javascript - D3.js 条形图根据数据的权重或值生成条形颜色

Question

大家好，请帮助我，下面是我的代码。所以实际上我将所有条形颜色都设置为黑色我的要求是动态生成不同值的条形颜色不同的颜色渐变不需要条形之间的空间只需要根据我提供的数据绘制不同颜色的条形图**

var chartdata = [10, 21, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120,
  135, 150, 165, 180, 200, 220, 240, 270, 300, 330, 370, 410
];

var margin = {
  top: 30,
  right: 10,
  bottom: 30,
  left: 50
}

var height = 400 - margin.top - margin.bottom,
  width = 720 - margin.left - margin.right,
  barWidth = 40,
  barOffset = 20;

var dynamicColor;

var yScale = d3.scaleLinear()
  .domain([0, d3.max(chartdata)])
  .range([0, height])

var xScale = d3.scaleBand()
  .domain(d3.range(0, chartdata.length))
  .range([0, width])

var colors = d3.scaleLinear()
  .domain([0, chartdata.length * .33, chartdata.length * .66, chartdata.length])
  .range(['#d6e9c6', '#bce8f1', '#faebcc', '#ebccd1'])

var awesome = d3.select('#bar-chart').append('svg')
  .attr('width', width + margin.left + margin.right)
  .attr('height', height + margin.top + margin.bottom)
  .style('background', '#bce8f1')
  .append('g')
  .attr('transform', 'translate(' + margin.left + ', ' + margin.top + ')')
  .selectAll('rect').data(chartdata)
  .enter().append('rect')
  .attr('width', xScale.bandwidth())
  .attr('x', function(data, i) {
    return xScale(i);
  })
  .attr('height', 0)
  .attr('y', height)
  .on('mouseover', function(data) {
    dynamicColor = this.style.fill;
    d3.select(this)
      .style('fill', '#3c763d')
  })

.on('mouseout', function(data) {
  d3.select(this)
    .style('fill', dynamicColor)
})

awesome.transition()
  .attr('height', function(data) {
    return yScale(data);
  })
  .attr('y', function(data) {
    return height - yScale(data);
  })
  .delay(function(data, i) {
    return i * 20;
  })
  .duration(2000)
  .ease(d3.easeElastic)

var verticalGuideScale = d3.scaleLinear()
  .domain([0, d3.max(chartdata)])
  .range([height, 0])

var vAxis = d3.axisLeft(verticalGuideScale)
  .ticks(10)

var verticalGuide = d3.select('svg').append('g')
vAxis(verticalGuide)
verticalGuide.attr('transform', 'translate(' + margin.left + ', ' + margin.top + ')')
verticalGuide.selectAll('path')
  .styles({
    fill: 'none',
    stroke: "#3c763d"
  })
verticalGuide.selectAll('line')
  .styles({
    stroke: "#3c763d"
  })

var hAxis = d3.axisBottom(xScale)
  .ticks(chartdata.size)

var horizontalGuide = d3.select('svg').append('g')
hAxis(horizontalGuide)
horizontalGuide.attr('transform', 'translate(' + margin.left + ', ' + (height + margin.top) + ')')
horizontalGuide.selectAll('path')
  .styles({
    fill: 'none',
    stroke: "#3c763d"
  })
horizontalGuide.selectAll('line')
  .styles({
    stroke: "#3c763d"
  });

<script src="https://d3js.org/d3.v4.min.js"></script>
<script src="https://d3js.org/d3-selection-multi.v1.min.js"></script>
<div class="someclass">
  <h2>barchart</h2>
  <div id="bar-chart">
  </div>
</div>

Answer 1

您好，请尝试使用以下代码

var chartdata = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120,
  135, 150, 165, 180, 200, 220, 240, 270, 300, 330, 370, 410
];

var margin = {
  top: 30,
  right: 10,
  bottom: 30,
  left: 50
}

var height = 400 - margin.top - margin.bottom,
  width = 720 - margin.left - margin.right,
  barWidth = 40,
  barOffset = 20;

var dynamicColor;

var yScale = d3.scaleLinear()
  .domain([0, d3.max(chartdata)])
  .range([0, height])

var xScale = d3.scaleBand()
  .domain(d3.range(0, chartdata.length))
  .range([0, width])

var colors = d3.scaleLinear()
  .domain([0, chartdata.length * .33, chartdata.length * .66, chartdata.length])
  .range(['#d6e9c6', '#bce8f1', '#faebcc', '#ebccd1'])

var awesome = d3.select('#bar-chart').append('svg')
  .attr('width', width + margin.left + margin.right)
  .attr('height', height + margin.top + margin.bottom)
  .style('background', '#bce8f1')
  .append('g')
  .attr('transform', 'translate(' + margin.left + ', ' + margin.top + ')')
  .selectAll('rect').data(chartdata)
  .enter().append('rect')
  .styles({
    'fill': function(data, i) {
      return colors(i);
    },
    'stroke': '#31708f',
    'stroke-width': '1'
  })
  .attr('width', xScale.bandwidth())
  .attr('x', function(data, i) {
    return xScale(i);
  })
  .attr('height', 0)
  .attr('y', height)
  .on('mouseover', function(data) {
    dynamicColor = this.style.fill;
    d3.select(this)
      .style('fill', '#3c763d')
  })

.on('mouseout', function(data) {
  d3.select(this)
    .style('fill', dynamicColor)
})

awesome.transition()
  .attr('height', function(data) {
    return yScale(data);
  })
  .attr('y', function(data) {
    return height - yScale(data);
  })
  .delay(function(data, i) {
    return i * 20;
  })
  .duration(2000)
  .ease(d3.easeElastic)

var verticalGuideScale = d3.scaleLinear()
  .domain([0, d3.max(chartdata)])
  .range([height, 0])

var vAxis = d3.axisLeft(verticalGuideScale)
  .ticks(10)

var verticalGuide = d3.select('svg').append('g')
vAxis(verticalGuide)
verticalGuide.attr('transform', 'translate(' + margin.left + ', ' + margin.top + ')')
verticalGuide.selectAll('path')
  .styles({
    fill: 'none',
    stroke: "#3c763d"
  })
verticalGuide.selectAll('line')
  .styles({
    stroke: "#3c763d"
  })

var hAxis = d3.axisBottom(xScale)
  .ticks(chartdata.size)

var horizontalGuide = d3.select('svg').append('g')
hAxis(horizontalGuide)
horizontalGuide.attr('transform', 'translate(' + margin.left + ', ' + (height + margin.top) + ')')
horizontalGuide.selectAll('path')
  .styles({
    fill: 'none',
    stroke: "#3c763d"
  })
horizontalGuide.selectAll('line')
  .styles({
    stroke: "#3c763d"
  });

我刚刚添加

 .styles({
    'fill': function(data, i) {
      return colors(i);
    },
    'stroke': '#31708f',
    'stroke-width': '1'
  })