快应用下模拟同步Stroage APi

快应用没有strorageXxxSync，它们需要一些巧妙的方法进行模拟。但即使这样，我们也需要你在打开每个页面上初始化一下这个方法。

ReactQuick.js中的实现

  1. const storage = require('@system.storage')
  2. import { noop } from 'react-core/util'
  4. function saveParse (str) {
  5.   try {
  6.     return JSON.parse(str)
  7.   } catch (err) {
  8.     // eslint-disable-line
  9.   }
  10.   return str
  11. }
  13. function setStorage ({ key, data, success, fail = noop, complete }) {
  14.   let value = data
  15.   if (typeof value === 'object') {
  16.     try {
  17.       value = JSON.stringify(value)
  18.     } catch (error) {
  19.       return fail(error)
  20.     }
  21.   }
  23.   storage.set({ key, value, success, fail, complete})
  24. }
  26. function getStorage ({ key, success, fail, complete }) {
  27.   function dataObj (data) {
  28.     success({
  29.       data: saveParse(data)
  30.     })
  31.   }
  32.   storage.get({ key, success: dataObj, fail, complete})
  33. }
  35. function removeStorage (obj) {
  36.   storage.delete(obj)
  37. }
  39. function clearStorage (obj) {
  40.   storage.clear(obj)
  41. }
  43. var initStorage = false
  44. export function initStorageSync (storageCache) {
  45.   if (typeof ReactQuick !== 'object') {
  46.     return
  47.   }
  48.   var apis = ReactQuick.api; // eslint-disable-line
  49.   var n = storage.length
  50.   var j = 0
  51.   for (var i = 0; i < n; i++) {
  52.     storage.key({
  53.       index: i,
  54.       success: function (key) {
  55.         storage.get({
  56.           key: key,
  57.           success: function (value) {
  58.             storageCache[key] = value
  59.             if (++j == n) {
  60.               console.log('init storage success')
  61.             }
  62.           }
  63.         })
  64.       }
  65.     })
  66.   }
  67.   apis.setStorageSync = function (key, value) {
  68.     setStorage({
  69.       key: key,
  70.       data: value
  71.     })
  72.     return storageCache[key] = value
  73.   }
  75.   apis.getStorageSync = function (key) {
  76.     return saveParse(storageCache[key])
  77.   }
  79.   apis.removeStorageSync = function (key) {
  80.     delete storageCache[key]
  81.     removeStorage({key: key})
  82.   }
  83.   apis.clearStorageSync = function () {
  84.     for (var i in storageCache) {
  85.       delete storageCache[i]
  86.     }
  87.     clearStorage({})
  88.   }
  89. }
  90. function warnToInitStorage () {
  91.   if (!initStorage) {
  92.     console.log('还没有初始化storageSync'); // eslint-disable-line
  93.   }
  94. }
  95. export var setStorageSync = warnToInitStorage
  96. export var getStorageSync = warnToInitStorage
  97. export var removeStorageSync = warnToInitStorage
  98. export var clearStorageSync = warnToInitStorage
  100. export { setStorage, getStorage, removeStorage, clearStorage }

app.js这样初始化它， 因为快应用是一个多页应用，不是SPA，只有globalData中的数据在每次页面打开时不会清空，globalData.__storage作为一个缓存可以加快我们读写的速度。

  1.     globalData = {
  2.         ufo: 'ufo'
  3.         __storage: {} 
  4.     };
  5.     onGlobalLoad() {
  6.         if (process.env.ANU_ENV === 'quick') {
  7.             React.api.initStorageSync(this.globalData.__storage);
  8.         }
  9.     }