条形图中每个条形的不同颜色； 图表JS

Question

我在我正在处理的项目中使用 ChartJS，我需要为条形图中的每个条使用不同的颜色。

以下是条形图数据集的示例：

var barChartData = {
  labels: ["001", "002", "003", "004", "005", "006", "007"],
  datasets: [{
    label: "My First dataset",
    fillColor: "rgba(220,220,220,0.5)", 
    strokeColor: "rgba(220,220,220,0.8)", 
    highlightFill: "rgba(220,220,220,0.75)",
    highlightStroke: "rgba(220,220,220,1)",
    data: [20, 59, 80, 81, 56, 55, 40]
  }]
};

有没有办法把每个条都涂成不同的颜色？

Answer 1

从 v2 开始，您可以通过backgroundColor属性简单地指定一个值数组以对应于每个条的颜色：

datasets: [{
  label: "My First dataset",
  data: [20, 59, 80, 81, 56, 55, 40],
  backgroundColor: ["red", "blue", "green", "blue", "red", "blue"], 
}],

---

这也适用于borderColor 、 hoverBackgroundColor 、 hoverBorderColor 。

从条形图数据集属性的文档中：

某些属性可以指定为数组。 如果这些设置为数组值，则第一个值适用于第一个柱线，第二个值适用于第二个柱线，依此类推。

Answer 2

解决方法：调用update方法设置新值：

var barChartData = {
    labels: ["January", "February", "March"],
    datasets: [
        {
            label: "My First dataset",
            fillColor: "rgba(220,220,220,0.5)", 
            strokeColor: "rgba(220,220,220,0.8)", 
            highlightFill: "rgba(220,220,220,0.75)",
            highlightStroke: "rgba(220,220,220,1)",
            data: [20, 59, 80]
        }
    ]
};

window.onload = function(){
    var ctx = document.getElementById("mycanvas").getContext("2d");
    window.myObjBar = new Chart(ctx).Bar(barChartData, {
          responsive : true
    });

    //nuevos colores
    myObjBar.datasets[0].bars[0].fillColor = "green"; //bar 1
    myObjBar.datasets[0].bars[1].fillColor = "orange"; //bar 2
    myObjBar.datasets[0].bars[2].fillColor = "red"; //bar 3
    myObjBar.update();
}

Answer 3

在查看 Chart.Bar.js 文件后，我设法找到了解决方案。 我使用这个函数来生成随机颜色：

function getRandomColor() {
    var letters = '0123456789ABCDEF'.split('');
    var color = '#';
    for (var i = 0; i < 6; i++ ) {
        color += letters[Math.floor(Math.random() * 16)];
    }
    return color;
}

我已经将它添加到文件的末尾，我在“fillColor:”下调用了这个函数

helpers.each(dataset.data,function(dataPoint,index){
                    //Add a new point for each piece of data, passing any required data to draw.

所以现在看起来像这样：

helpers.each(dataset.data,function(dataPoint,index){
                    //Add a new point for each piece of data, passing any required data to draw.

                    datasetObject.bars.push(new this.BarClass({
                        value : dataPoint,
                        label : data.labels[index],
                        datasetLabel: dataset.label,
                        strokeColor : dataset.strokeColor,
                        fillColor : getRandomColor(),
                        highlightFill : dataset.highlightFill || dataset.fillColor,
                        highlightStroke : dataset.highlightStroke || dataset.strokeColor
                    }));
                },this);

它的工作原理我为每个条形获得不同的颜色。

Answer 4

如果您查看基于 Chart.js 的库“ ChartNew ”，您可以通过将值作为数组传递来实现这一点，如下所示：

var data = {
    labels: ["Batman", "Iron Man", "Captain America", "Robin"],
    datasets: [
        {
            label: "My First dataset",
            fillColor: ["rgba(220,220,220,0.5)", "navy", "red", "orange"],
            strokeColor: "rgba(220,220,220,0.8)",
            highlightFill: "rgba(220,220,220,0.75)",
            highlightStroke: "rgba(220,220,220,1)",
            data: [2000, 1500, 1750, 50]
        }
    ]
};

