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Adding Accessibility page #5719

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1 change: 1 addition & 0 deletions docs/SUMMARY.md
Expand Up @@ -6,6 +6,7 @@
* [Integration](getting-started/integration.md)
* [Usage](getting-started/usage.md)
* [General](general/README.md)
* [Accessibility](general/accessibility.md)
* [Responsive](general/responsive.md)
* [Pixel Ratio](general/device-pixel-ratio.md)
* [Interactions](general/interactions/README.md)
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39 changes: 39 additions & 0 deletions docs/general/accessibility.md
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# Accessible Charts

Chart.js charts are rendered on user provided `canvas` elements. Thus it is up to the user to create the `canvas` element in a way that is accessible. The `canvas` element has support in all browsers and will render on screen but the `canvas` content will not be accessible to screen readers.
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nit: it should be on a user provided

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I used plural charts and plural elements. I believe that is grammatically correct.


With `canvas`, the accessibility has to be added with JavaScript for `ARIA` attributes on the `canvas` element or added using internal fallback content placed within the opening and closing canvas tag.
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This [website](http://pauljadam.com/demos/canvas.html) has a more detailed explanation of `canvas` accessibility as well as in depth examples.

## Examples

These are some examples of **accessible** `canvas` elements.

By setting the `role` and `aria-label`, this `canvas` now has an accessible name.

```html
<canvas id="goodCanvas1" width="400" height="100" aria-label="Hello ARIA World" role="img"></canvas>
```

This `canvas` element has a text alternative via fallback content.

```html
<canvas id="okCanvas2" width="400" height="100">
<p>Hello Fallback World</p>
</canvas>
```

These are some bad examples of **inaccessible** `canvas` elements.

This `canvas` element does not have an accessible name or role.

```html
<canvas id="badCanvas1" width="400" height="100"></canvas>
```

This `canvas` element has inaccessible fallback content.

```html
<canvas id="badCanvas2" width="400" height="100">Your browser does not support the canvas element.</canvas>
```