Migrating from D3.js v4 to D3.js v7 not working

Question

I want to attempt to convert this force from D3 v4 to v7, but not sure how to go about it.The code conversion what I have done is here. I try to do this< https://observablehq.com/@d3/d3v6-migration-guide>

D3 6.0 is out! It comes with exciting new features and improvements.

It also introduces a few important API changes. But, do not fear: almost all the methods are behaving exactly as they did with v5; just a handful of them are not backwards compatible.

Here's a comprehensive list of the changes you will need to watch for when you upgrade to D3 v6:

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

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

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

text {
  font-family: sans-serif;
  font-size: 10px;
}

</style>
<svg width="500" height="500"></svg>
<script src="https://d3js.org/d3.v7.min.js"></script>

<script>

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

const simulation = d3.forceSimulation()
    .force("link", d3.forceLink().id(function(d) { return d.id; }))
    .force("charge", d3.forceManyBody())
    .force("center", d3.forceCenter(width/3, height / 3));

d3.json("helpme.json", function(error, graph) {
  if (error) throw error;

  const link = svg.append("g")
      .attr("class", "links")
    .selectAll("line")
    .data(graph.links)
    .enter().append("line")
      .attr("stroke-width", function(d) { return Math.sqrt(d[2])*2; });

  const node = svg.append("g")
      .attr("class", "nodes")
    .selectAll("g")
    .data(graph.nodes)
    .enter().append("g")

  const circles = node.append("circle")
    .attr("r", 6)
    .attr("fill", "olive");

  // Create a drag handler and append it to the node object instead
  const drag_handler = d3.drag()
      .on("start", dragstarted)
      .on("drag", dragged)
      .on("end", dragended);

  drag_handler(node);
  
  const lables = node.append("text")
      .text(function(d) {
        return d.id;
      })
      .attr('x', 6)
      .attr('y', 3);

  node.append("title")
      .text(function(d) { return d.id; });

  simulation
      .nodes(graph.nodes)
      .on("tick", ticked);

  simulation.force("link")
      .links(graph.links);

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

function dragged(event,d) {
  d.fx = event.x;
  d.fy = event.y;
}

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

</script>

helpme.json

{
  "nodes": [
    {"id": "A"},
    {"id": "B"},
    {"id": "C"},
    {"id": "D"},
    {"id": "E"},
    {"id": "F"}
  ],
  "links": [
    {"source": "C", "target": "B", "value": 2},
    {"source": "C", "target": "D", "value": 3},
    {"source": "D", "target": "A", "value": 1},
    {"source": "D", "target": "E", "value": 1},
    {"source": "E", "target": "F", "value": 1},
    {"source": "F", "target": "B", "value": 4}
  ]
}

Can someone please help me fix this?Some assistance would be amazing! Danke in Voraus

Answer 1

Have a look at their full migration guide: https://github.com/d3/d3/blob/main/CHANGES.md

I would recommend going major by major.