Answer 5

您可以调用此函数为每个条形生成随机颜色

var randomColorGenerator = function () { 
    return '#' + (Math.random().toString(16) + '0000000').slice(2, 8); 
};

var barChartData = {
        labels: ["001", "002", "003", "004", "005", "006", "007"],
        datasets: [
            {
                label: "My First dataset",
                fillColor: randomColorGenerator(), 
                strokeColor: randomColorGenerator(), 
                highlightFill: randomColorGenerator(),
                highlightStroke: randomColorGenerator(),
                data: [20, 59, 80, 81, 56, 55, 40]
            }
        ]
    };

Answer 6

在这里，我通过创建两个函数解决了这个问题。

1. dynamicColors() 生成随机颜色

function dynamicColors() {
    var r = Math.floor(Math.random() * 255);
    var g = Math.floor(Math.random() * 255);
    var b = Math.floor(Math.random() * 255);
    return "rgba(" + r + "," + g + "," + b + ", 0.5)";
}

2. poolColors() 创建颜色数组

function poolColors(a) {
    var pool = [];
    for(i = 0; i < a; i++) {
        pool.push(dynamicColors());
    }
    return pool;
}

然后，通过它

datasets: [{
    data: arrData,
    backgroundColor: poolColors(arrData.length),
    borderColor: poolColors(arrData.length),
    borderWidth: 1
}]

Answer 7

截至 2019 年 8 月，Chart.js 现在内置了此功能。

您只需要为 backgroundColor 提供一个数组。

示例取自https://www.chartjs.org/docs/latest/getting-started/

前：

  data: {
        labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'],
        datasets: [{
            label: 'My First dataset',
            backgroundColor: 'rgb(255, 99, 132)',
            borderColor: 'rgb(255, 99, 132)',
            data: [0, 10, 5, 2, 20, 30, 45]
        }]
    },

后：

  data: {
        labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'],
        datasets: [{
            label: 'My First dataset',
            backgroundColor: ['rgb(255, 99, 132)','rgb(0, 255, 0)','rgb(255, 99, 132)','rgb(128, 255, 0)','rgb(0, 255, 255)','rgb(255, 255, 0)','rgb(255, 255, 128)'],
            borderColor: 'rgb(255, 99, 132)',
            data: [0, 10, 5, 2, 20, 30, 45]
        }]
    },

我刚刚测试了这个方法并且它有效。 每个条形都有不同的颜色。

Answer 8

生成随机颜色；

function getRandomColor() {
    var letters = '0123456789ABCDEF'.split('');
    var color = '#';
    for (var i = 0; i < 6; i++) {
        color += letters[Math.floor(Math.random() * 16)];
    }
    return color;
}

并为每个记录调用它；

function getRandomColorEachEmployee(count) {
    var data =[];
    for (var i = 0; i < count; i++) {
        data.push(getRandomColor());
    }
    return data;
}

最后设置颜色；

var data = {
    labels: jsonData.employees, // your labels
    datasets: [{
        data: jsonData.approvedRatios, // your data
        backgroundColor: getRandomColorEachEmployee(jsonData.employees.length)
    }]
};

Answer 9

这是一种使用颜色散列生成一致随机颜色的方法

const colorHash = new ColorHash()

const datasets = [{
  label: 'Balance',
  data: _.values(balances),
  backgroundColor: _.keys(balances).map(name => colorHash.hex(name))
}]

Answer 10

这是我的处理方式：我推送了一个数组“颜色”，条目数与数据数相同。 为此，我在脚本末尾添加了一个函数“getRandomColor”。 希望能帮助到你...

for (var i in arr) {
    customers.push(arr[i].customer);
    nb_cases.push(arr[i].nb_cases);
    colors.push(getRandomColor());
}

window.onload = function() {
    var config = {
        type: 'pie',
        data: {
            labels: customers,
            datasets: [{
                label: "Nomber of cases by customers",
                data: nb_cases,
                fill: true,
                backgroundColor: colors 
            }]
        },
        options: {
            responsive: true,
            title: {
                display: true,
                text: "Cases by customers"
            },
        }
    };

    var ctx = document.getElementById("canvas").getContext("2d");
    window.myLine = new Chart(ctx, config);
};

function getRandomColor() {
    var letters = '0123456789ABCDEF'.split('');
    var color = '#';
    for (var i = 0; i < 6; i++) {
        color += letters[Math.floor(Math.random() * 16)];
    }
    return color;
}

