I need to create custom legend for my donut chart using ChartJS library.
I have created donut with default legend provided by ChartJS but I need some modification.
I would like to have value above the car name. Also I don't like sticky legend I want to have it separate from donut so I can change the style for fonts, boxes (next to the text "Audi" for example)
I know there is some Legend generator but I'm not sure how to use it with VueJS - because I'm using VueJS as a framework
This is how my legend looks like now - http://imgur.com/a/NPUoi
My code:
From Vue component where I import a donut component:
<div class="col-md-6">
<div class="chart-box">
<p class="chart-title">Cars</p>
<donut-message id="chart-parent"></donut-message>
</div>
</div>
Javascript:
import { Doughnut } from 'vue-chartjs'
export default Doughnut.extend({
ready () {
Chart.defaults.global.tooltips.enabled = false;
Chart.defaults.global.legend.display = false;
this.render({
labels: ['Audi','BMW','Ford','Opel'],
datasets: [
{
label: 'Cars',
backgroundColor: ['#35d89b','#4676ea','#fba545','#e6ebfd'],
data: [40, 30, 20, 10]
}
]
},
{
responsive: true,
cutoutPercentage: 75,
legend: {
display: true,
position: "right",
fullWidth: true,
labels: {
boxWidth: 10,
fontSize: 14
}
},
animation: {
animateScale: true
}
})
}
});
I'm having the same problem trying to understand the documentation and this link might clarify the process of customize the legends:
https://codepen.io/michiel-nuovo/pen/RRaRRv
The trick is to track a callback to build your own HTML structure and return this new structure to ChartJS.
Inside the options object:
legendCallback: function(chart) {
var text = [];
text.push('<ul class="' + chart.id + '-legend">');
for (var i = 0; i < chart.data.datasets[0].data.length; i++) {
text.push('<li><span style="background-color:' +
chart.data.datasets[0].backgroundColor[i] + '">');
if (chart.data.labels[i]) {
text.push(chart.data.labels[i]);
}
text.push('</span></li>');
}
text.push('</ul>');
return text.join("");
}
Second, you need a container to insert the new html and using the method myChart.generateLegend() to get the customized html:
$("#your-legend-container").html(myChart.generateLegend());
After that, if you need, track down the events:
$("#your-legend-container").on('click', "li", function() {
myChart.data.datasets[0].data[$(this).index()] += 50;
myChart.update();
console.log('legend: ' + data.datasets[0].data[$(this).index()]);
});
$('#myChart').on('click', function(evt) {
var activePoints = myChart.getElementsAtEvent(evt);
var firstPoint = activePoints[0];
if (firstPoint !== undefined) {
console.log('canvas: ' +
data.datasets[firstPoint._datasetIndex].data[firstPoint._index]);
}
else {
myChart.data.labels.push("New");
myChart.data.datasets[0].data.push(100);
myChart.data.datasets[0].backgroundColor.push("red");
myChart.options.animation.animateRotate = false;
myChart.options.animation.animateScale = false;
myChart.update();
$("#your-legend-container").html(myChart.generateLegend());
}
}
Another solution that I found, if you don't need to change the HTMl structure inside the legend, you can just insert the same HTML in your legend container and customize it by CSS, check this another link:
http://jsfiddle.net/vrwjfg9z/
Hope it works for you.
You can extract the legend markup.
data () {
return {
legendMarkup: ''
}
},
ready () {
this.legendMarkup = this._chart.generateLegend()
}
And in your template you can output it.
<div class="legend" ref="legend" v-html="legendMarkup"></div>
this._chart is the internal chartjs instance in vue-chartjs. So you can call all chartjs methods which are not exposed by vue-chartjs api over it.
However you can also use the legend generator. The usage is the same in vue. You can pass in the options, use callbacks etc.
please check this documentation
.
Legend Configuration
The chart legend displays data about the datasets that area appearing on the chart.
Configuration options
Position of the legend. Options are:
'top'
'left'
'bottom'
'right'
Legend Item Interface
Items passed to the legend onClick function are the ones returned from labels.generateLabels. These items must implement the following interface.
