React 16.6 StrictMode: findDOMNode is deprecated in StrictMode

First of all, thanks for your package. It’s quite a help to have it.

I just checked out the latest react 16.6.0 release. They extended APIs in StrictMode, that are now considered deprecated. findDOMNode is now considered deprecated. See https://reactjs.org/blog/2018/10/23/react-v-16-6.html#deprecations-in-strictmode for the full list.

If you add React.StrictMode around Slick you’ll get the following console warning:

Warning: findDOMNode is deprecated in StrictMode. findDOMNode was passed an instance of Track which is inside StrictMode. Instead, add a ref directly to the element you want to reference.

    in div (created by Track)
    in Track (created by InnerSlider)
    in div (created by InnerSlider)
    in div (created by InnerSlider)
    in InnerSlider (created by Slider)
    in Slider (created by ReactSlickDemo)
    in div (created by ReactSlickDemo)
    in StrictMode (created by ReactSlickDemo)
    in ReactSlickDemo

Learn more about using refs safely here:
https://fb.me/react-strict-mode-find-node

See it live on https://codesandbox.io/s/8j39k1pq8. Also see https://fb.me/react-strict-mode-find-node for how to get rid of the warning.

[remidej]

Pinging this issue, since strict mode is becoming more necessary with React concurrent mode coming up. @akiran could you review #1442 ?

[andreytrofimov]

Hi @akiran Could you check PR #1442 to fix this issue?