反应长按事件 [英] react long press event

问题描述

是否可以在反应网络应用程序中添加长按事件？

Is there a way to add long press event in react-web application?

我有列表地址。长按任意一个地址，我都想触发事件以删除该地址，并在其后单击确认框。

I have list of addresses. On long press on any address, I want to fire event to delete that address followed by a confirm box.

推荐答案

我已经创建了一个 codesandbox ，并带有一个钩子来处理长按并单击。基本上，在鼠标按下时触摸启动事件，将使用 setTimeout 创建一个计时器。经过规定的时间后，将触发长按。
在鼠标悬停，鼠标离开，触摸结束等情况下，计时器将清除。

I've created a codesandbox with a hook to handle long press and click. Basically, on mouse down, touch start events, a timer is created with setTimeout. When the provided time elapses, it triggers long press. On mouse up, mouse leave, touchend, etc, the timer is cleared.

useLongPress.js

import { useCallback, useRef, useState } from "react";

const useLongPress = (
    onLongPress,
    onClick,
    { shouldPreventDefault = true, delay = 300 } = {}
    ) => {
    const [longPressTriggered, setLongPressTriggered] = useState(false);
    const timeout = useRef();
    const target = useRef();

    const start = useCallback(
        event => {
            if (shouldPreventDefault && event.target) {
                    event.target.addEventListener("touchend", preventDefault, {
                    passive: false
                });
                target.current = event.target;
            }
            timeout.current = setTimeout(() => {
                onLongPress(event);
                setLongPressTriggered(true);
            }, delay);
        },
        [onLongPress, delay, shouldPreventDefault]
    );

    const clear = useCallback(
        (event, shouldTriggerClick = true) => {
            timeout.current && clearTimeout(timeout.current);
            shouldTriggerClick && !longPressTriggered && onClick();
            setLongPressTriggered(false);
            if (shouldPreventDefault && target.current) {
                target.current.removeEventListener("touchend", preventDefault);
            }
        },
        [shouldPreventDefault, onClick, longPressTriggered]
    );

    return {
        onMouseDown: e => start(e),
        onTouchStart: e => start(e),
        onMouseUp: e => clear(e),
        onMouseLeave: e => clear(e, false),
        onTouchEnd: e => clear(e)
    };
};

const isTouchEvent = event => {
return "touches" in event;
};

const preventDefault = event => {
if (!isTouchEvent(event)) return;

if (event.touches.length < 2 && event.preventDefault) {
    event.preventDefault();
}
};

export default useLongPress;

要使用该钩子，
App.js

import useLongPress from "./useLongPress";

export default function App() {

    const onLongPress = () => {
        console.log('longpress is triggered');
    };

    const onClick = () => {
        console.log('click is triggered')
    }

    const defaultOptions = {
        shouldPreventDefault: true,
        delay: 500,
    };
    const longPressEvent = useLongPress(onLongPress, onClick, defaultOptions);

    return (
        <div className="App">
            <button {...longPressEvent}>use  Loooong  Press</button>
        </div>
    );
}

班级组成部分的较早答案：

您可以使用MouseDown，MouseUp，TouchStart，TouchEnd事件来控制可以用作长按事件的计时器。看看下面的代码

You can use MouseDown, MouseUp, TouchStart, TouchEnd events to control timers that can act as a long press event. Check out the code below

class App extends Component {
  constructor() {
    super()
    this.handleButtonPress = this.handleButtonPress.bind(this)
    this.handleButtonRelease = this.handleButtonRelease.bind(this)
  }
  handleButtonPress () {
    this.buttonPressTimer = setTimeout(() => alert('long press activated'), 1500);
  }
  
  handleButtonRelease () {
    clearTimeout(this.buttonPressTimer);
  }

  render() {
    return (
      <div 
          onTouchStart={this.handleButtonPress} 
          onTouchEnd={this.handleButtonRelease} 
          onMouseDown={this.handleButtonPress} 
          onMouseUp={this.handleButtonRelease} 
          onMouseLeave={this.handleButtonRelease}>
        Button
      </div>
    );
  }
}

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