suppport ssr

Author: PanJiaChen

src/requestAnimationFrame.js

@@ -1,34 +1,38 @@
-let lastTime = 0;
-const prefixes = 'webkit moz ms o'.split(' '); // 各浏览器前缀
+let lastTime = 0
+const prefixes = 'webkit moz ms o'.split(' ') // 各浏览器前缀
+let requestAnimationFrame
+let cancelAnimationFrame
+let prefix
+const isServer = typeof window === 'undefined'
 
-let requestAnimationFrame = window.requestAnimationFrame;
-let cancelAnimationFrame = window.cancelAnimationFrame;
-
-let prefix;
-// 通过遍历各浏览器前缀，来得到requestAnimationFrame和cancelAnimationFrame在当前浏览器的实现形式
-for (let i = 0; i < prefixes.length; i++) {
-  if (requestAnimationFrame && cancelAnimationFrame) { break; }
-  prefix = prefixes[i];
-  requestAnimationFrame = requestAnimationFrame || window[prefix + 'RequestAnimationFrame'];
-  cancelAnimationFrame = cancelAnimationFrame || window[prefix + 'CancelAnimationFrame'] || window[prefix + 'CancelRequestAnimationFrame'];
+if (!isServer) {
+  requestAnimationFrame = window.requestAnimationFrame
+  cancelAnimationFrame = window.cancelAnimationFrame
+  // 通过遍历各浏览器前缀，来得到requestAnimationFrame和cancelAnimationFrame在当前浏览器的实现形式
+  for (let i = 0; i < prefixes.length; i++) {
+    if (requestAnimationFrame && cancelAnimationFrame) { break }
+    prefix = prefixes[i]
+    requestAnimationFrame = requestAnimationFrame || window[prefix + 'RequestAnimationFrame']
+    cancelAnimationFrame = cancelAnimationFrame || window[prefix + 'CancelAnimationFrame'] || window[prefix + 'CancelRequestAnimationFrame']
+  }
 }
 
 // 如果当前浏览器不支持requestAnimationFrame和cancelAnimationFrame，则会退到setTimeout
 if (!requestAnimationFrame || !cancelAnimationFrame) {
   requestAnimationFrame = function(callback) {
-	  const currTime = new Date().getTime();
-	  // 为了使setTimteout的尽可能的接近每秒60帧的效果
-	  const timeToCall = Math.max(0, 16 - (currTime - lastTime));
-	  const id = window.setTimeout(() => {
-    callback(currTime + timeToCall);
-	  }, timeToCall);
-	  lastTime = currTime + timeToCall;
-	  return id;
-  };
+    const currTime = new Date().getTime()
+    // 为了使setTimteout的尽可能的接近每秒60帧的效果
+    const timeToCall = Math.max(0, 16 - (currTime - lastTime))
+    const id = window.setTimeout(() => {
+      callback(currTime + timeToCall)
+    }, timeToCall)
+    lastTime = currTime + timeToCall
+    return id
+  }
 
   cancelAnimationFrame = function(id) {
-	  window.clearTimeout(id);
-  };
+    window.clearTimeout(id)
+  }
 }
 
 export { requestAnimationFrame, cancelAnimationFrame }