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React forwardRef HoC不提供对容器元素的引用

higher-order-components reactjs javascript

Mario Nikolaus · 技术社区 · 7 年前

在我看来,这可以通过forwardRef和HOC实现,尽管在官方文档中有一个例子,但我似乎无法正确实现。

因此,我希望我的HOC创建对组件容器的引用。它是包装的,因为它有处理程序来跟踪点击并对其进行操作。例如,假设我们有一个通用的下拉组件,人们会期望我可以在该组件区域之外的任何单击上关闭它。

我目前拥有的代码:

import React from 'react';

function withClose(Component) {
 class ClickContainer extends React.Component {
    constructor() {
      super();
      this.handleClose = this.handleClose.bind(this);
    }

    componentDidMount() {
      document.addEventListener('click', this.handleClose);
    }

    componentWillUnmount() {
      document.removeEventListener('click', this.handleClose);
    }

    handleClose(e) {
      // I expect having here context of container of wrapped component to do something like
      const { forwardedRef } = this.props; // <- I expect having context in forwardedRef variable
    }

    render() {
      const { forwardedRef, ...rest } = this.props;
      return <Component ref={forwardedRef} {...rest} />;
    }
  }

  return React.forwardRef((props, ref) => {
    return <ClickContainer {...props} forwardedRef={ref} />;
  });
}

export default withClose;

我错过了什么?我不能让它工作,我只得到包装组件的上下文,而不是元素本身。

非常感谢!

2 回复 | 直到 7 年前

Orar 7 年前

Ref应该传递给元素

https://codesandbox.io/s/7yzoqm747x

假设

export const Popup = (props,) => {
  const { name, forwardRef } = props;
  return (
   <div ref={forwardRef}>  // You need to pass it down from props
     {name}
   </div>
  )
}

以及特别组织

export function withClose(Component) {
  class ClickContainer extends React.Component {
    constructor() {
     super();
     this.handleClose = this.handleClose.bind(this);
    }

    componentDidMount() {
      document.addEventListener('click', this.handleClose);
    }

    componentWillUnmount() {
      document.removeEventListener('click', this.handleClose);
    }

    handleClose(e) { 
     const { forwardRef } = this.props;
     console.log(forwardRef);
    }

    render() {
      const { forwardRef, ...rest } = this.props;
      return <Component forwardRef={forwardRef} {...rest} />;
    }
  }

  return React.forwardRef((props, ref) => {
    return <ClickContainer {...props} forwardRef={ref} />;
  });
}

 const CloseablePopup = withClose(Popup);

  class App extends Component {
    popupRef = React.createRef();
    render() {
      return (<CloseablePopup ref={popupRef} name="Closable Popup" />);
    }
  }

tubu13 7 年前

几天前我实现了同样的事情。我想要一个把手 onClickoutside

我希望该组件在每次单击时检查子对象是否单击,以及是否调用子对象上的函数。

import React from 'react';

export default function withClickOutside(WrappedComponent) {
  class WithClickOutside extends WrappedComponent {
    constructor(props) {
      super(props);
      this.handleClickOutside = this.handleClickOutside.bind(this);
      this.wrappedElement = React.createRef();
    }

    componentDidMount() {
      document.addEventListener('click', this.handleClickOutside, true);
    }

    componentWillUnmount() {
      document.removeEventListener('click', this.handleClickOutside, true);
    }


    handleClickOutside(event) {
       if (event.type !== 'click') return;
       if (!this.wrappedElement.current) {
          throw new Error(`No ref for element ${WrappedComponent.name}. Please create ref when using withClickOutside`);
        }

      if (!this.wrappedElement.current.contains(event.target)) {
         if (!this.onClickOutside) {
           throw new Error(`${WrappedComponent.name} does not implement onClickOutside function. Please create onClickOutside function when using withClickOutside`);
         }

       this.onClickOutside(event);
     }
   }


   render() {
     const wrapped = super.render();
     const element = React.cloneElement(
       wrapped,
       { ref: this.wrappedElement },
     );

     return element;
   }
 }

 return WithClickOutside;
}

onClickOutside .