[更新]使用挂钩的React ^16.8解决方案

代码沙盒

import React, { useEffect, useRef, useState } from 'react';

const SampleComponent = () => {
    const [clickedOutside, setClickedOutside] = useState(false);
    const myRef = useRef();

    const handleClickOutside = e => {
        if (!myRef.current.contains(e.target)) {
            setClickedOutside(true);
        }
    };

    const handleClickInside = () => setClickedOutside(false);

    useEffect(() => {
        document.addEventListener('mousedown', handleClickOutside);
        return () => document.removeEventListener('mousedown', handleClickOutside);
    });

    return (
        <button ref={myRef} onClick={handleClickInside}>
            {clickedOutside ? 'Bye!' : 'Hello!'}
        </button>
    );
};

export default SampleComponent;

反应溶液^16.3：

代码沙盒

import React, { Component } from "react";

class SampleComponent extends Component {
  state = {
    clickedOutside: false
  };

  componentDidMount() {
    document.addEventListener("mousedown", this.handleClickOutside);
  }

  componentWillUnmount() {
    document.removeEventListener("mousedown", this.handleClickOutside);
  }

  myRef = React.createRef();

  handleClickOutside = e => {
    if (!this.myRef.current.contains(e.target)) {
      this.setState({ clickedOutside: true });
    }
  };

  handleClickInside = () => this.setState({ clickedOutside: false });

  render() {
    return (
      <button ref={this.myRef} onClick={this.handleClickInside}>
        {this.state.clickedOutside ? "Bye!" : "Hello!"}
      </button>
    );
  }
}

export default SampleComponent;

我在discuss.reactjs.org上找到了一个解决方案，这要感谢Ben Alpert。单击我的树中的一个组件会导致一个重新阅读程序，在更新时删除了单击的元素。由于React的重读发生在调用文档正文处理程序之前，因此元素未被检测为“在”树中。

解决方案是在应用程序根元素上添加处理程序。

主要：

window.__myapp_container = document.getElementById('app')
React.render(<App/>, window.__myapp_container)

组件：

import { Component, PropTypes } from 'react';
import ReactDOM from 'react-dom';

export default class ClickListener extends Component {

  static propTypes = {
    children: PropTypes.node.isRequired,
    onClickOutside: PropTypes.func.isRequired
  }

  componentDidMount () {
    window.__myapp_container.addEventListener('click', this.handleDocumentClick)
  }

  componentWillUnmount () {
    window.__myapp_container.removeEventListener('click', this.handleDocumentClick)
  }

  /* using fat arrow to bind to instance */
  handleDocumentClick = (evt) => {
    const area = ReactDOM.findDOMNode(this.refs.area);

    if (!area.contains(evt.target)) {
      this.props.onClickOutside(evt)
    }
  }

  render () {
    return (
      <div ref='area'>
       {this.props.children}
      </div>
    )
  }
}

除了.concurs之外，还可以使用最接近的方法。当您想检查单击是否在id=“apple”的元素之外时，我可以使用：

const isOutside = !e.target.closest("#apple");

这将检查单击的树上方的树中是否有任何元素的id为“apple”。我们必须否定结果！

要使“焦点”解决方案适用于带有事件侦听器的下拉列表，您可以使用onMouseDown事件而不是onClick来添加它们。这样，事件将启动，之后弹出窗口将关闭，如下所示：

<TogglePopupButton
                    onClick = { this.toggleDropup }
                    tabIndex = '0'
                    onBlur = { this.closeDropup }
                />
                { this.state.isOpenedDropup &&
                <ul className = { dropupList }>
                    { this.props.listItems.map((item, i) => (
                        <li
                            key = { i }
                            onMouseDown = { item.eventHandler }
                        >
                            { item.itemName}
                        </li>
                    ))}
                </ul>
                }