{
// Label that will be displayed
text: String,
// Fill style of the legend box
fillStyle: Color,
// If true, this item represents a hidden dataset. Label will be rendered with a strike-through effect
hidden: Boolean,
// For box border. See https://developer.mozilla.org/en/docs/Web/API/CanvasRenderingContext2D/lineCap
lineCap: String,
// For box border. See https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/setLineDash
lineDash: Array[Number],
// For box border. See https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/lineDashOffset
lineDashOffset: Number,
// For box border. See https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/lineJoin
lineJoin: String,
// Width of box border
lineWidth: Number,
// Stroke style of the legend box
strokeStyle: Color
// Point style of the legend box (only used if usePointStyle is true)
pointStyle: String
}
Example
The following example will create a chart with the legend enabled and turn all of the text red in color.
var chart = new Chart(ctx, {
type: 'bar',
data: data,
options: {
legend: {
display: true,
labels: {
fontColor: 'rgb(255, 99, 132)'
}
}
}
});
Custom On Click Actions
It can be common to want to trigger different behaviour when clicking an item in the legend. This can be easily achieved using a callback in the config object.
The default legend click handler is:
function(e, legendItem) {
var index = legendItem.datasetIndex;
var ci = this.chart;
var meta = ci.getDatasetMeta(index);
// See controller.isDatasetVisible comment
meta.hidden = meta.hidden === null? !ci.data.datasets[index].hidden : null;
// We hid a dataset ... rerender the chart
ci.update();
}
Lets say we wanted instead to link the display of the first two datasets. We could change the click handler accordingly.
var defaultLegendClickHandler = Chart.defaults.global.legend.onClick;
var newLegendClickHandler = function (e, legendItem) {
var index = legendItem.datasetIndex;
if (index > 1) {
// Do the original logic
defaultLegendClickHandler(e, legendItem);
} else {
let ci = this.chart;
[ci.getDatasetMeta(0),
ci.getDatasetMeta(1)].forEach(function(meta) {
meta.hidden = meta.hidden === null? !ci.data.datasets[index].hidden : null;
});
ci.update();
}
};
var chart = new Chart(ctx, {
type: 'line',
data: data,
options: {
legend: {
}
}
});
Now when you click the legend in this chart, the visibility of the first two datasets will be linked together.
HTML Legends
Sometimes you need a very complex legend. In these cases, it makes sense to generate an HTML legend. Charts provide a generateLegend() method on their prototype that returns an HTML string for the legend.
To configure how this legend is generated, you can change the legendCallback config property.
var chart = new Chart(ctx, {
type: 'line',
data: data,
options: {
legendCallback: function(chart) {
// Return the HTML string here.
}
}
});
Related
I am using highchart-react-official, I am using it draw two charts:
1) Line chart with multiple series
2) Column Chart.
Now I want, if I hover over a point in first chart, it should display highlight point on both lines of first chart and column chart in second chart. Like a synchronized chart: http://jsfiddle.net/doc_snyder/51zdn0jz/6/
This is my code:
((H) => {
H.Pointer.prototype.reset = () => undefined;
/**
* Highlight a point by showing tooltip, setting hover state and
draw crosshair
*/
H.Point.prototype.highlight = function highlight(event) {
event = this.series.chart.pointer.normalize(event);
this.onMouseOver(); // Show the hover marker
this.series.chart.tooltip.refresh(this); // Show the tooltip
this.series.chart.xAxis[0].drawCrosshair(event, this); // Show the crosshair
};
H.syncExtremes = function syncExtremes(e) {
const thisChart = this.chart;
if (e.trigger !== 'syncExtremes') {
// Prevent feedback loop
Highcharts.each(Highcharts.charts, (chart) => {
if (chart && chart !== thisChart) {
if (chart.xAxis[0].setExtremes) {
// It is null while updating
chart.xAxis[0].setExtremes(e.min, e.max, undefined, false, {
trigger: 'syncExtremes',
});
}
}
});
}
};
})(Highcharts);
componentDidMount() {
this.changeChart();
['mousemove', 'touchmove', 'touchstart'].forEach((eventType) => {
document
.getElementById('tab__charts')
.addEventListener(eventType, (e) => {
for (let i = 0; i < Highcharts.charts.length; i += 1) {
const chart = Highcharts.charts[i];
// let secSeriesIndex = 1;
if (chart) {
// Find coordinates within the chart
const event = chart.pointer.normalize(e);
// Get the hovered point
chart.series.forEach(series => {
const point = series.searchPoint(event, true);
if (point) {
point.highlight(e);
}
});
}
}
});
});
}
Some imporant chart config:
tooltip: {
enabled: true,
useHTML: true,
shared: true,
}
xAxis: {
events: {
setExtremes: (e) => {
Highcharts.syncExtremes(e);
},
}
}
Now this code is working perfectly by synchronizing tooltip on both charts. But the issue is in first chart, it has two lines, when I hover over first line it hightlights the point with round circle, but the second line is not getting highlighted.
