i am using chartjs lastest version (2.6.0). I just have a simple question that I want to get each bar width but i can not find the answer anywhere. Could someone please help me. Thanks alot. Here is simple bar chart.
var ctx = document.getElementById("myChart").getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3]
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.6.0/Chart.min.js"></script>
<canvas class="canvasChart" id="myChart"></canvas>
You can get each bar's width (basically the same) in ChartJS, using .getDatasetMeta() method.
var ctx = document.getElementById("myChart").getContext('2d');
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3]
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
}
}
});
function getWidth() {
var barWidth = myChart.getDatasetMeta(0).data[0]._view.width;
alert(barWidth);
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.6.0/Chart.min.js"></script>
<button onclick="getWidth()">Get Bar Width</button>
<canvas class="canvasChart" id="myChart"></canvas>
Related
I am using Chart.js to draw a simple line chart.
How can I make small grid lines on top of the xAxis labels?
The documentation for Line Chart is here: https://www.chartjs.org/docs/2.7.3/getting-started/?h=line, but I can't find anything about it.
I removed the XAxis and YAxis grid lines.
This is an example of the small grid lines wanted:
Thanks in advance.
Instead of removing the gridlines you can set the drawOnChartArea to false:
var options = {
type: 'line',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 3],
borderColor: 'pink'
},
{
label: '# of Points',
data: [7, 11, 5, 8, 3, 7],
borderColor: 'orange'
}
]
},
options: {
scales: {
x: {
grid: {
drawOnChartArea: false
}
},
y: {
grid: {
drawOnChartArea: false
}
}
}
},
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.6.2/chart.js"></script>
</body>
Is it possible to create a chart like this (following image) using Chart.js version 3?
Any suggestions would be greatly appreciated.
You can stack the x axis together with a smaller bar percentage for the inner bar:
const options = {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Points',
data: [7, 11, 5, 8, 3, 7],
backgroundColor: 'orange',
barPercentage: 0.6
},
{
label: '# of Votes',
data: [12, 19, 8, 10, 5, 13],
backgroundColor: 'pink'
}
]
},
options: {
scales: {
x: {
stacked: true
}
}
}
}
const ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.6.2/chart.js"></script>
</body>
I read many threads on the beginAtZero parameter in Chart.js, but none of the solutions I found actually work for me.
I have a simple line chart with dates on my x axe and integers in my y axe. I can't manage to make my y axe start with 0.
let atchoum = document.querySelector("#atchoum")
let statchoum = new Chart(atchoum, {
type: "line",
data: {
labels: {{ atchoumDate|raw }},
datasets: [{
label: "Nombre d'éternuements au support",
data: {{ atchoumNb|raw }},
borderColor: "blue",
tension: 0.3,
options: {
responsive: true,
scales: {
y: {
beginAtZero: true
}
},
animations: {
y: {
easing: 'easeInOutElastic',
from: (ctx) => {
if (ctx.type === 'data') {
if (ctx.mode === 'default' && !ctx.dropped) {
ctx.dropped = true;
return 0;
}
}
}
}
},
}
}]
}
})
You are defining your options in the dataset itself.
The options object is supposed to be on the same level as the type and data fields since the options are for the entire chart and not for a single dataset.
const options = {
type: 'line',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: '# of Votes',
data: [12, 19, 7, 9, 20, 8]
}]
},
options: {
scales: {
y: {
beginAtZero: true
}
}
}
}
const ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.5.1/chart.js"></script>
</body>
I'm creating an stack bar chart using chart.js. I need to hide the labels which don't have data on the current chart. As an example I want to only show "Prediction Success" label as data related to other labels are not there for the current date range. How can we do that?
You can use the legend filter like this:
var options = {
type: 'bar',
data: {
labels: ["Red", "Yellow", "Blue", "Yellow", "Green", "Purple", "Orange", "Green"],
datasets: [{
label: '# of Votes',
data: [12, 19, 3, 5, 2, 0, 5, 6],
borderWidth: 1,
backgroundColor: 'red'
},
{
label: '# of NonVotes',
data: [],
borderWidth: 1,
backgroundColor: 'blue'
}
]
},
options: {
plugins: {
legend: {
labels: {
filter: (legendItem, chartData) => (legendItem, chartData, chartData.datasets[legendItem.datasetIndex].data.length > 0)
}
}
}
}
}
var ctx = document.getElementById('chartJSContainer').getContext('2d');
new Chart(ctx, options);
<body>
<canvas id="chartJSContainer" width="600" height="400"></canvas>
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/3.1.0/chart.js" integrity="sha512-LlFvdZpYhQdASf4aZfSpmyHD6+waYVfJRwfJrBgki7/Uh+TXMLFYcKMRim65+o3lFsfk20vrK9sJDute7BUAUw==" crossorigin="anonymous"></script>
</body>
I need to set the serifs on the X and Y axes like on image.
I try to find this feature in docs but found nothing.
options -> axes -> ticks have font properties, which you can set/change before or afterwards.
var ctx = document.getElementById("myChart");
var myChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Red", "Blue", "Yellow", "Green", "Purple", "Orange"],
datasets: [{
label: 'some numbers',
data: [5, 1, 3, 2, 4, 1],
backgroundColor: ["red", "blue", "yellow", "green", "purple", "orange"],
}]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero:true
}
}],
yAxes: [{
ticks: {
fontSize: "14"
}
}]
}
}
});
document.getElementById("testbtn").addEventListener("click", function() {
myChart.options.scales.yAxes[0].ticks.fontStyle = "bold";
myChart.options.scales.xAxes[0].ticks.fontFamily = "Verdana";
myChart.options.scales.xAxes[0].ticks.fontColor = "red";
myChart.update();
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.7.3/Chart.min.js"></script>
<canvas id="myChart" height="50"></canvas>
<br>
<button id="testbtn">change font</button>