Reputation: 861
Im creating a Pie chart using chartjs library, and Im wondering how I could represent the values the will be need to render the chart dynamically,
In chartjs.org tutorial the array of data is represented like this
var data = [
{
value: 300,
color:"#F7464A",
highlight: "#FF5A5E",
labelColor : 'white',
labelFontSize : '16'
},
{
value: 100,
color: "#46BFBD",
highlight: "#5AD3D1",
labelColor : 'white',
labelFontSize : '16'
},
{
value: 100,
color: "#FDB45C",
highlight: "#FFC870",
labelColor : 'white',
labelFontSize : '16'
}
]
and data will be pass as an argument to render the chart
new Chart(ctx).Pie(data);
this then renders a chart with 3 partitions:
But say I want to render X partitions, how can i make an array of data?
would I be able to do in a loop and append it to data?
Code so far:
function drawPie(ctx){
var newopts = {
inGraphDataShow: true,
inGraphDataRadiusPosition: 2,
inGraphDataFontColor: 'white',
}
//=========
// this should be dynamic (data will come the parameter)
//==========
var data = [
{
value: 300,
color:"#F7464A",
highlight: "#FF5A5E",
labelColor : 'white',
labelFontSize : '16'
},
{
value: 100,
color: "#46BFBD",
highlight: "#5AD3D1",
labelColor : 'white',
labelFontSize : '16'
},
{
value: 100,
color: "#FDB45C",
highlight: "#FFC870",
labelColor : 'white',
labelFontSize : '16'
}
]
new Chart(ctx).Pie(data, newopts);
}
Upvotes: 0
Views: 7293
Reputation: 41075
You just need to generate the data structure in the way Chart.js expects for a pie chart and if you don't know the maximum number of element generate the colors (if you know the maximum number of elements, you could just pick it from a color array). For instance
var dynamicData = [
{ label: "One", value: 23 },
{ label: "Two", value: 33 },
{ label: "Three", value: 43 },
{ label: "Four", value: 53 },
]
dynamicData.forEach(function (e, i) {
e.color = "hsl(" + (i / dynamicData.length * 360) + ", 50%, 50%)";
e.highlight = "hsl(" + (i / dynamicData.length * 360) + ", 50%, 70%)";
// + any other code you need to make your element into a chart.js pie element
})
var ctx = document.getElementById("myChart").getContext("2d");
var myPieChart = new Chart(ctx).Pie(dynamicData);
Fiddle - http://jsfiddle.net/k4ztyqzc/
Upvotes: 1