Hierarchy
Ext.data.proxy.ProxyExt.data.proxy.ClientExt.data.proxy.WebStorageExt.data.proxy.LocalStorageMixins
The LocalStorageProxy uses the new HTML5 localStorage API to save 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 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 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.
True to batch actions of a particular type when synchronizing the store. Defaults to true.
True to batch actions of a particular type when synchronizing the store. Defaults to true.
Comma-separated ordering 'create', 'update' and 'destroy' actions when batching. Override this to set a different order for the batched CRUD actions to be executed in. Defaults to 'create,update,destroy'
The unique ID used as the key in which all record data are stored in the local storage object
The unique ID used as the key in which all record data are stored in the local storage object
(optional)
A config object containing one or more event handlers to be added to this object during initialization. This should be a valid listeners config object as specified in the addListener example for attaching multiple handlers at once.
DOM events from ExtJs Components
While some ExtJs Component classes export selected DOM events (e.g. "click", "mouseover" etc), this
is usually only done when extra value can be added. For example the DataView's
click event passing the node clicked on. To access DOM
events directly from a child element of a Component, we need to specify the element option to
identify the Component property to add a DOM listener to:
new Ext.panel.Panel({
width: 400,
height: 200,
dockedItems: [{
xtype: 'toolbar'
}],
listeners: {
click: {
element: 'el', //bind to the underlying el property on the panel
fn: function(){ console.log('click el'); }
},
dblclick: {
element: 'body', //bind to the underlying body property on the panel
fn: function(){ console.log('dblclick body'); }
}
}
});
Creates the proxy, throws an error if local storage is not supported in the current browser
Creates the proxy, throws an error if local storage is not supported in the current browser
Optional config object
Adds the specified events to the list of events which this Observable may fire.
Adds the specified events to the list of events which this Observable may fire.
Either an object with event names as properties with a value of true
or the first event name string if multiple event names are being passed as separate parameters.
[additional] Optional additional event names if multiple event names are being passed as separate parameters. Usage:
this.addEvents('storeloaded', 'storecleared');
Appends an event handler to this object.
Appends an event handler to this object.
The name of the event to listen for. May also be an object who's property names are event names. See
The method the event invokes.
(optional) The scope (this reference) in which the handler function is executed.
If omitted, defaults to the object which fired the event.
(optional) An object containing handler configuration. properties. This may contain any of the following properties:
this reference) in which the handler function is executed.
If omitted, defaults to the object which fired the event.This option is useful during Component construction to add DOM event listeners to elements of Components which will exist only after the Component is rendered. For example, to add a click listener to a Panel's body:
new Ext.panel.Panel({
title: 'The title',
listeners: {
click: this.handlePanelClick,
element: 'body'
}
});
When added in this way, the options available are the options applicable to Ext.core.Element.addListener
Combining Options
Using the options argument, it is possible to combine different types of listeners:
A delayed, one-time listener.
myPanel.on('hide', this.handleClick, this, {
single: true,
delay: 100
});
Attaching multiple handlers in 1 call
The method also allows for a single argument to be passed which is a config object containing properties
which specify multiple events. For example:
myGridPanel.on({
cellClick: this.onCellClick,
mouseover: this.onMouseOver,
mouseout: this.onMouseOut,
scope: this // Important. Ensure "this" is correct during handler execution
});
Adds listeners to any Observable object (or Element) which are automatically removed when this Component is destroyed.
Adds listeners to any Observable object (or Element) which are automatically removed when this Component is destroyed.
The item to which to add a listener/listeners.
The event name, or an object containing event name properties.
Optional. If the ename parameter was an event name, this
is the handler function.
Optional. If the ename parameter was an event name, this
is the scope (this reference) in which the handler function is executed.
Optional. If the ename parameter was an event name, this
is the addListener options.
Performs a batch of Operations, in the order specified by batchOrder. Used internally by Ext.data.Store's sync method. Example usage:
myProxy.batch({
create : [myModel1, myModel2],
update : [myModel3],
destroy: [myModel4, myModel5]
});
Where the myModel* above are Model instances - in this case 1 and 2 are new instances and have not been saved before, 3 has been saved previously but needs to be updated, and 4 and 5 have already been saved but should now be destroyed.
Object containing the Model instances to act upon, keyed by action name
Optional listeners object passed straight through to the Batch - see Ext.data.Batch
The newly created Ext.data.Batch object
Starts capture on the specified Observable. All events will be passed to the supplied function with the event name + standard signature of the event before the event is fired. If the supplied function returns false, the event will not fire.
The Observable to capture events from.
The function to call when an event is fired.
(optional) The scope (this reference) in which the function is executed. Defaults to the Observable firing the event.
