add rem.js

plugins/rem.js

@@ -0,0 +1,54 @@
+(function (designWidth, maxWidth) {
+  var doc = document;
+  var win = window;
+  var docEl = doc.documentElement;
+  var tid;
+  var rootItem, rootStyle;
+
+  function refreshRem() {
+    var width = docEl.getBoundingClientRect().width;
+    if (!maxWidth) {
+      maxWidth = 540;
+    };
+    if (width > maxWidth) {
+      width = maxWidth;
+    }
+    //与淘宝做法不同，直接采用简单的rem换算方法1rem=100px
+    var rem = width * 100 / designWidth;
+    //兼容UC开始
+    rootStyle = "html{font-size:" + rem + 'px !important}';
+    rootItem = document.getElementById('rootsize') || document.createElement("style");
+    if (!document.getElementById('rootsize')) {
+      document.getElementsByTagName("head")[0].appendChild(rootItem);
+      rootItem.id = 'rootsize';
+    }
+    if (rootItem.styleSheet) {
+      rootItem.styleSheet.disabled || (rootItem.styleSheet.cssText = rootStyle)
+    } else {
+      try { rootItem.innerHTML = rootStyle } catch (f) { rootItem.innerText = rootStyle }
+    }
+    //兼容UC结束
+    docEl.style.fontSize = rem + "px";
+  };
+  refreshRem();
+
+  win.addEventListener("resize", function () {
+    clearTimeout(tid); //防止执行两次
+    tid = setTimeout(refreshRem, 300);
+  }, false);
+
+  win.addEventListener("pageshow", function (e) {
+    if (e.persisted) { // 浏览器后退的时候重新计算
+      clearTimeout(tid);
+      tid = setTimeout(refreshRem, 300);
+    }
+  }, false);
+
+  if (doc.readyState === "complete") {
+    doc.body.style.fontSize = "16px";
+  } else {
+    doc.addEventListener("DOMContentLoaded", function (e) {
+      doc.body.style.fontSize = "16px";
+    }, false);
+  }
+})(750, 750);