dvant/lib/utils/raf.js

A Vue.js 2.0 Mobile UI at dawnwin modified from Youzan

'use strict';

exports.__esModule = true;
exports.raf = raf;
exports.cancel = cancel;

var _index = require('./index');

var prev = Date.now();

/* istanbul ignore next */
/**
 * requestAnimationFrame polyfill
 */

function fallback(fn) {
  var curr = Date.now();
  var ms = Math.max(0, 16 - (curr - prev));
  var id = setTimeout(fn, ms);
  prev = curr + ms;
  return id;
}

/* istanbul ignore next */
var root = _index.isServer ? global : window;

/* istanbul ignore next */
var iRaf = root.requestAnimationFrame || root.webkitRequestAnimationFrame || fallback;

/* istanbul ignore next */
var iCancel = root.cancelAnimationFrame || root.webkitCancelAnimationFrame || root.clearTimeout;

function raf(fn) {
  return iRaf.call(root, fn);
}

function cancel(id) {
  iCancel.call(root, id);
}