如何检测用户用JavaScript在网页上向某个方向滑动手指?

我想知道是否有一种解决方案可以同时适用于iPhone和Android手机上的网站。


当前回答

我之前使用的方法是,您必须检测mousedown事件,记录其x,y位置(任何相关的位置),然后检测mouseup事件,并减去两个值。

其他回答

我之前使用的方法是,您必须检测mousedown事件,记录其x,y位置(任何相关的位置),然后检测mouseup事件,并减去两个值。

我也合并了一些答案,主要是第一个和第二个与类,下面是我的版本:

export default class Swipe {
    constructor(options) {
        this.xDown = null;
        this.yDown = null;

        this.options = options;

        this.handleTouchStart = this.handleTouchStart.bind(this);
        this.handleTouchMove = this.handleTouchMove.bind(this);

        document.addEventListener('touchstart', this.handleTouchStart, false);
        document.addEventListener('touchmove', this.handleTouchMove, false);

    }

    onLeft() {
        this.options.onLeft();
    }

    onRight() {
        this.options.onRight();
    }

    onUp() {
        this.options.onUp();
    }

    onDown() {
        this.options.onDown();
    }

    static getTouches(evt) {
        return evt.touches      // browser API

    }

    handleTouchStart(evt) {
        const firstTouch = Swipe.getTouches(evt)[0];
        this.xDown = firstTouch.clientX;
        this.yDown = firstTouch.clientY;
    }

    handleTouchMove(evt) {
        if ( ! this.xDown || ! this.yDown ) {
            return;
        }

        let xUp = evt.touches[0].clientX;
        let yUp = evt.touches[0].clientY;

        let xDiff = this.xDown - xUp;
        let yDiff = this.yDown - yUp;


        if ( Math.abs( xDiff ) > Math.abs( yDiff ) ) {/*most significant*/
            if ( xDiff > 0 && this.options.onLeft) {
                /* left swipe */
                this.onLeft();
            } else if (this.options.onRight) {
                /* right swipe */
                this.onRight();
            }
        } else {
            if ( yDiff > 0 && this.options.onUp) {
                /* up swipe */
                this.onUp();
            } else if (this.options.onDown){
                /* down swipe */
                this.onDown();
            }
        }

        /* reset values */
        this.xDown = null;
        this.yDown = null;
    }
}

之后可以这样使用:

let swiper = new Swipe({
                    onLeft() {
                        console.log('You swiped left.');
                    }
});

当你只想调用“onLeft”方法时,它有助于避免控制台错误。

如果你只需要滑动,你最好只使用你需要的部分。 这应该适用于任何触摸设备。

这是经过gzip压缩,缩小,babel等大约450字节。

我根据其他答案编写了下面的类,它使用移动百分比而不是像素,以及一个事件分派器模式来挂钩/取消挂钩。

像这样使用它:

const dispatcher = new SwipeEventDispatcher(myElement);
dispatcher.on('SWIPE_RIGHT', () => { console.log('I swiped right!') })

export class SwipeEventDispatcher { constructor(element, options = {}) { this.evtMap = { SWIPE_LEFT: [], SWIPE_UP: [], SWIPE_DOWN: [], SWIPE_RIGHT: [] }; this.xDown = null; this.yDown = null; this.element = element; this.options = Object.assign({ triggerPercent: 0.3 }, options); element.addEventListener('touchstart', evt => this.handleTouchStart(evt), false); element.addEventListener('touchend', evt => this.handleTouchEnd(evt), false); } on(evt, cb) { this.evtMap[evt].push(cb); } off(evt, lcb) { this.evtMap[evt] = this.evtMap[evt].filter(cb => cb !== lcb); } trigger(evt, data) { this.evtMap[evt].map(handler => handler(data)); } handleTouchStart(evt) { this.xDown = evt.touches[0].clientX; this.yDown = evt.touches[0].clientY; } handleTouchEnd(evt) { const deltaX = evt.changedTouches[0].clientX - this.xDown; const deltaY = evt.changedTouches[0].clientY - this.yDown; const distMoved = Math.abs(Math.abs(deltaX) > Math.abs(deltaY) ? deltaX : deltaY); const activePct = distMoved / this.element.offsetWidth; if (activePct > this.options.triggerPercent) { if (Math.abs(deltaX) > Math.abs(deltaY)) { deltaX < 0 ? this.trigger('SWIPE_LEFT') : this.trigger('SWIPE_RIGHT'); } else { deltaY > 0 ? this.trigger('SWIPE_UP') : this.trigger('SWIPE_DOWN'); } } } } export default SwipeEventDispatcher;

你可以监听touchstart和touchend事件,并根据事件数据计算方向和力(Codepen):

让start = null; 文档。addEventListener('touchstart', e => { const touch = e. changedtouchs[0]; Start = [touch.]clientX touch.clientY); }); 文档。addEventListener('touchend', e => { const touch = e. changedtouchs[0]; Const end = [touch.]clientX touch.clientY); document.body.innerText = " ${结束[0]-[0]开始},${结束[1]-[1]开始}'; }); 点击这里

或者你可以围绕同样的概念构建一个更符合人体工程学的API (Codepen):

const removeListener = addSwipeRightListener(document, (force, e) => {
  console.info('Swiped right with force: ' + force);
});
// removeListener()

