CODEWITHSUNDEEP
javascripthtmld3.jstooltipvisualization
FateJudgement
FateJudgement

Reputation: 93

How to add Tooltips to d3 Bar Graph?

I am currently trying to create a bar graph which represents data and is able to change based on a selection, but the bars are hard to read and make understanding the data difficult. I am trying to make a tooltip which shows the number of resources being used per project. Here is my code so far:

<!DOCTYPE html>
<html>
<head>
  <meta>
  <meta http-equiv="refresh" content="90">
  <meta name="description" content="Drawing Shapes w/ D3 - BarChart" />
  <meta charset="utf-8">
  <title>Resources per Project</title>
  <script src="http://d3js.org/d3.v3.min.js" charset="utf-8"></script>

  <style type="text/css">
    h1 {
      font-size: 35px;
      color: darkgrey;
      font-family: Helvetica;
      border-bottom-width: 3px;
      border-bottom-style: dashed;
      border-bottom-color: black;
    }
    
    h2 {
      font-size: 20px;
      color: black;
      font-family: Helvetica;
      text-decoration: underline;
      margin-left: 350px;
      margin-top: 2px; 
    }
  </style>
</head>

<body>
  <h1>Resources used per Project</h1>

  <p>Choose Month:
    <select id="label-option">
      <option value="April">April</option>
      <option value="May">May</option>
      <option value="June">June</option>
      <option value="July">July</option>
      <option value="August">August</option>
      <option value="September">September</option>
    </select>
    <script type="text/javascript">
      var width = 800
      var height = 500
      var emptyVar = 0
      var dataArrayProjects = ['2G', 'An', 'At', 'Au', 'AW', 'Ch', 'CI', 'CN']
      var April = [0.35, 1.66, 3.04, 1.54, 3.45, 2.56, 2.29, 1.37]
      var May = [0.36, 1.69, 3.08, 1.54, 3.62, 2.61, 2.22, 1.44]
      var June = [0.34, 1.7, 3.08, 1.63, 3.66, 2.68, 2.24, 1.51]
      var July = [0.3, 1.72, 3.17, 1.67, 3.56, 2.56, 2.17, 1.44]
      var August = [0.28, 1.79, 3.18, 1.71, 3.62, 2.73, 2.26, 1.54]
      var September = [1.23, 1.74, 3.12, 1.61, 3.66, 2.71, 2.2, 1.48]
      var widthScale = d3.scale.linear()
        .domain([0, 4])
        .range([0, width - 60]);

      d3.select("#label-option").on("change", change)

      function change() {
        var data = April;
        if (this.selectedIndex == 1){
          data = May;
        } else if (this.selectedIndex == 2){
          data = June;
        } else if (this.selectedIndex == 3){
          data = July;
        } else if (this.selectedIndex == 4){
          data = August;
        } else if (this.selectedIndex == 5){
          data = September;
        }
        canvas.selectAll("rect")
        .data(data)
        .attr("width", emptyVar)
        .attr("height", 50)
        .attr("fill", function(d) {
          return color(d)
        })
        .attr("y", function(d, i) {
          return i * 55
        })
       bars.transition()
        .duration(1500)
        .delay(200)
        .attr("width", function(d) {
          return widthScale(d);
        })        
      }

      var heightScale = d3.scale.ordinal()
        .domain(dataArrayProjects)
        .rangePoints([10, height - 85]);

      var color = d3.scale.linear()
        .domain([0, 4])
        .range(["#000066", "#22abff"])

      var axis = d3.svg.axis()
        .ticks("10")
        .scale(widthScale);

      var yAxis = d3.svg.axis()
        .scale(heightScale)
        .orient("left");

      var canvas = d3.select("body")
        .append("svg")
        .attr("width", width)
        .attr("height", height)
        .append("g")
        .attr("transform", "translate(40, 0)");

