Develop Reference

How to display percentages in pie chart (ChartJS)

I am in the development of some graphs with the help of the Chart.js library and among them I am making use of a pie chart or better known with Pie Chart and I am looking for some way to add their respective percentages on the graph as well as the image that I add as an example at the end of the snippet.
Currently the graph is shown but I cannot show their respective percentages.
const pieData = [
{
value: 72,
color: "#4EADEB",
// highlight: "#FF5A5E",
label: "Avance"
},
{
value: 28,
color: "#3F86CB",
//highlight: "#5AD3D1",
label: "Pendiente"
}
];
const pieOptions = {
//Boolean - Whether we should show a stroke on each segment
segmentShowStroke: true,
//String - The colour of each segment stroke
segmentStrokeColor: "#fff",
//Number - The width of each segment stroke
segmentStrokeWidth: 2,
//Number - The percentage of the chart that we cut out of the middle
percentageInnerCutout: 0, // This is 0 for Pie charts
//Number - Amount of animation steps
animationSteps: 100,
//String - Animation easing effect
animationEasing: "easeOutBounce",
//Boolean - Whether we animate the rotation of the Doughnut
animateRotate: true,
//Boolean - Whether we animate scaling the Doughnut from the centre
animateScale: false,
//String - A legend template
legendTemplate:
'<ul class="<%=name.toLowerCase()%>-legend"><% for (var i=0; i<segments.length; i++){%><li><span style="background-color:<%=segments[i].fillColor%>"></span><%if(segments[i].label){%><%=segments[i].label%><%}%></li><%}%></ul>'
};
const pieCtx = document.getElementById("myPieGraph").getContext("2d");
const myPieChart = new Chart(pieCtx).Pie(pieData, pieOptions);
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/1.1.1/Chart.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/1.1.1/Chart.js"></script>
<canvas id="myPieGraph" height="120" width="240"></canvas>
Example Image:
Note:
Before the question closes for possible duplication, in this question it seeks to add the percentages but the version they use here is 0.4.0, the version that I am using of ChartJS is 1.1.1.
The use of its properties are different.

Chart.js line chart display decimal values on Y axis

I'm dealing with an ASP.NET MVC5 application which makes use of Chart.js library to display a line chart.
I am not able to display decimal values on the Y axis.
The values appear as integer on the chart. Any idea why?
float[] currentTemperatureArray = ViewBag.valuesArray;
string[] labelsArray = ViewBag.labelsArray;
<script>
var chartLabels = [];
var chartValuesCT = [];
#{
for (int i = 0; i < labelsArray.Length; i++)
{
#:chartLabels[#i] = "#labelsArray[i]";
}
}
#{
for (int i = 0; i < currentTemperatureArray.Length; i++)
{
#:chartValuesCT[#i] = #currentTemperatureArray[i];
}
var lineChartData =
{
labels: chartLabels,
datasets : [
{
label: "Current Temperature",
format: '{value:.5f}',
fillColor : "rgba(220,220,220,0.2)",
strokeColor : "rgba(220,220,220,1)",
pointColor : "rgba(220,220,220,1)",
pointStrokeColor : "#fff",
pointHighlightFill : "#fff",
pointHighlightStroke : "rgba(220,220,220,1)",
data: chartValuesCT
}]}
window.onload = function(){
var ctx = document.getElementById("canvas").getContext("2d");
ctx.canvas.height = window.innerHeight;
ctx.canvas.width = window.innerWidth;
window.myLine = new Chart(ctx).Line(lineChartData, {
scaleOverride : true,
scaleSteps : 1,
scaleStepWidth : 20,
scaleStartValue : -20,
responsive: true
});
}
</script>

The problem lies in how the decimal numbers are formatted. Apparently there is an error by converting the number from .NET to javascript. The comma versus dot standard seems to be important here.

How to dynamically change point location with line in Chart.js?