Answer 11

如果您无法使用 NewChart.js，则只需更改使用数组设置颜色的方式即可。 在 Chart.js 中找到辅助迭代：

替换这一行：

fillColor : dataset.fillColor,

对于这个：

fillColor : dataset.fillColor[index],

结果代码：

//Iterate through each of the datasets, and build this into a property of the chart
  helpers.each(data.datasets,function(dataset,datasetIndex){

    var datasetObject = {
      label : dataset.label || null,
      fillColor : dataset.fillColor,
      strokeColor : dataset.strokeColor,
      bars : []
    };

    this.datasets.push(datasetObject);

    helpers.each(dataset.data,function(dataPoint,index){
      //Add a new point for each piece of data, passing any required data to draw.
      datasetObject.bars.push(new this.BarClass({
        value : dataPoint,
        label : data.labels[index],
        datasetLabel: dataset.label,
        strokeColor : dataset.strokeColor,
        //Replace this -> fillColor : dataset.fillColor,
        // Whith the following:
        fillColor : dataset.fillColor[index],
        highlightFill : dataset.highlightFill || dataset.fillColor,
        highlightStroke : dataset.highlightStroke || dataset.strokeColor
      }));
    },this);

  },this);

在你的 js 中：

datasets: [
                {
                  label: "My First dataset",
                  fillColor: ["rgba(205,64,64,0.5)", "rgba(220,220,220,0.5)", "rgba(24,178,235,0.5)", "rgba(220,220,220,0.5)"],
                  strokeColor: "rgba(220,220,220,0.8)",
                  highlightFill: "rgba(220,220,220,0.75)",
                  highlightStroke: "rgba(220,220,220,1)",
                  data: [2000, 1500, 1750, 50]
                }
              ]

Answer 12

试试这个 ：

  function getChartJs() {
        **var dynamicColors = function () {
            var r = Math.floor(Math.random() * 255);
            var g = Math.floor(Math.random() * 255);
            var b = Math.floor(Math.random() * 255);
            return "rgb(" + r + "," + g + "," + b + ")";
        }**

        $.ajax({
            type: "POST",
            url: "ADMIN_DEFAULT.aspx/GetChartByJenisKerusakan",
            data: "{}",
            contentType: "application/json; charset=utf-8",
            dataType: "json",
            success: function (r) {
                var labels = r.d[0];
                var series1 = r.d[1];
                var data = {
                    labels: r.d[0],
                    datasets: [
                        {
                            label: "My First dataset",
                            data: series1,
                            strokeColor: "#77a8a8",
                            pointColor: "#eca1a6"
                        }
                    ]
                };

                var ctx = $("#bar_chart").get(0).getContext('2d');
                ctx.canvas.height = 300;
                ctx.canvas.width = 500;
                var lineChart = new Chart(ctx).Bar(data, {
                    bezierCurve: false,
                    title:
                      {
                          display: true,
                          text: "ProductWise Sales Count"
                      },
                    responsive: true,
                    maintainAspectRatio: true
                });

                $.each(r.d, function (key, value) {
                    **lineChart.datasets[0].bars[key].fillColor = dynamicColors();
                    lineChart.datasets[0].bars[key].fillColor = dynamicColors();**
                    lineChart.update();
                });
            },
            failure: function (r) {
                alert(r.d);
            },
            error: function (r) {
                alert(r.d);
            }
        });
    }

Answer 13

这在当前版本2.7.1对我2.7.1 ：

function colorizePercentageChart(myObjBar) {

var bars = myObjBar.data.datasets[0].data;
console.log(myObjBar.data.datasets[0]);
for (i = 0; i < bars.length; i++) {

    var color = "green";

    if(parseFloat(bars[i])  < 95){
        color = "yellow";
    }
    if(parseFloat(bars[i])  < 50){
         color = "red";
    }

    console.log(color);
    myObjBar.data.datasets[0].backgroundColor[i] = color;