      var bars = canvas.selectAll("rect")
        .data(April)
        .enter()
        .append("rect")
        .attr("width", emptyVar)
        .attr("height", 50)
        .attr("fill", function(d) {
          return color(d)
        })
        .attr("y", function(d, i) {
          return i * 55
        })

      canvas.append("g")
        .attr("transform", "translate(0, 430)")
        .attr("font-family", "Helvetica")
        .attr("font-size", "15px")
        .call(axis);

      canvas.append("g")
        .attr("font-family", "Helvetica")
        .attr("font-size", "15px")
        .style("fill", "black")
        .attr("class", "y axis")
        .call(yAxis);

      bars.transition()
        .duration(1500)
        .delay(200)
        .attr("width", function(d) {
          return widthScale(d);
        })

var yAxisLine = canvas.append("line")
                  .attr("x1", -3)
                  .attr("y1", 0)
                  .attr("x2", -3)
                  .attr("y2", 436)
                  .attr("stroke-width", 6)
                  .attr("stroke", "black");

    </script>
    <h2>Resources</h2>
</body>

</html>

How do I add a tooltip so that when you hover over one of the bars, the data number it represents is shown.

Upvotes: 0

Views: 4846

Answers (2)

Dipendra Singh
Dipendra Singh

Reputation: 542

There are some plugins which are available like @mbox suggests foxToolTip and d3-tip etc.

Here I am not using any plugin, using CSS and JS to create it CSS

   #myTooltip {
    position: absolute;
    text-align: left;
    width: 80px;
    height: auto;
    min-height: 20px;
    padding: 2px;
    font: 12px sans-serif;
    background-color: rgb(255, 255, 255);
    border: 2px solid rgb(100, 161, 209);
    color: #5E99BD;
    border-radius: 8px 8px 8px 8px;
    pointer-events: none;
    padding: 11px;
   }

   #myTooltip:before {
    box-sizing: border-box;
    display: inline;
    font-size: 18px;
    width: 100%;
    line-height: 1;
    color: rgb(100, 161, 209);
    content: "\25BC";
    position: absolute;
    text-align: center;
    top: 100%;
    left: -2px;
}

JS

You have to add one div which represents tooltip.

var tooplTipDiv = d3.select("body").append("div")   
                .attr("id", "myTooltip")               
                .style("opacity", 0);

And you should provide callbacks for mouseover and mouseout

var bars = canvas.selectAll("rect")
    .data(April)
    .enter()
    .append("rect")
    //add callbacks for onMouseOver and onMouseOut
    .on("mouseover", onMouseOver)                  
    .on("mouseout", onMouseOut)
    .attr("width", emptyVar)
    .attr("height", 50)
    .attr("fill", function(d) {
         return color(d)
    })
    .attr("y", function(d, i) {
        return i * 55
    })

And functions for mouseover and mouseout

function onMouseOver(d){

    var tooltipDiv = d3.select("#myTooltip"); 

    tooltipDiv.transition()        
       .duration(200)      
       .style("opacity", 1);    

    tooltipDiv.html( "your Content")
       .style("left", (parseFloat(widthScale(d))) + "px") 
       .style("cursor", "pointer")
       .style("top", function(d){
           return d3.event.pageY - this.offsetHeight - 17  + "px"
        })
        .style("color", "#333333");        
}

function onMouseOut(d){
    var tooltipDiv = d3.select("#myTooltip"); 
    tooltipDiv.transition()        
          .duration(500)      
          .style("opacity", 0);  
}

If you have still some confusion, let me know, will post full working code.

Upvotes: 1

m fox
m fox

Reputation: 19

You might try foxToolTip.js

https://github.com/MichaelRFox/foxToolTip.js

Then all you would need to do is after you append the rect is add a unique Id

.attr('id', function(d, i) { return 'bar' + i }) .each(function (d, i) { foxToolTip.create('bar' + i, 'whatever html you want' })

Upvotes: 0

Related Questions