I am using the line graph in Chart.js v1 stable, and I want to dynamically change the point location along with the ling thats attached to it, so like if I slide the point up using javascript, then the point attached to it moves too. Does anyone know how to do it?
Thanks
$(document).ready(function() {
var data = {
labels: ["Dec", "Jan", "Feb", "March", "April", "May", "June"],
datasets: [
{
label: "My Second dataset",
fillColor: "rgba(151,187,205,0.2)",
strokeColor: "#ed1b2e",
pointColor: "red",
pointStrokeColor: "#fff",
pointHighlightFill: "#fff",
pointHighlightStroke: "rgba(151,187,205,1)",
data: [-28, -48, -40, -19, -86, -27, -90]
}
]
};
// Get the context of the canvas element we want to select
var ctx = document.getElementById("myChart").getContext("2d");
var myLineChart = new Chart(ctx).Line(data, {
bezierCurve: false
});
setTimeout(function() {
var len = myLineChart.datasets[0].points.length;
myLineChart.datasets[0].points[len-1].fillColor = "blue";
myLineChart.datasets[0].points[len-1].y = 250; // <---- doesn't work, it moves but then slides back to initial location
myLineChart.update();
}, 5000);
var g = myLineChart.datasets[0];
Chart.defaults.global = {
// Boolean - Whether to animate the chart
animation: true,
// Number - Number of animation steps
animationSteps: 60,
// String - Animation easing effect
// Possible effects are:
// [easeInOutQuart, linear, easeOutBounce, easeInBack, easeInOutQuad,
// easeOutQuart, easeOutQuad, easeInOutBounce, easeOutSine, easeInOutCubic,
// easeInExpo, easeInOutBack, easeInCirc, easeInOutElastic, easeOutBack,
// easeInQuad, easeInOutExpo, easeInQuart, easeOutQuint, easeInOutCirc,
// easeInSine, easeOutExpo, easeOutCirc, easeOutCubic, easeInQuint,
// easeInElastic, easeInOutSine, easeInOutQuint, easeInBounce,
// easeOutElastic, easeInCubic]
animationEasing: "easeOutQuart",
// Boolean - If we should show the scale at all
showScale: true,
// Boolean - If we want to override with a hard coded scale
scaleOverride: false,
// ** Required if scaleOverride is true **
// Number - The number of steps in a hard coded scale
scaleSteps: null,
// Number - The value jump in the hard coded scale
scaleStepWidth: null,
// Number - The scale starting value
scaleStartValue: null,
// String - Colour of the scale line
scaleLineColor: "rgba(0,0,0,.1)",
// Number - Pixel width of the scale line
scaleLineWidth: 1,
// Boolean - Whether to show labels on the scale
scaleShowLabels: true,
// Interpolated JS string - can access value
scaleLabel: "<%=value%>",
// Boolean - Whether the scale should stick to integers, not floats even if drawing space is there
scaleIntegersOnly: true,
// Boolean - Whether the scale should start at zero, or an order of magnitude down from the lowest value
scaleBeginAtZero: false,
// String - Scale label font declaration for the scale label
scaleFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
// Number - Scale label font size in pixels
scaleFontSize: 12,
// String - Scale label font weight style
scaleFontStyle: "normal",
// String - Scale label font colour
scaleFontColor: "#666",
// Boolean - whether or not the chart should be responsive and resize when the browser does.
responsive: true,
// Boolean - whether to maintain the starting aspect ratio or not when responsive, if set to false, will take up entire container
maintainAspectRatio: true,
// Boolean - Determines whether to draw tooltips on the canvas or not
showTooltips: true,
// Function - Determines whether to execute the customTooltips function instead of drawing the built in tooltips (See [Advanced - External Tooltips](#advanced-usage-custom-tooltips))
customTooltips: false,
// Array - Array of string names to attach tooltip events
tooltipEvents: ["mousemove", "touchstart", "touchmove"],
// String - Tooltip background colour
tooltipFillColor: "rgba(0,0,0,0.8)",
// String - Tooltip label font declaration for the scale label
tooltipFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
// Number - Tooltip label font size in pixels
tooltipFontSize: 14,
// String - Tooltip font weight style
tooltipFontStyle: "normal",
// String - Tooltip label font colour
tooltipFontColor: "#fff",
// String - Tooltip title font declaration for the scale label
tooltipTitleFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
// Number - Tooltip title font size in pixels
tooltipTitleFontSize: 14,
// String - Tooltip title font weight style
tooltipTitleFontStyle: "bold",
// String - Tooltip title font colour
tooltipTitleFontColor: "#fff",
// Number - pixel width of padding around tooltip text
tooltipYPadding: 6,
// Number - pixel width of padding around tooltip text
tooltipXPadding: 6,
// Number - Size of the caret on the tooltip
tooltipCaretSize: 8,
// Number - Pixel radius of the tooltip border
tooltipCornerRadius: 6,
// Number - Pixel offset from point x to tooltip edge
tooltipXOffset: 10,
// String - Template string for single tooltips
tooltipTemplate: "<%if (label){%><%=label%>: <%}%><%= value %>",
// String - Template string for multiple tooltips
multiTooltipTemplate: "<%= value %>",
// Function - Will fire on animation progression.
onAnimationProgress: function(){},
// Function - Will fire on animation completion.
onAnimationComplete: function(){}
}
});

Use .value instead of .y i.e.
myLineChart.datasets[0].points[len - 1].value = 250

Chart.js not appearing in tabs

I know there are examples but they didn't work for me.
I'm using joomla and trying to embed a line chart in a tab, works on the first tab but not the 2nd, any ideas would be appreciated.
here's the script and I don't really know javascript that well.
Many Thanks:
<canvas id="myChart-a" height="320" width="1200"></canvas>
<script src="templates/jux_forlio/js/chart.js"></script>
<script type="text/javascript">
var lineChartData = {
labels : ["January","February","March","April","May","June","July","August","September","October","November","December"],
datasets : [
{
fillColor : "rgba(162,29,9,0.5)",
strokeColor : "rgba(162,29,9,1)",
pointColor : "rgba(162,29,9,1)",
pointStrokeColor : "#fff",
data : [30,29,26,23,19,16,15,17,19,22,25,28]
},
{
fillColor : "rgba(151,187,205,0.5)",
strokeColor : "rgba(151,187,205,1)",
pointColor : "rgba(151,187,205,1)",
pointStrokeColor : "#fff",
data : [20,19,17,14,10,8,7,9,10,13,16,18]
}
]
},
options = {
//Boolean - If we show the scale above the chart data
scaleOverlay : true,
scaleShowValues : true,
//Boolean - If we want to override with a hard coded scale
scaleOverride : false,
//** Required if scaleOverride is true **
//Number - The number of steps in a hard coded scale
scaleSteps : null,
//Number - The value jump in the hard coded scale
scaleStepWidth : null,
//Number - The scale starting value
scaleStartValue : null,
//String - Colour of the scale line
scaleLineColor : "rgba(f,f,f,.1)",
//Number - Pixel width of the scale line
scaleLineWidth : 1,
//Boolean - Whether to show labels on the scale
scaleShowLabels : true,
//Interpolated JS string - can access value
scaleLabel : "<%=value%>",
//String - Scale label font declaration for the scale label
scaleFontFamily : "'Arial'",
//Number - Scale label font size in pixels
scaleFontSize : 20,
//String - Scale label font weight style
scaleFontStyle : "normal",
//String - Scale label font colour
scaleFontColor : "#fff",
///Boolean - Whether grid lines are shown across the chart
scaleShowGridLines : true,
//String - Colour of the grid lines
scaleGridLineColor : "rgba(0,0,0,.05)",
//Number - Width of the grid lines
scaleGridLineWidth : 1,
//Boolean - Whether the line is curved between points
bezierCurve : true,
//Boolean - Whether to show a dot for each point
pointDot : true,
//Number - Radius of each point dot in pixels
pointDotRadius : 3,
//Number - Pixel width of point dot stroke
pointDotStrokeWidth : 1,
//Boolean - Whether to show a stroke for datasets
datasetStroke : true,
//Number - Pixel width of dataset stroke
datasetStrokeWidth : 2,
//Boolean - Whether to fill the dataset with a colour
datasetFill : true,
//Boolean - Whether to animate the chart
animation : true,
//Number - Number of animation steps
animationSteps : 60,
//String - Animation easing effect
animationEasing : "easeOutQuart",
//Function - Fires when the animation is complete
onAnimationComplete : null,
// Boolean - whether or not the chart should be responsive and resize when the browser does.
responsive: true,
// Boolean - whether to maintain the starting aspect ratio or not when responsive, if set to false, will take up entire container
maintainAspectRatio: true
}
//Get the context of the canvas element we want to select
var ctx = document.getElementById("myChart-a").getContext("2d");
var myNewChart = new Chart(ctx).Line(lineChartData, options);
</script>

