Question

我目前正在制作一个条形图，它以水平条的形式显示数据，根据放入代码的数据增长。我在这里尝试做的是当文本出现时，文本显示在栏旁边，并随着数据的变化而变化。我已经建立了一个监听器来改变出现的数据我只是不知道如何使数据出现和改变。

＆＃13;

<!DOCTYPE html>
<html>
<head>
  <meta>
  <meta name="description" content="Drawing Shapes w/ D3 - " />
  <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: 0px; 
    }
  </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]

      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 widthScale = d3.scale.linear()
        .domain([0, 4])
        .range([0, width - 60]);

      var heightScale = d3.scale.ordinal()
        .domain(dataArrayProjects)
        .rangePoints([10, height - 85]);

      var color = d3.scale.linear()
        .domain([0, 4])
        .range(["#000033", "#22cdff"])

      var xAxis = d3.svg.axis()
        .ticks("30")
        .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(xAxis);

      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");

      canvas.selectAll("text")
         .data(April)
         .enter()
           .append("text")
              .text(function(d) {
          return April;
     })
         .attr("x", function(d, i) {
        return i * (width / April.length);
     })
         .attr("y", function(d) {
        return height - (April * 4);
     });


    </script>
    <h2>Resources</h2>
</body>
</html>

＆＃13;

正如您所知，如果不知道数据中的确切数字，数据就不易读取且难以理解。如何在条形图旁边显示数字，表示显示的确切数据量。请不要将其他条形图与自己的工具提示联系起来，因为我对d3.js不太了解，也不了解其他图形。

Answer 1

您可以通过首先创建如下标签来实现这一目标：

var texts = canvas.selectAll(".label")//select all DOMs with class label.
        .data(April)
        .enter()
        .append("text")
        .attr("class", "label")
        .attr("x", function(d) {
          return widthScale(d) + 10;//x location of the label
        })
        .attr("fill", function(d) {
          return color(d)
        })
        .attr("y", function(d, i) {
          return (i * 55) + 25; //y location of the label
        })
        .text(function(d, i) {
          return d;
        })

最后在更新部分中，执行以下操作以更新标签。

    texts = canvas.selectAll(".label")
    .data(data)
    .attr("x", function(d) {
      return widthScale(d) + 10;
    })
    .attr("fill", function(d) {
      return color(d)
    })
    .attr("y", function(d, i) {
      return (i * 55) + 25
    })
    .text(function(d, i) {
      return d;
    })

工作代码here

将文字添加到我的栏尾 - D3

1 个答案: