I'd like to create a line chart with Chart.Js
but have the Y-Axis
not move when I scroll.
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.
I don't see a parameter or option for this in the docs. Any ideas?
Thank you
You're pretty much on the right track. If you add another wrapper and the y axis you are done.
Preview
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>
Script
...
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);
}
});
Fiddle - http://jsfiddle.net/mbhavfwm/