Assuming the tabs HTML includes "li" tags - like this -
<li class="" onclick="javascript:drawChart();"> </li>
Note: on clicking a javascript function is called. Add onclick attribute for the tab-li where you want to show the chart.
Then the remaining code remains the same except the lines given below moved inside the JS function .
//Get the context of the canvas element we want to select
var ctx = document.getElementById("myChart-a").getContext("2d");
var myNewChart = new Chart(ctx).Line(lineChartData, options);
This should do the trick!
<script>
var lineChartData = {
labels : ["January","February","March","April","May","June","July","August","September","October","November","December"],
datasets : [
{
fillColor : "rgba(162,29,9,0.5)",
strokeColor : "rgba(162,29,9,1)",
pointColor : "rgba(162,29,9,1)",
pointStrokeColor : "#fff",
data : [30,29,26,23,19,16,15,17,19,22,25,28]
},
{
fillColor : "rgba(151,187,205,0.5)",
strokeColor : "rgba(151,187,205,1)",
pointColor : "rgba(151,187,205,1)",
pointStrokeColor : "#fff",
data : [20,19,17,14,10,8,7,9,10,13,16,18]
}
]
},
options = {
//Boolean - If we show the scale above the chart data
scaleOverlay : true,
scaleShowValues : true,
//Boolean - If we want to override with a hard coded scale
scaleOverride : false,
//** Required if scaleOverride is true **
//Number - The number of steps in a hard coded scale
scaleSteps : null,
//Number - The value jump in the hard coded scale
scaleStepWidth : null,
//Number - The scale starting value
scaleStartValue : null,
//String - Colour of the scale line
scaleLineColor : "rgba(f,f,f,.1)",
//Number - Pixel width of the scale line
scaleLineWidth : 1,
//Boolean - Whether to show labels on the scale
scaleShowLabels : true,
//Interpolated JS string - can access value
scaleLabel : "<%=value%>",
//String - Scale label font declaration for the scale label
scaleFontFamily : "'Arial'",
//Number - Scale label font size in pixels
scaleFontSize : 20,
//String - Scale label font weight style
scaleFontStyle : "normal",
//String - Scale label font colour
scaleFontColor : "#fff",
///Boolean - Whether grid lines are shown across the chart
scaleShowGridLines : true,
//String - Colour of the grid lines
scaleGridLineColor : "rgba(0,0,0,.05)",
//Number - Width of the grid lines
scaleGridLineWidth : 1,
//Boolean - Whether the line is curved between points
bezierCurve : true,
//Boolean - Whether to show a dot for each point
pointDot : true,
//Number - Radius of each point dot in pixels
pointDotRadius : 3,
//Number - Pixel width of point dot stroke
pointDotStrokeWidth : 1,
//Boolean - Whether to show a stroke for datasets
datasetStroke : true,
//Number - Pixel width of dataset stroke
datasetStrokeWidth : 2,
//Boolean - Whether to fill the dataset with a colour
datasetFill : true,
//Boolean - Whether to animate the chart
animation : true,
//Number - Number of animation steps
animationSteps : 60,
//String - Animation easing effect
animationEasing : "easeOutQuart",
//Function - Fires when the animation is complete
onAnimationComplete : null,
// Boolean - whether or not the chart should be responsive and resize when the browser does.
responsive: true,
// Boolean - whether to maintain the starting aspect ratio or not when responsive, if set to false, will take up entire container
maintainAspectRatio: true
}
function drawChart()
{
//Get the context of the canvas element we want to select
var ctx = document.getElementById("myChart-a").getContext("2d");
var myNewChart = new Chart(ctx).Line(lineChartData, options);
}
</script>
I hope this helps!

Chart JS custom tooltip option?

I am trying to build chart using Chart.Js. This chart.js has default option for tooltip, I want to make customized tooltip option. Is there a way to make it possible?
Here is my code
var chart = null;
barChart: function (data1, data2, data3, label) {
var data = {
labels: label,
datasets: [
{
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: data1
},
{
fillColor: "rgba(151,187,205,0.5)",
strokeColor: "rgba(151,187,205,0.8)",
highlightFill: "rgba(151,187,205,0.75)",
highlightStroke: "rgba(151,187,205,1)",
data: data2
},
{
fillColor: "rgba(0,255,0,0.3)",
strokeColor: "rgba(220,220,220,0.8)",
highlightFill: "rgba(220,220,220,0.75)",
highlightStroke: "rgba(0,255,0,0.3)",
data: data3
},
]
}
var cht = document.getElementById('exampleCanvas');
var ctx = cht.getContext('2d');
if (chart)
chart.destroy();
chart = new Chart(ctx).Bar(data);
}

