Converting Chart.js canvas chart to image using .toDataUrl() results in blank image

canvas, chart.js, html, javascript

Solution

The chart seem to be async so you will probably need to provide a callback when the animation has finished or else the canvas will be empty.

var options = {
    bezierCurve : false,
    onAnimationComplete: done  /// calls function done() {} at end
};

Problem

I am using Chart.js. I am trying to convert the chart to an image by getting a base 64 string. The tutorial (http://www.chartjs.org/docs/) devotes an entire 1 line on the topic: The canvas element also allows for saving the contents as a base 64 string, allowing saving the chart as an image. A `canvas` element has the method of `toDataURL`, which returns a base64 string of the image. However, when I do that, the image it renders is just a transparent rectangle with the dimensions of the chart, and it does not include the chart contents. Here is a fiddle: http://jsfiddle.net/KSgV7/ The "images" in the fiddle are styled with a black border, so you can see where they are supposed to be, since they seem to just be a big transparent block. Has anyone successfully converted a Chart.js chart to an image?

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