使用OnClickOutside Hook-反应16.8+

创建通用useOnOutsideClick函数

export const useOnOutsideClick = handleOutsideClick => {
  const innerBorderRef = useRef();

  const onClick = event => {
    if (
      innerBorderRef.current &&
      !innerBorderRef.current.contains(event.target)
    ) {
      handleOutsideClick();
    }
  };

  useMountEffect(() => {
    document.addEventListener("click", onClick, true);
    return () => {
      document.removeEventListener("click", onClick, true);
    };
  });

  return { innerBorderRef };
};

const useMountEffect = fun => useEffect(fun, []);

然后在任何功能组件中使用钩子。

const OutsideClickDemo = ({ currentMode, changeContactAppMode }) => {

  const [open, setOpen] = useState(false);
  const { innerBorderRef } = useOnOutsideClick(() => setOpen(false));

  return (
    <div>
      <button onClick={() => setOpen(true)}>open</button>
      {open && (
        <div ref={innerBorderRef}>
           <SomeChild/>
        </div>
      )}
    </div>
  );

};

链接到演示

部分灵感来自于@pau1itzgerald的回答。

非侵入性方式无需添加另一个DIV EL。

注意：React可能会说findDomNode已弃用，但到目前为止，我还没有遇到任何问题

@异常：单击要忽略的类

@idException:单击时忽略的id

import React from "react"
import ReactDOM from "react-dom"
type Func1<T1, R> = (a1: T1) => R


export function closest(
    el: Element,
    fn: (el: Element) => boolean
  ): Element | undefined {
    let el_: Element | null = el;
  
    while (el_) {
      if (fn(el_)) {
        return el_;
      }
  
      el_ = el_.parentElement;
    }
  }
let instances: ClickOutside[] = []

type Props = {
  idException?: string,
  exceptions?: (string | Func1<MouseEvent, boolean>)[]
  handleClickOutside: Func1<MouseEvent, void>

}


export default class ClickOutside extends React.Component<Props> {
  static defaultProps = {
    exceptions: []
  };

  componentDidMount() {
    if (instances.length === 0) {
      document.addEventListener("mousedown", this.handleAll, true)
      window.parent.document.addEventListener(
        "mousedown",
        this.handleAll,
        true
      )
    }
    instances.push(this)
  }

  componentWillUnmount() {
    instances.splice(instances.indexOf(this), 1)
    if (instances.length === 0) {
      document.removeEventListener("mousedown", this.handleAll, true)
      window.parent.document.removeEventListener(
        "mousedown",
        this.handleAll,
        true
      )
    }
  }

  handleAll = (e: MouseEvent) => {

    const target: HTMLElement = e.target as HTMLElement
    if (!target) return

    instances.forEach(instance => {
      const { exceptions, handleClickOutside: onClickOutside, idException } = instance.props as Required<Props>
      let exceptionsCount = 0

      if (exceptions.length > 0) {
        const { functionExceptions, stringExceptions } = exceptions.reduce(
          (acc, exception) => {
            switch (typeof exception) {
              case "function":
                acc.functionExceptions.push(exception)
                break
              case "string":
                acc.stringExceptions.push(exception)
                break
            }

            return acc
          },
          { functionExceptions: [] as Func1<MouseEvent, boolean>[], stringExceptions: [] as string[] }
        )
        if (functionExceptions.length > 0) {
          exceptionsCount += functionExceptions.filter(
            exception => exception(e) === true
          ).length
        }

        if (exceptionsCount === 0 && stringExceptions.length > 0) {

          const el = closest(target, (e) => stringExceptions.some(ex => e.classList.contains(ex)))
          if (el) {
            exceptionsCount++
          }
        }
      }

      if (idException) {
        const target = e.target as HTMLDivElement
        if (document.getElementById(idException)!.contains(target)) {
          exceptionsCount++
        }
      }

      if (exceptionsCount === 0) {
        // eslint-disable-next-line react/no-find-dom-node
        const node = ReactDOM.findDOMNode(instance)

        if (node && !node.contains(target)) {
          onClickOutside(e)
        }
      }
    })
  };

  render() {
    return React.Children.only(this.props.children)
  }
}

用法

<ClickOutside {...{ handleClickOutside: () => { alert('Clicked Outside') } }}>
    <div >
        <div>Breathe</div>
    </div>
</ClickOutside>