如何创建具有锁定y轴的水平滚动Chart.js折线图？
问题描述：
我想用 Chart.Js 创建折线图，但是 Y轴不要移动当我滚动时。
I'd like to create a line chart with Chart.Js but have the Y-Axis not move when I scroll.
我假设我可以使用固定宽度，并将其放在容器div中 overflow：auto ，但随后 Y轴信息附加到画布并滚动。
I'm assuming I can use a fixed width, and put it in a container div with overflow:auto, but then The Y-axis info is attached to the canvas and scrolls along.
我没有在文档中看到这方面的参数或选项。有什么想法吗？
I don't see a parameter or option for this in the docs. Any ideas?
谢谢
答
可滚动图表
你几乎走在正确的轨道上。如果你添加了另一个包装器和y轴，你就完成了。
Scrollable Chart
You're pretty much on the right track. If you add another wrapper and the y axis you are done.
预览
CSS
.chartWrapper {
position: relative;
}
.chartWrapper > canvas {
position: absolute;
left: 0;
top: 0;
pointer-events:none;
}
.chartAreaWrapper {
width: 600px;
overflow-x: scroll;
}
HTML
<div class="chartWrapper">
<div class="chartAreaWrapper">
<canvas id="myChart" height="300" width="1200"></canvas>
</div>
<canvas id="myChartAxis" height="300" width="0"></canvas>
</div>
脚本
...
new Chart(ctx).Line(data, {
onAnimationComplete: function () {
var sourceCanvas = this.chart.ctx.canvas;
// the -5 is so that we don't copy the edges of the line
var copyWidth = this.scale.xScalePaddingLeft - 5;
// the +5 is so that the bottommost y axis label is not clipped off
// we could factor this in using measureText if we wanted to be generic
var copyHeight = this.scale.endPoint + 5;
var targetCtx = document.getElementById("myChartAxis").getContext("2d");
targetCtx.canvas.width = copyWidth;
targetCtx.drawImage(sourceCanvas, 0, 0, copyWidth, copyHeight, 0, 0, copyWidth, copyHeight);
}
});