Hammer.js无法删除事件监听器 [英] Hammer.js can't remove event listener

问题描述

我像这样创建锤子实例:

I create a hammer instance like so:

var el = document.getElementById("el");
var hammertime = Hammer(el);

然后我可以添加一个侦听器:

I can then add a listener:

hammertime.on("touch", function(e) {
    console.log(e.gesture);
}

但是，由于以下操作，我无法删除此侦听器:

However I can't remove this listener because the following does nothing:

hammertime.off("touch");

我做错了什么?我如何摆脱锤子听众?Hammer.js文档目前还很差，因此除了存在 .on()和 .off()方法的事实之外，它没有任何解释.我不能使用jQuery版本，因为这是对性能至关重要的应用程序.

What am I doing wrong? How do I get rid of a hammer listener? The hammer.js docs are pretty poor at the moment so it explains nothing beyond the fact that .on() and .off() methods exist. I can't use the jQuery version as this is a performance critical application.

JSFiddle展示了这一点: http://jsfiddle.net/LSrgh/1/

JSFiddle to showcase this: http://jsfiddle.net/LSrgh/1/

推荐答案

好，我知道了.来源很简单，它正在做:

Ok, I figured it out. The source it's simple enough, it's doing:

on: function(t, e) {
    for (var n = t.split(" "), i = 0; n.length > i; i++)
        this.element.addEventListener(n[i], e, !1);
    return this
},off: function(t, e) {
    for (var n = t.split(" "), i = 0; n.length > i; i++)
        this.element.removeEventListener(n[i], e, !1);
    return this
}

这里要注意的事情(除了错误的文档)，是 e 是 on 事件中的回调函数，所以您要做的是:

The thing to note here (apart from a bad documentation) it's that e it's the callback function in the on event, so you're doing:

this.element.addEventListener("touch", function() {
    //your function
}, !1);

但是，在删除操作中，您不会传递回调，而是这样做:

But, in the remove, you don't pass a callback so you do:

this.element.removeEventListener("touch", undefined, !1);

因此，浏览器不知道您是否要取消绑定巫婆功能，您可以不使用匿名函数来解决此问题，就像我在其中所做的那样:

So, the browser doesn't know witch function are you trying to unbind, you can fix this not using anonymous functions, like I did in:

小提琴

有关更多信息: JavaScript removeEventListener不起作用

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