我在我正在进行的项目中使用ChartJS，并且我需要为条形图中的每个条形图使用不同的颜色。
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]
}]
};
有没有办法以不同方式绘制每个栏？
解决方案：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();
}
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);
}
});
}
这在我当前的版本2.7.1中适用于我：
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();
}
我最近刚收到这个问题，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
}]
};
代码基于以下pull request：
datapoint.color = 'hsl(' + (360 * index / data.length) + ', 100%, 50%)';
回答其他问题，如果您想获得每个条形图随机颜色的列表，可以快速修复：
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)
}]
}
如果您知道所需的颜色，则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)',
...
],
您可以使用livegap charts轻松生成 从栏菜单中选择Mulicolors
http://charts.livegap.com/Gallery/images/Chart-14.png **图表库使用的是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]
}
]
};
在查看Chart.Bar.js文件后，我设法找到了解决方案。我用这个函数生成一个随机颜色：
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：”下面调用了这个函数
helpers.each(dataset.data,function(dataPoint,index){
//Add a new point for each piece of data, passing any required data to draw.
所以现在它看起来像这样：
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);
它的工作原理我每个酒吧都有不同的颜色。
从v2开始，您只需通过backgroundColor属性指定一个值数组，以对应每个条形的颜色：
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Bar Chart Dataset Properties的文档：
某些属性可以指定为数组。如果将它们设置为数组值，则第一个值应用于第一个条形，第二个值应用于第二个条形，依此类推。
如果你看一下构建在Chart.js上的库“ChartNew”，你可以通过将值作为数组传递来实现：
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]
}
]
};
您可以调用此函数为每个条形成随机颜色
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]
}
]
};
在这里，我通过制作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，传递它
datasets: [{
data: arrData,
backgroundColor: poolColors(arrData.length),
borderColor: poolColors(arrData.length),
borderWidth: 1
}]
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;
}
并为每条记录调用它;
function getRandomColorEachEmployee(count) {
var data =[];
for (var i = 0; i < count; i++) {
data.push(getRandomColor());
}
return data;
}
最后设定颜色;
var data = {
labels: jsonData.employees, // your labels
datasets: [{
data: jsonData.approvedRatios, // your data
backgroundColor: getRandomColorEachEmployee(jsonData.employees.length)
}]
};
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。在Chart.js中找到辅助迭代：
替换此行：
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：
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]
}
]
这是我如何处理：我推了一个数组“颜色”，条目数量与数据数量相同。为此，我在脚本的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;
}