) this.style.display = "none"; });
  }

  function zoomTo(v) {
    var k = diameter / v[2]; view = v;
    node.attr("transform", function(d) { return "translate(" + (d.x - v[0]) * k + "," + (d.y - v[1]) * k + ")"; });
    circle.attr("r", function(d) { return d.r * k; });
  }
});

</script>

感谢您的帮助！

Answer 1

为没有孩子的圈子返回d.data.fill，而不是null：

.style("fill", function(d) { return d.children ? color(d.depth) : d.data.fill; })

这是你更新的小提琴（你的彩色圆圈在最右边）：https://jsfiddle.net/jv4ku850/