Cannot assign to read only property 'data' of object

See original GitHub issue

When using heatmap.js on certain browsers, this error Cannot assign to read only property 'data' of object shows up. screen shot 2016-09-01 at 11 18 47 am

I’m able to reproduce on chromium that is packaged with electron version 1.3.3.

This seems to happen because the data property of ImageData object is being replaced directly in this part of the code. https://github.com/pa7/heatmap.js/blob/master/src/renderer/canvas2d.js#L280

data property seems to be read only on certain browser versions. To fix it, we need to delete this line because imgData and img.data points to the same reference. Any modifications you do to imgData is already reflected to img.data. I’ll put up a PR soon.

Issue Analytics

State:
Created 7 years ago
Reactions:8
Comments:13

Top GitHub Comments

11reactions

njifarescommented, Aug 8, 2019

I’m facing the same issue using heatmapjs in my Angular application.

1reaction

iaaseihycommented, May 12, 2022

so how can this problem be solved in version 2.0.5

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