如何触发触摸事件？

Question

让我们开始与一些事件监听器：

window.addEventListener('scroll', function (e) { 
    console.log('scroll', e); 
}); 
window.addEventListener('touchstart', function (e) { 
    console.log('touchstart', e); 
}); 
window.addEventListener('touchmove', function (e) { 
    console.log('touchmove', e); 
}); 
window.addEventListener('touchend', function (e) { 
    console.log('touchend', e); 
}); 

我需要以编程触摸文档中{pageX: 0, pageY: 0}位置，将其移动到{pageX: 0, pageY: 100}并结束触摸事件。

为此，我要构建一个帮助函数TouchEvent，它将触发指定元素上的触摸事件。

/** 
* @see https://gist.github.com/sstephenson/448808 
* @see https://developer.apple.com/library/iad/documentation/UserExperience/Reference/TouchEventClassReference/TouchEvent/TouchEvent.html 
* @see http://stackoverflow.com/questions/18059860/manually-trigger-touch-event 
*/ 
function touchEvent (element, type, identifier, pageX, pageY) { 
    var e, 
     touch, 
     touches, 
     targetTouches, 
     changedTouches; 

    touch = document.createTouch(window, element, identifier, pageX, pageY, pageX, pageY); 

    if (type == 'touchend') { 
     touches = document.createTouchList(); 
     targetTouches = document.createTouchList(); 
     changedTouches = document.createTouchList(touch); 
    } else { 
     touches = document.createTouchList(touch); 
     targetTouches = document.createTouchList(touch); 
     changedTouches = document.createTouchList(touch); 
    } 

    e = document.createEvent('TouchEvent'); 
    e.initTouchEvent(type, true, true, window, null, 0, 0, 0, 0, false, false, false, false, touches, targetTouches, changedTouches, 1, 0); 

    window.dispatchEvent(e); 
}; 

我将确保文档被加载并发送代表先前商定的场景的触摸事件。

document.addEventListener('DOMContentLoaded', function() { 
    var identifier = new Date().getTime(), 
     element = document, 
     i = 0; 

    touchEvent(element, 'touchstart', identifier, 0, 0); 
    while (i++ < 100) { 
     touchEvent(element, 'touchmove', identifier, 0, i); 
    } 
    touchEvent(element, 'touchend', identifier, 0, i); 
}); 

预期的是，touchstart，touchmove和touchend事件被触发。意外的是，scroll事件没有被触发，并且文档的实际“触摸”未反映在当前文档中。

window.addEventListener('scroll', function (e) { 
 
    console.log('scroll', e); 
 
}); 
 
window.addEventListener('resize', function (e) { 
 
    console.log('resize', e); 
 
}); 
 
window.addEventListener('touchstart', function (e) { 
 
    console.log('touchstart', e); 
 
}); 
 
window.addEventListener('touchmove', function (e) { 
 
    console.log('touchmove', e); 
 
}); 
 
window.addEventListener('touchend', function (e) { 
 
    console.log('touchend', e); 
 
}); 
 

 
/** 
 
* @see https://gist.github.com/sstephenson/448808 
 
* @see https://developer.apple.com/library/iad/documentation/UserExperience/Reference/TouchEventClassReference/TouchEvent/TouchEvent.html 
 
* @see http://stackoverflow.com/questions/18059860/manually-trigger-touch-event 
 
*/ 
 
function touchEvent (element, type, identifier, pageX, pageY) { 
 
    var e, 
 
     touch, 
 
     touches, 
 
     targetTouches, 
 
     changedTouches; 
 
    
 
    if (!document.createTouch) { 
 
     throw new Error('This will work only in Safari browser.'); 
 
    } 
 

 
    touch = document.createTouch(window, element, identifier, pageX, pageY, pageX, pageY); 
 
    
 
    if (type == 'touchend') { 
 
     touches = document.createTouchList(); 
 
     targetTouches = document.createTouchList(); 
 
     changedTouches = document.createTouchList(touch); 
 
    } else { 
 
     touches = document.createTouchList(touch); 
 
     targetTouches = document.createTouchList(touch); 
 
     changedTouches = document.createTouchList(touch); 
 
    } 
 

 
    e = document.createEvent('TouchEvent'); 
 
    e.initTouchEvent(type, true, true, window, null, 0, 0, 0, 0, false, false, false, false, touches, targetTouches, changedTouches, 1, 0); 
 

 
    window.dispatchEvent(e); 
 
}; 
 

 
document.addEventListener('DOMContentLoaded', function() { 
 
    var identifier = new Date().getTime(), 
 
     element = document, 
 
     i = 0; 
 

 
    touchEvent(element, 'touchstart', identifier, 0, 0); 
 
    while (i++ < 100) { 
 
     touchEvent(element, 'touchmove', identifier, 0, i); 
 
    } 
 
    touchEvent(element, 'touchend', identifier, 0, i); 
 
});

#playground { 
 
    background: #999; height: 5000px; 
 
}

<div id="playground"></div>

什么是我的设置缺少让浏览器解释触摸事件，如果这些是由最终用户发出的？实质上，我希望浏览器能够响应一系列以编程方式触发的触摸开始，移动和结束事件进行滚动。

Answer 1

我不知道如果我理解正确你的问题，但是如果你开始在页面顶部的触摸和拖累你试图滚动到页面顶部，它已经存在何必滚动触发。也许从位置{pageX: 0, pageY: 100}开始，并在{pageX: 0, pageY: 0}结束，然后看看它是否仍然无法工作。

此致，KJ。