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<pre class="prettyprint lang-js"><span id='Ext-data-proxy-LocalStorage'>/**
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</span> * @author Ed Spencer
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*
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* The LocalStorageProxy uses the new HTML5 localStorage API to save {@link Ext.data.Model Model} data locally on the
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* client browser. HTML5 localStorage is a key-value store (e.g. cannot save complex objects like JSON), so
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* LocalStorageProxy automatically serializes and deserializes data when saving and retrieving it.
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*
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* localStorage is extremely useful for saving user-specific information without needing to build server-side
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* infrastructure to support it. Let's imagine we're writing a Twitter search application and want to save the user's
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* searches locally so they can easily perform a saved search again later. We'd start by creating a Search model:
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*
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* Ext.define('Search', {
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* fields: ['id', 'query'],
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* extend: 'Ext.data.Model',
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* proxy: {
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* type: 'localstorage',
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* id : 'twitter-Searches'
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* }
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* });
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*
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* Our Search model contains just two fields - id and query - plus a Proxy definition. The only configuration we need to
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* pass to the LocalStorage proxy is an {@link #id}. This is important as it separates the Model data in this Proxy from
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* all others. The localStorage API puts all data into a single shared namespace, so by setting an id we enable
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* LocalStorageProxy to manage the saved Search data.
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*
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* Saving our data into localStorage is easy and would usually be done with a {@link Ext.data.Store Store}:
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*
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* //our Store automatically picks up the LocalStorageProxy defined on the Search model
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* var store = Ext.create('Ext.data.Store', {
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* model: "Search"
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* });
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*
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* //loads any existing Search data from localStorage
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* store.load();
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*
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* //now add some Searches
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* store.add({query: 'Sencha Touch'});
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* store.add({query: 'Ext JS'});
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*
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* //finally, save our Search data to localStorage
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* store.sync();
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*
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* The LocalStorageProxy automatically gives our new Searches an id when we call store.sync(). It encodes the Model data
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* and places it into localStorage. We can also save directly to localStorage, bypassing the Store altogether:
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*
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* var search = Ext.create('Search', {query: 'Sencha Animator'});
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*
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* //uses the configured LocalStorageProxy to save the new Search to localStorage
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* search.save();
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*
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* # Limitations
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*
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* If this proxy is used in a browser where local storage is not supported, the constructor will throw an error. A local
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* storage proxy requires a unique ID which is used as a key in which all record data are stored in the local storage
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* object.
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*
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* It's important to supply this unique ID as it cannot be reliably determined otherwise. If no id is provided but the
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* attached store has a storeId, the storeId will be used. If neither option is presented the proxy will throw an error.
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*/
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Ext.define('Ext.data.proxy.LocalStorage', {
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extend: 'Ext.data.proxy.WebStorage',
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alias: 'proxy.localstorage',
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alternateClassName: 'Ext.data.LocalStorageProxy',
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<span id='Ext-data-proxy-LocalStorage-method-getStorageObject'> //inherit docs
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</span> getStorageObject: function() {
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return window.localStorage;
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}
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});</pre>
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