}
myObjBar.update(); 

}

Answer 14

采取另一个答案，如果您想获得每个条形随机颜色的列表，这是一个快速解决方案：

function getRandomColor(n) {
    var letters = '0123456789ABCDEF'.split('');
    var color = '#';
    var colors = [];
    for(var j = 0; j < n; j++){
        for (var i = 0; i < 6; i++ ) {
            color += letters[Math.floor(Math.random() * 16)];
        }
        colors.push(color);
        color = '#';
    }
    return colors;
}

现在您可以在数据的 backgroundColor 字段中使用此函数：

data: {
        labels: count[0],
        datasets: [{
            label: 'Registros en BDs',
            data: count[1],
            backgroundColor: getRandomColor(count[1].length)
        }]
}

Answer 15

我最近刚遇到这个问题，这是我的解决方案

var labels = ["001", "002", "003", "004", "005", "006", "007"];
var data = [20, 59, 80, 81, 56, 55, 40];
for (var i = 0, len = labels.length; i < len; i++) {
   background_colors.push(getRandomColor());// I use @Benjamin method here
}

var barChartData = {
  labels: labels,
  datasets: [{
    label: "My First dataset",
    fillColor: "rgba(220,220,220,0.5)", 
    strokeColor: "rgba(220,220,220,0.8)", 
    highlightFill: "rgba(220,220,220,0.75)",
    highlightStroke: "rgba(220,220,220,1)",
    backgroundColor: background_colors,
    data: data
  }]
};

Answer 16

基于以下拉取请求的代码：

datapoint.color = 'hsl(' + (360 * index / data.length) + ', 100%, 50%)';

Answer 17

如果你知道你想要哪种颜色，你可以在数组中指定颜色属性，如下所示：

    backgroundColor: [
    'rgba(75, 192, 192, 1)',
    ...
    ],
    borderColor: [
    'rgba(75, 192, 192, 1)',
    ...
    ],

Answer 18

在 dataPoints 中为每个条形传递一个颜色参数，如下所示：

{y: your value, label: your value, color: your color code}

Answer 19

我所做的是创建一个随机颜色生成器，正如这里的许多人所建议的

function dynamicColors() {
        var r = Math.floor(Math.random() * 255);
        var g = Math.floor(Math.random() * 255);
        var b = Math.floor(Math.random() * 255);
        return "rgba(" + r + "," + g + "," + b + ", 0.5)";
    }

然后编码这个

var chartContext = document.getElementById('line-chart');
    let lineChart = new Chart(chartContext, {
        type: 'bar',
        data : {
            labels: <?php echo json_encode($names); ?>,
            datasets: [{
                data : <?php echo json_encode($salaries); ?>,
                borderWidth: 1,
                backgroundColor: dynamicColors,
            }]
        }
        ,
        options: {
            scales: {
                yAxes: [{
                    ticks: {
                        beginAtZero: true
                    }
                }]
            },
            responsive: true,
            maintainAspectRatio: false,
        }
    });

注意函数调用处没有括号这使得代码每次都调用函数，而不是创建一个数组这也防止代码对所有条形使用相同的颜色

Answer 20

您可以使用livegap 图表轻松生成
从栏菜单中选择多色

_{（来源： livegap.com ）}

** 使用的图表库是chartnew.js修改版的chart.js 库
使用 chartnew.js 代码将是这样的

var barChartData = {
        labels: ["001", "002", "003", "004", "005", "006", "007"],
        datasets: [
            {
                label: "My First dataset",
                fillColor: ["rgba(0,10,220,0.5)","rgba(220,0,10,0.5)","rgba(220,0,0,0.5)","rgba(120,250,120,0.5)" ],
                strokeColor: "rgba(220,220,220,0.8)", 
                highlightFill: "rgba(220,220,220,0.75)",
                highlightStroke: "rgba(220,220,220,1)",
                data: [20, 59, 80, 81, 56, 55, 40]
            }
        ]
    };