I am using Chart.js for drawing pie chart in my php page.I found tooltip as showing each slice values.
But I wish to display those values like below image. 
I do not know how to do this with chart.js.
Please help me.
My Javascript code:
function drawPie(canvasId,data,legend){
var ctx = $("#pie-canvas-" + canvasId).get(0).getContext("2d");
var piedata = [];
$.each(data,function(i,val){
piedata.push({value:val.count,color:val.color,label:val.status});
});
var options =
{
tooltipTemplate: "<%= Math.round(circumference / 6.283 * 100) %>%",
}
var pie = new Chart(ctx).Pie(piedata,options);
if(legend)document.getElementById("legend").innerHTML = pie.generateLegend();
}
php code:
printf('<table><tr>');
echo '<td style="text-align: right;"><canvas id="pie-canvas-'
. $canvasId
. '" width="256" height="256" ></canvas></td><td style="text-align: left;width:360px;height:auto" id="legend" class="chart-legend"></td></tr></table>';
echo '<script type="text/javascript">drawPie('
. $canvasId
. ', '
. $data3
.', '
. $legend
. ');</script>';
This question is related to
javascript
php
jquery
charts
The answer is
Easiest way to do this with Chartjs. Just add below line in options:
pieceLabel: {
fontColor: '#000'
}
Best of luck
I found an excellent Chart.js plugin that does exactly what you want:
https://github.com/emn178/Chart.PieceLabel.js
For Chart.js 2.0 and up, the Chart object data has changed. For those who are using Chart.js 2.0+, below is an example of using HTML5 Canvas fillText() method to display data value inside of the pie slice. The code works for doughnut chart, too, with the only difference being type: 'pie' versus type: 'doughnut' when creating the chart.
Script:
Javascript
var data = {
datasets: [{
data: [
11,
16,
7,
3,
14
],
backgroundColor: [
"#FF6384",
"#4BC0C0",
"#FFCE56",
"#E7E9ED",
"#36A2EB"
],
label: 'My dataset' // for legend
}],
labels: [
"Red",
"Green",
"Yellow",
"Grey",
"Blue"
]
};
var pieOptions = {
events: false,
animation: {
duration: 500,
easing: "easeOutQuart",
onComplete: function () {
var ctx = this.chart.ctx;
ctx.font = Chart.helpers.fontString(Chart.defaults.global.defaultFontFamily, 'normal', Chart.defaults.global.defaultFontFamily);
ctx.textAlign = 'center';
ctx.textBaseline = 'bottom';
this.data.datasets.forEach(function (dataset) {
for (var i = 0; i < dataset.data.length; i++) {
var model = dataset._meta[Object.keys(dataset._meta)[0]].data[i]._model,
total = dataset._meta[Object.keys(dataset._meta)[0]].total,
mid_radius = model.innerRadius + (model.outerRadius - model.innerRadius)/2,
start_angle = model.startAngle,
end_angle = model.endAngle,
mid_angle = start_angle + (end_angle - start_angle)/2;
var x = mid_radius * Math.cos(mid_angle);
var y = mid_radius * Math.sin(mid_angle);
ctx.fillStyle = '#fff';
if (i == 3){ // Darker text color for lighter background
ctx.fillStyle = '#444';
}
var percent = String(Math.round(dataset.data[i]/total*100)) + "%";
//Don't Display If Legend is hide or value is 0
if(dataset.data[i] != 0 && dataset._meta[0].data[i].hidden != true) {
ctx.fillText(dataset.data[i], model.x + x, model.y + y);
// Display percent in another line, line break doesn't work for fillText
ctx.fillText(percent, model.x + x, model.y + y + 15);
}
}
});
}
}
};
var pieChartCanvas = $("#pieChart");
var pieChart = new Chart(pieChartCanvas, {
type: 'pie', // or doughnut
data: data,
options: pieOptions
});
HTML
<canvas id="pieChart" width=200 height=200></canvas>
@Hung Tran's answer works perfect. As an improvement, I would suggest not showing values that are 0. Say you have 5 elements and 2 of them are 0 and rest of them have values, the solution above will show 0 and 0%. It is better to filter that out with a not equal to 0 check!
var val = dataset.data[i]; var percent = String(Math.round(val/total*100)) + "%"; if(val != 0) { ctx.fillText(dataset.data[i], model.x + x, model.y + y); // Display percent in another line, line break doesn't work for fillText ctx.fillText(percent, model.x + x, model.y + y + 15); }
Updated code below:
var data = {
datasets: [{
data: [
11,
16,
7,
3,
14
],
backgroundColor: [
"#FF6384",
"#4BC0C0",
"#FFCE56",
"#E7E9ED",
"#36A2EB"
],
label: 'My dataset' // for legend
}],
labels: [
"Red",
"Green",
"Yellow",
"Grey",
"Blue"
]
};
var pieOptions = {
events: false,
animation: {
duration: 500,
easing: "easeOutQuart",
onComplete: function () {
var ctx = this.chart.ctx;
ctx.font = Chart.helpers.fontString(Chart.defaults.global.defaultFontFamily, 'normal', Chart.defaults.global.defaultFontFamily);
ctx.textAlign = 'center';
ctx.textBaseline = 'bottom';
this.data.datasets.forEach(function (dataset) {
for (var i = 0; i < dataset.data.length; i++) {
var model = dataset._meta[Object.keys(dataset._meta)[0]].data[i]._model,
total = dataset._meta[Object.keys(dataset._meta)[0]].total,
mid_radius = model.innerRadius + (model.outerRadius - model.innerRadius)/2,
start_angle = model.startAngle,
end_angle = model.endAngle,
mid_angle = start_angle + (end_angle - start_angle)/2;
var x = mid_radius * Math.cos(mid_angle);
var y = mid_radius * Math.sin(mid_angle);
ctx.fillStyle = '#fff';
if (i == 3){ // Darker text color for lighter background
ctx.fillStyle = '#444';
}
var val = dataset.data[i];
var percent = String(Math.round(val/total*100)) + "%";
if(val != 0) {
ctx.fillText(dataset.data[i], model.x + x, model.y + y);
// Display percent in another line, line break doesn't work for fillText
ctx.fillText(percent, model.x + x, model.y + y + 15);
}
}
});
}
}
};
var pieChartCanvas = $("#pieChart");
var pieChart = new Chart(pieChartCanvas, {
type: 'pie', // or doughnut
data: data,
options: pieOptions
});
Source: Stackoverflow.com