如何使用 chart.js 和 chartjs-node-canvas 在 PDF 的条形顶部显示值?
How to show values on top of bars in a PDF using chart.js and chartjs-node-canvas?
我需要使用 chartjs-node-canvas 在 Node
中创建 PDF 来显示条形顶部的值
我已经能够重新创建我在 HTML 中看到的内容,但是插件有不接受“动画”的限制 属性,因此我想知道是否有是另一种在 Node 中执行此操作的方法,无需其他外部插件。 This is my current code
var ctx = document.getElementById("myChart");
var chart = new Chart(ctx, {
type: "bar",
data: {
labels: ["a", "b", "c", "d", "e", "f"],
datasets: [
{
type: "bar",
backgroundColor: "blue",
borderColor: "blue",
borderWidth: 1,
label: "promedio",
order: 1,
data: [60, 49, 72, 90, 100, 60]
},
{
type: "bar",
backgroundColor: "orange",
borderColor: "orange",
borderWidth: 1,
label: "promedio",
order: 1,
data: [40, 5, 20, 30, 10, 6]
},
{
type: "line",
label: "casos",
data: [25, 13, 30, 35, 25, 40],
lineTension: 0,
backgroundColor: "red",
borderColor: "red",
order: 0,
fill: false
}
]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
},
animation: {
duration: 1,
onComplete: function () {
var chartInstance = this.chart,
ctx = chartInstance.ctx;
ctx.font = Chart.helpers.fontString(16, 20, Chart.defaults.global.defaultFontFamily);
ctx.textAlign = 'center';
ctx.textBaseline = 'bottom';
this.data.datasets.forEach(function (dataset, i) {
var meta = chartInstance.controller.getDatasetMeta(i);
meta.data.forEach(function (bar, index) {
var data = dataset.data[index];
ctx.fillText(data, bar._model.x, bar._model.y - 2);
});
});
}
},
legend: {
display: false
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<body>
<canvas id="myChart" width="400" height="200"></canvas>
</body>
简短的回答是否定的,您要么必须实现自己的外部内联插件,要么使用数据标签插件 (https://chartjs-plugin-datalabels.netlify.app/samples/charts/bar.html),因为没有内置的方法来实现这个
我需要使用 chartjs-node-canvas 在 Node
中创建 PDF 来显示条形顶部的值我已经能够重新创建我在 HTML 中看到的内容,但是插件有不接受“动画”的限制 属性,因此我想知道是否有是另一种在 Node 中执行此操作的方法,无需其他外部插件。 This is my current code
var ctx = document.getElementById("myChart");
var chart = new Chart(ctx, {
type: "bar",
data: {
labels: ["a", "b", "c", "d", "e", "f"],
datasets: [
{
type: "bar",
backgroundColor: "blue",
borderColor: "blue",
borderWidth: 1,
label: "promedio",
order: 1,
data: [60, 49, 72, 90, 100, 60]
},
{
type: "bar",
backgroundColor: "orange",
borderColor: "orange",
borderWidth: 1,
label: "promedio",
order: 1,
data: [40, 5, 20, 30, 10, 6]
},
{
type: "line",
label: "casos",
data: [25, 13, 30, 35, 25, 40],
lineTension: 0,
backgroundColor: "red",
borderColor: "red",
order: 0,
fill: false
}
]
},
options: {
scales: {
yAxes: [{
ticks: {
beginAtZero: true
}
}]
},
animation: {
duration: 1,
onComplete: function () {
var chartInstance = this.chart,
ctx = chartInstance.ctx;
ctx.font = Chart.helpers.fontString(16, 20, Chart.defaults.global.defaultFontFamily);
ctx.textAlign = 'center';
ctx.textBaseline = 'bottom';
this.data.datasets.forEach(function (dataset, i) {
var meta = chartInstance.controller.getDatasetMeta(i);
meta.data.forEach(function (bar, index) {
var data = dataset.data[index];
ctx.fillText(data, bar._model.x, bar._model.y - 2);
});
});
}
},
legend: {
display: false
}
}
});
<script src="https://cdnjs.cloudflare.com/ajax/libs/Chart.js/2.9.3/Chart.min.js"></script>
<body>
<canvas id="myChart" width="400" height="200"></canvas>
</body>
简短的回答是否定的,您要么必须实现自己的外部内联插件,要么使用数据标签插件 (https://chartjs-plugin-datalabels.netlify.app/samples/charts/bar.html),因为没有内置的方法来实现这个