'use strict'; /** * imported from react-native */ import type { MutableRefObject } from 'react'; /* eslint-disable */ /** * This is a helper function for when a component needs to be able to forward a ref * to a child component, but still needs to have access to that component as part of * its implementation. * * Its main use case is in wrappers for native components. * * Usage: * * class MyView extends React.Component { * _nativeRef = null; * * _setNativeRef = setAndForwardRef({ * getForwardedRef: () => this.props.forwardedRef, * setLocalRef: ref => { * this._nativeRef = ref; * }, * }); * * render() { * return ; * } * } * * const MyViewWithRef = React.forwardRef((props, ref) => ( * * )); * * module.exports = MyViewWithRef; */ /* eslint-enable */ type ForwardedRef = () => MutableRefObject | ((ref: T) => void); function setAndForwardRef({ getForwardedRef, setLocalRef, }: { getForwardedRef: ForwardedRef; setLocalRef: (ref: T) => void; }): (ref: T) => void { return function forwardRef(ref: T) { const forwardedRef = getForwardedRef(); setLocalRef(ref); // Forward to user ref prop (if one has been specified) if (typeof forwardedRef === 'function') { // Handle function-based refs. String-based refs are handled as functions. forwardedRef(ref); } else if (typeof forwardedRef === 'object' && forwardedRef != null) { // Handle createRef-based refs forwardedRef.current = ref; } }; } export default setAndForwardRef;