freeCodeCamp/add-a-tooltip-to-a-d3-element.md at 2b9e38a17bd6039a1291f756157c94b3e57955db

Oliver Eyton-Williams 2b9e38a17b

fix: replace .english.md extension with .md

2020-09-29 22:09:04 +02:00

3.9 KiB

Raw Blame History

id, title, challengeType, forumTopicId

id	title	challengeType	forumTopicId
587d7faa367417b2b2512bd6	Add a Tooltip to a D3 Element	6	301470

Description

A tooltip shows more information about an item on a page when the user hovers over that item. There are several ways to add a tooltip to a visualization, this challenge uses the SVG title element. title pairs with the text() method to dynamically add data to the bars.

Instructions

Append a title element under each rect node. Then call the text() method with a callback function so the text displays the data value.

Tests

tests:
  - text: Your code should have 9 <code>title</code> elements.
    testString: assert($('title').length == 9);
  - text: The first <code>title</code> element should have tooltip text of 12.
    testString: assert($('title').eq(0).text() == '12');
  - text: The second <code>title</code> element should have tooltip text of 31.
    testString: assert($('title').eq(1).text() == '31');
  - text: The third <code>title</code> element should have tooltip text of 22.
    testString: assert($('title').eq(2).text() == '22');
  - text: The fourth <code>title</code> element should have tooltip text of 17.
    testString: assert($('title').eq(3).text() == '17');
  - text: The fifth <code>title</code> element should have tooltip text of 25.
    testString: assert($('title').eq(4).text() == '25');
  - text: The sixth <code>title</code> element should have tooltip text of 18.
    testString: assert($('title').eq(5).text() == '18');
  - text: The seventh <code>title</code> element should have tooltip text of 29.
    testString: assert($('title').eq(6).text() == '29');
  - text: The eighth <code>title</code> element should have tooltip text of 14.
    testString: assert($('title').eq(7).text() == '14');
  - text: The ninth <code>title</code> element should have tooltip text of 9.
    testString: assert($('title').eq(8).text() == '9');

Challenge Seed

<style>
  .bar:hover {
    fill: brown;
  }
</style>
<body>
  <script>
    const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];

    const w = 500;
    const h = 100;

    const svg = d3.select("body")
                  .append("svg")
                  .attr("width", w)
                  .attr("height", h);

    svg.selectAll("rect")
       .data(dataset)
       .enter()
       .append("rect")
       .attr("x", (d, i) => i * 30)
       .attr("y", (d, i) => h - 3 * d)
       .attr("width", 25)
       .attr("height", (d, i) => d * 3)
       .attr("fill", "navy")
       .attr("class", "bar")
       // Add your code below this line



       // Add your code above this line

    svg.selectAll("text")
       .data(dataset)
       .enter()
       .append("text")
       .text((d) => d)
       .attr("x", (d, i) => i * 30)
       .attr("y", (d, i) => h - (d * 3 + 3))

  </script>
</body>

Solution

<style>
  .bar:hover {
    fill: brown;
  }
</style>
<body>
  <script>
    const dataset = [12, 31, 22, 17, 25, 18, 29, 14, 9];

    const w = 500;
    const h = 100;

    const svg = d3.select("body")
                  .append("svg")
                  .attr("width", w)
                  .attr("height", h);

    svg.selectAll("rect")
       .data(dataset)
       .enter()
       .append("rect")
       .attr("x", (d, i) => i * 30)
       .attr("y", (d, i) => h - 3 * d)
       .attr("width", 25)
       .attr("height", (d, i) => d * 3)
       .attr("fill", "navy")
       .attr("class", "bar")
       .append("title")
       .text((d) => d)
       

    svg.selectAll("text")
       .data(dataset)
       .enter()
       .append("text")
       .text((d) => d)
       .attr("x", (d, i) => i * 30)
       .attr("y", (d, i) => h - (d * 3 + 3))

  </script>
</body>

3.9 KiB Raw Blame History