Try this:
You can make changes globally using this code:
Chart.defaults.global = {
// Boolean - Determines whether to draw tooltips on the canvas or not
showTooltips: true,
// Array - Array of string names to attach tooltip events
tooltipEvents: ["mousemove", "touchstart", "touchmove"],
// String - Tooltip background colour
tooltipFillColor: "rgba(0,0,0,0.8)",
// String - Tooltip label font declaration for the scale label
tooltipFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
// Number - Tooltip label font size in pixels
tooltipFontSize: 14,
// String - Tooltip font weight style
tooltipFontStyle: "normal",
// String - Tooltip label font colour
tooltipFontColor: "#fff",
// String - Tooltip title font declaration for the scale label
tooltipTitleFontFamily: "'Helvetica Neue', 'Helvetica', 'Arial', sans-serif",
// Number - Tooltip title font size in pixels
tooltipTitleFontSize: 14,
// String - Tooltip title font weight style
tooltipTitleFontStyle: "bold",
// String - Tooltip title font colour
tooltipTitleFontColor: "#fff",
// Number - pixel width of padding around tooltip text
tooltipYPadding: 6,
// Number - pixel width of padding around tooltip text
tooltipXPadding: 6,
// Number - Size of the caret on the tooltip
tooltipCaretSize: 8,
// Number - Pixel radius of the tooltip border
tooltipCornerRadius: 6,
// Number - Pixel offset from point x to tooltip edge
tooltipXOffset: 10,
// String - Template string for single tooltips
tooltipTemplate: "<%if (label){%><%=label%>: <%}%><%= value %>",
// String - Template string for single tooltips
multiTooltipTemplate: "<%= value %>",
// Function - Will fire on animation progression.
onAnimationProgress: function(){},
// Function - Will fire on animation completion.
onAnimationComplete: function(){}
}
Use this Link for reference

The new version of chart.js, version 2, is found here:
https://github.com/nnnick/Chart.js/releases
Version 2 adds tooltip callbacks:
Every tooltip callback (beforeTitle, title, afterTitle, etc..) accepts a string or an array. If an array is used, it will produce multiple lines. Tooltips now come with a lot more options for visual customization as well.
However, there is a fork of chart.js called chartNew.js, found here:
https://github.com/FVANCOP/ChartNew.js/
It adds several great enhancements to the venerable chart.js, including:
tooltip functions (when download/unzip, look in the Samples folder and look at annotateFunction.html. When hover over any point, you can do anything.)
passing an array of colors to a bar chart (instead of each bar in series having the same color)
putting text on the chart wherever you want it
many etceteras.
Note that chart.js has been greatly enhanced in version 2, but the new version is not fully backwards compatible (just changing to the v2 plugin broke my existing code) whereas chartNew.js will work with old code whilst extending capabilities.

I have used this, i've found it on stackoverflow, but i try hardly to find it again
<div id="chartjs-tooltip"></div>
var chartoptions =
{
customTooltips: function ( tooltip )
{
var tooltipEl = $( "#chartjs-tooltip" );
if ( !tooltip )
{
tooltipEl.css( {
opacity: 0
} );
return;
}
tooltipEl.removeClass( 'above below' );
tooltipEl.addClass( tooltip.yAlign );
// split out the label and value and make your own tooltip here
var parts = tooltip.text.split( ":" );
var innerHtml = '<span>' + parts[0].trim() + '</span> : <span><b>' + parts[1].trim() + '</b></span>';
tooltipEl.html( innerHtml );
tooltipEl.css( {
opacity: 1,
left: tooltip.chart.canvas.offsetLeft + tooltip.x + 'px',
top: tooltip.chart.canvas.offsetTop + tooltip.y + 'px',
fontFamily: tooltip.fontFamily,
fontSize: tooltip.fontSize,
fontStyle: tooltip.fontStyle
} );
}
}
Link to where i got it: Chart.js: changing tooltip template

You can check for tooltip css - http://www.chartjs.org/docs/#chart-configuration-tooltip-configuration
tooltips:
{
bodyFontColor: "#000000", //#000000
bodyFontSize: 50,
bodyFontStyle: "bold",
bodyFontColor: '#FFFFFF',
bodyFontFamily: "'Helvetica', 'Arial', sans-serif",
footerFontSize: 50,
callbacks: {
label: function(tooltipItem, data) {
var value = data.datasets[0].data[tooltipItem.index];
if(tooltipItem.index == 0) {
return "<?php echo $data1;?>";
}
else if(tooltipItem.index == 1) {
return "<?php echo $data2;?>";
}
else if(tooltipItem.index == 2) {
return "<?php echo $data3;?>";
}
else {
return "<?php echo $data4; ?>";
}
},
},
},