And the reason I found for that is in point.highlight(e); in componendDidMount
For second series, this line giving error on hover:
More specifically, point.highligh(e) is calling top function: H.Point.prototype.highlight = (), check top of the question, in that function this function call is resulting in error
this.series.chart.tooltip.refresh(this);
Note: I'll try to reproduce and create a jsfiddle or something like that, but posting this just so if anyone can help figure this out.
And I am passing Array of Object in Series data, because I need more informative tooltip on chart point:
data: [{
"x": "2018-12-23T11:00:09.311Z",
"y": 107.54,
"data": {
"Toltip Info 1": "1,884,681,725",
"Tooltip info 2": "158,039,757.99",
"price":"107.54"
}
}]
Here is demo of the issue: https://codesandbox.io/s/pk2w85jpk0
The problem is the data format, x values should be in milliseconds:
data: [
{
x: new Date("2018-12-25T09:00:06.247Z").getTime(),
y: 6609592859.48
},
...
]
Live demo: https://codesandbox.io/s/ovk25m493q
Hi i want to show/hide the legend of my linechart (chart.js) by clicking a button.
I tried this so far:
The following code changes the value of scatterChart.legend.options.display but after executing scatterChart.update() the value changes automatically to the initial value!
function showHideLegend() {
console.log(scatterChart.legend.options.display); // -> "inital-value" e.g.: true
if (scatterChart.legend.options.display == true) {
scatterChart.legend.options.display = false;
} else {
scatterChart.legend.options.display = true;
}
console.log(scatterChart.legend.options.display); // -> value successfully changed e.g.: false
scatterChart.update();
//Chart.defaults.global.legend.display = false; // <- does not have an effect
console.log(scatterChart.legend.options.display); // -> "inital-value" e.g.: true
}
function initMap() {
scatterChart = new Chart(document.getElementById("scatterChart"), {
type: 'line',
data: {
/*datasets: [
]
*/
},
showScale: false,
options: {
legend: {
position: 'right',
labels: {
fontSize: 15
}
}
}
});
HTML
<canvas id="scatterChart" style="width: 1920px; height: 1080px; background-image:url('image.jpg'); background-size: 100% 100%;"></canvas>
<div id="scatterLegend"> //howToPutLegendHere??// </div>
<input type="button" value="Show/Hide Legend" onclick="showHideLegend()">
It looks like you were just trying to update the wrong legend config in the chart.js instance object. Here is the correct way.
document.getElementById('hideLEgend').addEventListener('click', function() {
// toggle visibility of legend
myLine.options.legend.display = !myLine.options.legend.display;
myLine.update();
});
The thing that you were trying to update (e.g. chart.legend.options) is just the default legend configuration object. This gets merged with whatever options you define in your chart's options.legend config.
Here is a codepen example showing the legend show/hide behavior from a button click.
You could also opt to not use the built in legend and generate your legend as pure HTML/CSS anywhere on your page, and then use jQuery (or standard javascript) to show and hide. I won't provide an example for the showing/hiding (see jQuery's show/hide functions) but I will demonstrate how to generate a custom legend. First you need to use the options.legendCallback option to create a function that generates the custom legend.
options: {
legend: {
display: false,
position: 'bottom'
},
legendCallback: function(chart) {
var text = [];
text.push('<ul class="' + chart.id + '-legend">');
for (var i = 0; i < chart.data.datasets.length; i++) {
text.push('<li><div class="legendValue"><span style="background-color:' + chart.data.datasets[i].backgroundColor + '"> </span>');
if (chart.data.datasets[i].label) {
text.push('<span class="label">' + chart.data.datasets[i].label + '</span>');
}
text.push('</div></li><div class="clear"></div>');
}
text.push('</ul>');
return text.join('');
}
}
Then use the .generateLegend() prototype method to generate the template (which executes the legendCallback function defined above) and insert it into the DOM.
