Tree with mouseover

Built with blockbuilder.org

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">

<title>Tree Example</title>

<style>

.node {
		cursor: pointer;
	}

.node circle {
	  fill: #fff;
	  stroke: steelblue;
	  stroke-width: 3px;
	}

.node text {
	  font: 12px sans-serif;
	}

.link {
	  fill: none;
	  stroke: #ccc;
	  stroke-width: 2px;
	}

/* Tooltip container */
    .tooltip {
        position: relative;
        display: inline-block;
        border-bottom: 1px dotted black; /* If you want dots under the hoverable text */
    }

/* Tooltip text */
    .tooltip .tooltiptext {
        visibility: hidden;
        width: 120px;
        background-color: black;
        color: #fff;
        text-align: center;
        padding: 5px 0;
        border-radius: 6px;

/* Position the tooltip text - see examples below! */
        position: absolute;
        z-index: 1;
    }

/* Show the tooltip text when you mouse over the tooltip container */
    .tooltip:hover .tooltiptext {
        visibility: visible;
    }

</style>

</head>

<body>

<script src="https://d3js.org/d3.v3.min.js"></script>

var treeData = [
  {
    "name": "Top Parent",
    "parent": "null",
    "children": [
      {
        "name": "Level 2: A",
        "parent": "Top Parent",
        "children": [
          {
            "name": "Son of A",
            "parent": "Level 2: A"
          },
          {
            "name": "Daughter of A",
            "parent": "Level 2: A"
          }
        ]
      },
      {
        "name": "Level 2: B",
        "parent": "Top Level"
      }
    ]
  }
];

// ************** Generate the tree diagram	 *****************
var margin = {top: 20, right: 120, bottom: 20, left: 120},
	width = 960 - margin.right - margin.left,
	height = 500 - margin.top - margin.bottom;

var i = 0,
	duration = 750,
	root;

var tree = d3.layout.tree()
	.size([height, width]);

var diagonal = d3.svg.diagonal()
	.projection(function(d) { return [d.y, d.x]; });

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 + ")");

root = treeData[0];
root.x0 = height / 2;
root.y0 = 0;

update(root);

d3.select(self.frameElement).style("height", "500px");

function update(source) {

// Compute the new tree layout.
  var nodes = tree.nodes(root).reverse(),
	  links = tree.links(nodes);

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

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

// Enter any new nodes 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)														//added mouseover function
    .on("mouseover", function(d) {
          var g = d3.select(this); // The node
          // The class is used to remove the additional text later
          var info = g.append('text')
             .classed('info', true)
             .attr('x', 20)
             .attr('y', 10)
             .text('More info');
      })
      .on("mouseout", function() {
          // Remove the info text on mouse out.
          d3.select(this).select('text.info').remove()
        });
    ;

nodeEnter.append("circle")
	  .attr("r", 1e-6)
	  .style("fill", function(d) { return d._children ? "lightsteelblue" : "#fff"; });

nodeEnter.append("text")
	  .attr("x", function(d) { return d.children || d._children ? -13 : 13; })
	  .attr("dy", ".35em")
	  .attr("text-anchor", function(d) { return d.children || d._children ? "end" : "start"; })
	  .text(function(d) { return d.name; })
	  .style("fill-opacity", 1e-6);

// Transition nodes to their new position.
  var nodeUpdate = node.transition()
	  .duration(duration)
	  .attr("transform", function(d) { return "translate(" + d.y + "," + d.x + ")"; });

nodeUpdate.select("circle")
	  .attr("r", 10)
	  .style("fill", function(d) { return d._children ? "lightsteelblue" : "#fff"; });

nodeUpdate.select("text")
	  .style("fill-opacity", 1);

// Transition exiting nodes to the parent's new position.
  var nodeExit = node.exit().transition()
	  .duration(duration)
	  .attr("transform", function(d) { return "translate(" + source.y + "," + source.x + ")"; })
	  .remove();

nodeExit.select("circle")
	  .attr("r", 1e-6);

nodeExit.select("text")
	  .style("fill-opacity", 1e-6);

// Update the links…
  var link = svg.selectAll("path.link")
	  .data(links, function(d) { return d.target.id; });

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

// Transition links to their new position.
  link.transition()
	  .duration(duration)
	  .attr("d", diagonal);

// Transition exiting nodes to the parent's new position.
  link.exit().transition()
	  .duration(duration)
	  .attr("d", function(d) {
		var o = {x: source.x, y: source.y};
		return diagonal({source: o, target: o});
	  })
	  .remove();

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

// 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);
}

</script>

</body>
</html>

Modified http://d3js.org/d3.v3.min.js to a secure url

https://d3js.org/d3.v3.min.js