// swipe.js const { addSwipeLeftListener, addSwipeRightListener, addSwipeUpListener, addSwipeDownListener, } = (function() { // <element, {listeners: [...], handleTouchstart, handleTouchend}> const elements = new WeakMap(); function readTouch(e) { const touch = e.changedTouches[0]; if (touch == undefined) { return null; } return [touch.clientX, touch.clientY]; } function addListener(element, cb) { let elementValues = elements.get(element); if (elementValues === undefined) { const listeners = new Set(); const handleTouchstart = e => { elementValues.start = readTouch(e); }; const handleTouchend = e => { const start = elementValues.start; if (start === null) { return; } const end = readTouch(e); for (const listener of listeners) { listener([end[0] - start[0], end[1] - start[1]], e); } }; element.addEventListener('touchstart', handleTouchstart); element.addEventListener('touchend', handleTouchend); elementValues = { start: null, listeners, handleTouchstart, handleTouchend, }; elements.set(element, elementValues); } elementValues.listeners.add(cb); return () => deleteListener(element, cb); } function deleteListener(element, cb) { const elementValues = elements.get(element); const listeners = elementValues.listeners; listeners.delete(cb); if (listeners.size === 0) { elements.delete(element); element.removeEventListener('touchstart', elementValues.handleTouchstart); element.removeEventListener('touchend', elementValues.handleTouchend); } } function addSwipeLeftListener(element, cb) { return addListener(element, (force, e) => { const [x, y] = force; if (x < 0 && -x > Math.abs(y)) { cb(x, e); } }); } function addSwipeRightListener(element, cb) { return addListener(element, (force, e) => { const [x, y] = force; if (x > 0 && x > Math.abs(y)) { cb(x, e); } }); } function addSwipeUpListener(element, cb) { return addListener(element, (force, e) => { const [x, y] = force; if (y < 0 && -y > Math.abs(x)) { cb(x, e); } }); } function addSwipeDownListener(element, cb) { return addListener(element, (force, e) => { const [x, y] = force; if (y > 0 && y > Math.abs(x)) { cb(x, e); } }); } return { addSwipeLeftListener, addSwipeRightListener, addSwipeUpListener, addSwipeDownListener, } })(); // app.js function print(direction, force) { document.querySelector('#direction').innerText = direction; document.querySelector('#data').innerText = force; } addSwipeLeftListener(document, (force, e) => { print('left', force); }); addSwipeRightListener(document, (force, e) => { print('right', force); }); addSwipeUpListener(document, (force, e) => { print('up', force); }); addSwipeDownListener(document, (force, e) => { print('down', force); }); <h1>Swipe <span id="direction"></span></h1> Force (px): <span id="data"></span>

我重做了@ruben-martinez的答案,使用来自@givanse的惊人的解决方案,使用自定义反应钩子处理滑动事件。

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

export default function useSwiper() {
  const [domRef, setDomRef] = useState<any>();

  const xDown: React.MutableRefObject<number | null> = useRef(null);
  const yDown: React.MutableRefObject<number | null> = useRef(null);

  useEffect(() => {
if (!domRef) return;

function getTouches(event: React.TouchEvent<HTMLDivElement>) {
  return event.touches;
}

function handleTouchStart(event: any) {
  const firstTouch = getTouches(event)[0];
  xDown.current = firstTouch.clientX;
  yDown.current = firstTouch.clientY;
}

function handleTouchMove(event: React.TouchEvent<HTMLDivElement>) {
  if (!xDown.current || !yDown.current) return;

  const firstTouch = getTouches(event)[0];
  const xUp = firstTouch.clientX;
  const yUp = firstTouch.clientY;

  const xDiff = xDown.current - xUp;
  const yDiff = yDown.current - yUp;

  if (Math.abs(xDiff) > Math.abs(yDiff)) {
    // handle horizontal swipes
    if (xDiff > 0) {
      // we swiped right
      console.log("right");
    } else {
      // we swiped left
      console.log("left");
    }
  } else {
    // handle vertical swipes
    if (yDiff > 0) {
      // we swiped down
      console.log("down");
    } else {
      // we swiped up
      console.log("up");
    }
  }
}

function handleTouchEnd(event: React.TouchEvent<HTMLDivElement>) {
  xDown.current = null;
  yDown.current = null;
}


  domRef.addEventListener("touchstart", handleTouchStart, false);
  domRef.addEventListener("touchmove", handleTouchMove, false);
  domRef.addEventListener("touchend", handleTouchEnd, false);

return () => {
    domRef.removeEventListener("touchstart", handleTouchStart, false);
    domRef.removeEventListener("touchmove", handleTouchMove, false);
    domRef.removeEventListener("touchend", handleTouchEnd, false);
};
  }, [domRef]);

  return (ref: any) => setDomRef(ref);
}

我在实现他的答案时遇到的主要挑战是不知道如何将swipe元素的ref绑定到自定义钩子中的ref。

基本上,所发生的是我们从自定义钩子返回一个函数。这个函数允许我们传入一个来自我们想要监听的滑动动作的元素的ref。自定义钩子接收到ref后,用元素的ref更新钩子状态,从而触发重新渲染,这样我们就有了实际的元素!

这种函数式的ref样式还允许我们对多个元素使用钩子。如下所示,我想使用它的项目列表,以启用滑动删除:)

import useSwiper from "./hooks/useSwipe";

const EntryCard = ({ entry, godMode, reload }: EntryProps) => {
const swiperRef = useSwiper();

const handleEntryClick =
(entry: Entry) => async (event: React.MouseEvent<HTMLDivElement>) => {
  if (!godMode) return;

  try {
    reload((state) => !state);
  } catch (err) {
    console.log("Error deleting entry: ", err);
  }
};

return (
  <div className="item" onClick={handleEntryClick(entry)} ref={swiperRef}>
    <div className="username">{entry.userName}</div>
    <div className="score">{entry.weekScore}</div>
  </div>
 );
};

PS:你可以把函数传递给钩子来接收滑动值。谢谢:)如果你喜欢,请投票:)