$('#legend').prepend(mybarChart.generateLegend());
Here is a codepen example that demonstrates the custom legend approach. You can modify the legendCallback function to use whatever HTML you want for the legend structure and then use standard CSS to style it. And finally, use javascript to show/hide it on the button click.
Did you try putting it in a div and hide/show it with CSS? it will be present but hidden and update() will make changes to the existing data so when u want it, just remove class "hidden".
I have a c3.js stacked barchart that updates when you hover over a Leaflet map, and I need the tooltip to be static as otherwise the user will hover over other areas of the map and change the data in the barchart, before actually reaching it. However, I'm new to coding and especially new to C3 and I can't get around how to make the tooltip static. Also, does anyone know how to style the tooltip later? I have only found very complex examples online, but it feels like I should be able to do it somewhere after I generate the chart.
Any help would be much appreciated!
Here is my code:
function getMiniChartData(properties) {
var values = [
['rape', rape[properties['gss_code']]],
['other sexual', other_sexual[properties['gss_code']]]];
console.log(values);
return values;
}
var chart;
function drawMiniChart(properties) {
console.log('drawing mini chart');
var data = getMiniChartData(properties);
chart = c3.generate({
bindto: '#minichart',
color: {
pattern: ['#E31A1C', '#BD0026']
},
point: {
show: false
},
tooltip: {
show: true
},
data: {
columns: data,
type: 'bar',
groups: [
['rape', 'other sexual']
]
},
axis: {
y: {
max:60,
min:0
}
},
grid: {
y: {
lines: [{
value: 0
}]
}
}
});
}
function updateMiniChartData(properties) {
console.log('updating mini chart');
var data = getMiniChartData(properties);
chart.load({
columns: data
});
}
Just edit the position in the tooltip :
position: function () {
var position = c3.chart.internal.fn.tooltipPosition.apply(this, arguments);
position.top = 0;
return position;
}
This will set the tooltip to always be at the top of the point. So it stays at the same y coordinate (top:0) but follows the points x value. You could go further and set it to stay at one position on the page.
Check this fiddle I have put together : http://jsfiddle.net/thatOneGuy/owhxgaqm/185/
This question will help you out : C3 charts - contents of tooltip clickable
If you want it visible all the time just add this code :
var originalHideTooltip = chart.internal.hideTooltip
chart.internal.hideTooltip = function () {
setTimeout(originalHideTooltip, 100)
};
I have kendo-chart at my js code.
By default, the legend area layout is that, there is list of colors, and the right of every color - there is label with series name. I want to reverse the order: put label first, and color second, and align it to right.
I think the best way to do it is by legend.item, but I don't know how to do it.
see the current state:
and here is demo of what I want will be:
You can create a custom legend visual using the Kendo legend methods.
legend: {
item: {
visual: function (e) {
// get the default color for the legend shape
var color = e.options.markers.background;
// get the default color for the legend text
var labelColor = e.options.labels.color;
// bounds of the legend
var rect = new kendo.geometry.Rect([0, 0], [100, 50]);
var layout = new kendo.drawing.Layout(rect, {
spacing: 5,
alignItems: "center"
});
// Recreate the legend shape (can be any shape)
var marker = new kendo.drawing.Path({
fill: {
color: color
}
}).moveTo(10, 0).lineTo(15, 10).lineTo(5, 10).close();
// recreate the label text
var label = new kendo.drawing.Text(e.series.name, [0, 0], {
fill: {
color: labelColor
}
});
// This is the key part: it draws the label first then the shape
layout.append(label, marker);
layout.reflow()
return layout;
}
}
The important part of this code is this part:
layout.append(label, marker);
Because we're specifying the label first, then the marker, the label should appear first.
I don't have a jsFiddle setup for this, but Kendo has an example in their dojo: http://dojo.telerik.com/OdiNi
In this case you'll have hide the legend.
legend: {
visible: false
},
And create your own legend in html.
Using highcharts, I am adding multiple series to an exist chart. When adding the series I need to be able to set tooltip on or off depending on the series added.
Here is where I am at:
widget.chart.addSeries({
data: newSeries,
color: color,
tooltip: {
enabled: true,
formatter: function() {
return 'test';
}
}
});
Try this.
Inside chart options.
tooltip: {
formatter: function() {
var text = false;
if(this.series.name == "GOOG") {
// just an example of serie name
// you can use index or other data too
text = 'test';
}
return text;
}
}
demo