How to show data values or index labels in ChartJs (Latest Version) as in the below image:
I am using the ChartJs to display charts in my React Project. Everything is working fine, except this.
I found an answer in stackoverflow (https://stackoverflow.com/a/31632707), But it uses an old version of chartjs and is not working on the one which I am using.
My ChartJs Code:
var ctx = document.getElementById("myChart");
var BarChart = new Chart(ctx, {
type: 'bar',
data: {
labels: ["Jan","Feb","March"],
datasets: [{
label: "Chart Data",
data: [10,20,15],
backgroundColor: "red",
borderColor: "green",
borderWidth: 1
}]
},
options: {
legend: {
display: false
},
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}],
xAxes: [{
ticks: {
maxRotation: 180
}
}]
}
}
});
I tried adding it using the function: ctx.fillText(bar.value, bar.x, bar.y - 5);
, But its showing .fillText is not a function
Finally I got it working.
Used the following code in the onComplete() function:
animation: {
onComplete: function () {
var ctx = this.chart.ctx;
ctx.font = Chart.helpers.fontString(Chart.defaults.global.defaultFontFamily, 'normal', Chart.defaults.global.defaultFontFamily);
ctx.fillStyle = "black";
ctx.textAlign = 'center';
ctx.textBaseline = 'bottom';
this.data.datasets.forEach(function (dataset)
{
for (var i = 0; i < dataset.data.length; i++) {
for(var key in dataset._meta)
{
var model = dataset._meta[key].data[i]._model;
ctx.fillText(dataset.data[i], model.x, model.y - 5);
}
}
});
}
}
Got it to work after some researching.
You have to set it after in the onComplete
event of the animation.
The x, y values of the bars are stored in the model of the children (point, line, bar, whatever)
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++) {
console
var model = dataset._meta[0].dataset._children[i]._model;
ctx.fillText(dataset.data[i], model.x, model.y - 5);
}
});
}
Just the structure changed a little bit.
You can see it in this working JSFiddle
来源:https://stackoverflow.com/questions/38344582/how-to-show-data-values-or-index-labels-in-chartjs-latest-version