It is very simple when you know where to put the option.
The answer is to add the custom option when you create the chart :
chart = new Chart(ctx).Bar(data, {"options goes here"} );
After you pass the data variable with the data info you can add custom options, so for example you want to change the size of the Title of the tooltip and you also want to put a light grey color in the title of the tooltip you would do something like that:
chart = new Chart(ctx).Bar(data, {
//Option for title font size in pixels
tooltipTitleFontSize: 14,
//Option for tooltip title color
tooltipTitleFontColor: "#eee"
});
Another way you can do is to create the set of options as a variable for organisation purposes and to be able to reuse it.
// Create a set of relevant options for you chart
var myoptions = {
scaleShowGridLines : false,
responsive : true,
scaleFontSize: 12,
pointDotRadius : 4,
scaleFontStyle: 14,
scaleLabel: "<%= ' ' + value%> %",
}
//Create the Chart
chart = new Chart(ctx).Bar(data, myoptions);
I hope it is clear now
Regards

I found this page to be helpful:
https://github.com/nnnick/Chart.js/blob/master/samples/pie-customTooltips.html
He shows where and how to define the function for your custom tooltip, as well as an example of the styling.
I had to modify the code to match my needs, but this is a great example on how to implement the custom tooltip feature.
Some things to note that threw me off at first:
1) The id in the style rules need to be modified to match your tooltip div. (this is obvious, but I didn't catch it at first)
2) tooltip.text will follow the format you set for 'tooltipTemplate' in your options, or the default tooltipTemplate set in chart.js

may be this can help you
Chart.types.Line.extend({
name: "LineAlt",
initialize: function (data) {
Chart.types.Line.prototype.initialize.apply(this, arguments);
var xLabels = this.scale.xLabels
xLabels.forEach(function (label, i) {
if (i % 2 == 1)
xLabels[i] = label.substring(1, 4);
})
}
});
var data = {
labels: ["1/jan/08", "15/fab/08", "1/mar/08", "1/apr/08", "10/apr/08", "10/may/2008", "1/jun/2008"],
datasets: [{
label: "First dataset",
fillColor: "rgba(220,220,220,0.2)",
strokeColor: "rgba(220,20,20,1)",
pointColor: "rgba(220,20,20,1)",
pointStrokeColor: "#fff",
pointHighlightFill: "#fff",
pointHighlightStroke: "rgba(220,220,220,1)",
data: [65, 59, 80, 81, 56, 55, 90]
}, {
label: "Third dataset",
fillColor: "rgba(151,187,205,0.2)",
strokeColor: "rgba(15,187,25,1)",
pointColor: "rgba(15,187,25,1)",
pointStrokeColor: "#fff",
pointHighlightFill: "#fff",
pointHighlightStroke: "rgba(151,187,205,1)",
data: [38, 55, 50, 65, 35, 67, 54]
}]
};
var ctx = document.getElementById("myChart").getContext("2d");
var myChart = new Chart(ctx).LineAlt(data);
// Chart.js replaces the base inRange function for Line points with a function that checks only the x coordinate
// we replace it with the original inRange fucntion (one that checks both x and y coordinates)
myChart.datasets.forEach(function(dataset) {
dataset.points.forEach(function(point) {
point.inRange = Chart.Point.prototype.inRange;
});
});
// Chart.js shows a multiTooltip based on the index if it detects that there are more than one datasets
// we override it to show a single tooltip for the inRange element
myChart.showTooltip = function(ChartElements, forceRedraw) {
// this clears out the existing canvas - the actual Chart.js library code is a bit more optimized with checks for whether active points have changed, etc.
this.draw();
// draw tooltip for active elements (if there is one)
Chart.helpers.each(ChartElements, function(Element) {
var tooltipPosition = Element.tooltipPosition();
new Chart.Tooltip({
x: Math.round(tooltipPosition.x),
y: Math.round(tooltipPosition.y),
xPadding: this.options.tooltipXPadding,
yPadding: this.options.tooltipYPadding,
fillColor: this.options.tooltipFillColor,
textColor: this.options.tooltipFontColor,
fontFamily: this.options.tooltipFontFamily,
fontStyle: this.options.tooltipFontStyle,
fontSize: this.options.tooltipFontSize,
caretHeight: this.options.tooltipCaretSize,
cornerRadius: this.options.tooltipCornerRadius,
text: Chart.helpers.template(this.options.tooltipTemplate, Element),
chart: this.chart,
custom: this.options.customTooltips
}).draw();
}, this);
};
http://jsfiddle.net/6cgo4opg/747/