util.js

/**
 * Created by zouxuan on 4/26/17.
 */

(function (global) {
    'use strict';
    global.elem = function elem(name, attrs, children) {
        attrs = attrs || {};
        children = children || [];
        var e=document.createElement(name);
        Object.keys(attrs).forEach(function (key) {
            e.setAttribute(key,attrs[key]);
        });
        children.forEach(function (child) {
            if(typeof child==='string'){
                child=document.createTextNode(child);
            }
            e.appendChild(child);
        })
        return e;
    }
    if(document.body.matches){
        global.matches=function matches(elem, selector) {
            return elem.matches(selector);
        }
    } else if(document.body.mozMatchesSelector){
        global.matches = function matches(elem, selector){ return elem.mozMatchesSelector(selector); };
    }else if (document.body.webkitMatchesSelector){
        global.matches = function matches(elem, selector){ return elem.webkitMatchesSelector(selector); };
    }else if (document.body.msMatchesSelector){
        global.matches = function matches(elem, selector){ return elem.msMatchesSelector(selector); };
    }else if(document.body.oMatchesSelector){
        global.matches = function matches(elem, selector){ return elem.oMatchesSelector(selector); };
    }

    global.closest=function closest(elem, selector) {
        while(elem){
            if (matches(elem, selector)){ return elem };
            elem = elem.parentElement;
        }
        return null;
    };

    global.requestAnimationFrame = global.requestAnimationFrame || global.mozRequestAnimationFrame || global.msRequestAnimationFrame || global.webkitRequestAnimationFrame || function(fn){
            setTimeout(fn, 20);
        };
    
    global.trigger = function trigger(name, target){
        target.dispatchEvent(new CustomEvent(name, {bubbles: true, cancelable: false}));
    };

})(window);