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