网易移动端适配

//网易移动端适配
;
(function(win, lib) {
var doc = win.document;
var docEl = doc.documentElement;
var metaEl = doc.querySelector('meta[name="viewport"]');
var flexibleEl = doc.querySelector('meta[name="flexible"]');
var dpr = 0;
var scale = 0;
var tid;
var flexible = lib.flexible || (lib.flexible = {});
if (metaEl) {
console.warn("将根据已有的meta标签来设置缩放比例");
var match = metaEl.getAttribute("content")
.match(/initial-scale=([d.]+)/);
if (match) {
scale = parseFloat(match[1]);
dpr = parseInt(1 / scale)
}
} else {
if (flexibleEl) {
var content = flexibleEl.getAttribute("content");
if (content) {
var initialDpr = content.match(/initial-dpr=([d.]+)/);
var maximumDpr = content.match(/maximum-dpr=([d.]+)/);
if (initialDpr) {
dpr = parseFloat(initialDpr[1]);
scale = parseFloat((1 / dpr)
.toFixed(2))
}
if (maximumDpr) {
dpr = parseFloat(maximumDpr[1]);
scale = parseFloat((1 / dpr)
.toFixed(2))
}
}
}
}
if (!dpr && !scale) {
var isAndroid = win.navigator.appVersion.match(/android/gi);
var isIPhone = win.navigator.appVersion.match(/iphone/gi);
var devicePixelRatio = win.devicePixelRatio;
if (isIPhone) {
if (devicePixelRatio >= 3 && (!dpr || dpr >= 3)) {
dpr = 3
} else {
if (devicePixelRatio >= 2 && (!dpr || dpr >= 2)) {
dpr = 2
} else {
dpr = 1
}
}
} else {
dpr = 1
}
scale = 1 / dpr
}
docEl.setAttribute("data-dpr", dpr);
if (!metaEl) {
metaEl = doc.createElement("meta");
metaEl.setAttribute("name", "viewport");
if (!!win.webPageScalable) {
metaEl.setAttribute("content", "initial-scale=" + scale + ", user-scalable=yes")
} else {
metaEl.setAttribute("content", "initial-scale=" + scale + ", maximum-scale=" + scale + ", minimum-scale=" + scale + ", user-scalable=no viewport-fit=cover")
}
if (docEl.firstElementChild) {
docEl.firstElementChild.appendChild(metaEl)
} else {
var wrap = doc.createElement("div");
wrap.appendChild(metaEl);
doc.write(wrap.innerHTML)
}
}

function refreshRem() {
var width = docEl.getBoundingClientRect()
.width;
var ua = navigator.userAgent.toLowerCase();
if (!/ipad.*yanxuan/.test(ua)) {
if (width / dpr > 750) {
width = 750 * dpr
}
}
var rem = width / 10;
docEl.style.fontSize = rem + "px";
flexible.rem = win.rem = rem
}
win.addEventListener("resize", function() {
clearTimeout(tid);
tid = setTimeout(refreshRem, 300)
}, false);
win.addEventListener("pageshow", function(e) {
if (e.persisted) {
clearTimeout(tid);
tid = setTimeout(refreshRem, 300)
}
}, false);
if (doc.readyState === "complete") {
doc.body.style.fontSize = 12 * dpr + "px"
} else {
doc.addEventListener("DOMContentLoaded", function(e) {
doc.body.style.fontSize = 12 * dpr + "px"
}, false)
}
refreshRem();
flexible.dpr = win.dpr = dpr;
flexible.refreshRem = refreshRem;
flexible.rem2px = function(d) {
var val = parseFloat(d) * this.rem;
if (typeof d === "string" && d.match(/rem$/)) {
val += "px"
}
return val
};
flexible.px2rem = function(d) {
var val = parseFloat(d) / this.rem;
if (typeof d === "string" && d.match(/px$/)) {
val += "rem"
}
return val
}
})(window, window["lib"] || (window["lib"] = {}));