vue-router2 _remove error on unbind

[coedycode]

Hi, I've been trying to use this module on a Vue2 project that's using a vue component per page with vue-router2.

When a page that's using a touch event is left, this code is throwing an error:

        unbind: function (el) {
            //删除dom监听事件
            el.touch._remove();
            el.touch = null;
        }

error: TypeError: Cannot read property '_remove' of null

I'm guessing the dom element has already been removed by the page transition, before this unbind event is triggered.

[coedycode]

This change fixed the issue for me:

        unbind: function (el) {
            //删除dom监听事件
            if(el.touch !== null) {
                el.touch._remove();
            }
            el.touch = null;
        }