import React , { useCallback } from 'react' ; import { Fader } from './Fader' ; import { Mixer } from '../../Mixer' ; function XFader ( { mixer , className } ) { const handleChange = useCallback ( ( v ) => { mixer . xFaderPos = v ; } , [ mixer ] ) ; return < Fader midiParamName = "XFader" onChange = { handleChange } className = { className } / > ; } export { XFader } ;