在React.js中使用SVG过滤器属性

Question

I have been researching a bit on data representation with SVG and React and they seem a perfect fit. However SVG is not yet supported in React, and an addon does not exist yet https://github.com/facebook/react/issues/2250 .

Yet there is some workarounds like using dangerouslySetInnerHTML for some elements, in my case I cannot find one yet.

I want to use filter attribute inside a circle svg element. However It gets not rendered into the DOM. Here it is my React Component:

class DeviceDot extends React.Component {
  render () {
    const { app, idx } = this.props

    return  <circle cx={50 * idx} cy={50 * idx} r='25' filter={`url(#${app})`} fill='mediumorchid' />
  }
}

And the filter:

class FilterSVG extends React.Component {
  render () {
    const { app, idx } = this.props
    const icon = app ? `/api/apps/${app}/logo` : '/img/dflt.png'

    return (
      <filter id={app || 'default'} x='0%' y='0%' width='100%' height='100%'>
        <feImage xlinkHref={icon} />
      </filter>
    )
  }
}

However I cannot use dangerouslySetInnerHTML without wrapping this component, which I want to reuse as is (a circle SVG element). Is there any work around to use this attribute (and others) you are using right now?

Thank you.

Answer 1

For filter you can use CSS styles as workaround, like this:

const style = {
  filter: `url(#${app || 'default'})`
}

And the returning component...

return <circle cx={50 * idx} cy={50 * idx} r='25' style={style} />

If you only want to filter you can use plain CSS. Thus, add it to React props.

Answer 2

React does support SVG. The issue you've linked to has been fixed. In some cases the JSX attribute will be different to the HTML attribute, eg xlinkHref instead of xlink:href . It should not be necessary to use dangerouslySetInnerHTML .

In the code above, it looks as if you're simply using the wrong variable. You want this instead:

filter={`url(#${icon})`}