Destroys all records stored in the proxy and removes all keys and values used to support the proxy from the storage object
Removes all listeners for this object including the managed listeners
Removes all listeners for this object including the managed listeners
Removes all managed listeners for this object.
Removes all managed listeners for this object.
Enables events fired by this Observable to bubble up an owner hierarchy by calling
this.getBubbleTarget() if present. There is no implementation in the Observable base class.
This is commonly used by Ext.Components to bubble events to owner Containers. See Ext.Component.getBubbleTarget. The default implementation in Ext.Component returns the Component's immediate owner. But if a known target is required, this can be overridden to access the required target more quickly.
Example:
Ext.override(Ext.form.field.Base, {
// Add functionality to Field's initComponent to enable the change event to bubble
initComponent : Ext.Function.createSequence(Ext.form.field.Base.prototype.initComponent, function() {
this.enableBubble('change');
}),
// We know that we want Field's events to bubble directly to the FormPanel.
getBubbleTarget : function() {
if (!this.formPanel) {
this.formPanel = this.findParentByType('form');
}
return this.formPanel;
}
});
var myForm = new Ext.formPanel({
title: 'User Details',
items: [{
...
}],
listeners: {
change: function() {
// Title goes red if form has been modified.
myForm.header.setStyle('color', 'red');
}
}
});
The event name to bubble, or an Array of event names.
Fires the specified event with the passed parameters (minus the event name).
An event may be set to bubble up an Observable parent hierarchy (See Ext.Component.getBubbleTarget) by calling enableBubble.
The name of the event to fire.
Variable number of parameters are passed to handlers.
returns false if any of the handlers return false otherwise it returns true.
Returns the model attached to this Proxy
Returns the model attached to this Proxy
The model
Returns the reader currently attached to this proxy instance
Returns the reader currently attached to this proxy instance
The Reader instance
Returns the writer currently attached to this proxy instance
Returns the writer currently attached to this proxy instance
The Writer instance
Checks to see if this object has any listeners for a specified event
Checks to see if this object has any listeners for a specified event
The name of the event to check for
True if the event is being listened for, else false
Sets observability on the passed class constructor.
This makes any event fired on any instance of the passed class also fire a single event through the class allowing for central handling of events on many instances at once.
Usage:
Ext.util.Observable.observe(Ext.data.Connection);
Ext.data.Connection.on('beforerequest', function(con, options) {
console.log('Ajax request made to ' + options.url);
});
The class constructor to make observable.
An object containing a series of listeners to add. See addListener.
Appends an event handler to this object (shorthand for addListener.)
Appends an event handler to this object (shorthand for addListener.)
The type of event to listen for
The method the event invokes
(optional) The scope (this reference) in which the handler function is executed.
If omitted, defaults to the object which fired the event.
(optional) An object containing handler configuration.
Relays selected events from the specified Observable as if the events were fired by this.
Relays selected events from the specified Observable as if the events were fired by this.
The Observable whose events this object is to relay.
Array of event names to relay.
Removes all added captures from the Observable.
Removes all added captures from the Observable.
The Observable to release
Removes an event handler.
Removes an event handler.
The type of event the handler was associated with.
The handler to remove. This must be a reference to the function passed into the addListener call.
(optional) The scope originally specified for the handler.
Removes listeners that were added by the mon method.
Removes listeners that were added by the mon method.
The item from which to remove a listener/listeners.
The event name, or an object containing event name properties.
Optional. If the ename parameter was an event name, this
is the handler function.
Optional. If the ename parameter was an event name, this
is the scope (this reference) in which the handler function is executed.
Resume firing events. (see suspendEvents)
If events were suspended using the queueSuspended parameter, then all
events fired during event suspension will be sent to any listeners now.
Sets the model associated with this proxy. This will only usually be called by a Store
Sets the model associated with this proxy. This will only usually be called by a Store
The new model. Can be either the model name string, or a reference to the model's constructor
Sets the new model on the associated Store, if one is present
Sets the Proxy's Reader by string, config object or Reader instance
Sets the Proxy's Reader by string, config object or Reader instance
The new Reader, which can be either a type string, a configuration object or an Ext.data.reader.Reader instance
The attached Reader object
Saves the given record in the Proxy. Runs each field's encode function (if present) to encode the data
Saves the given record in the Proxy. Runs each field's encode function (if present) to encode the data
The model instance
The id to save the record under (defaults to the value of the record's getId() function)
Sets the Proxy's Writer by string, config object or Writer instance
Sets the Proxy's Writer by string, config object or Writer instance
The new Writer, which can be either a type string, a configuration object or an Ext.data.writer.Writer instance
The attached Writer object
Suspend the firing of all events. (see resumeEvents)
Suspend the firing of all events. (see resumeEvents)
Pass as true to queue up suspended events to be fired after the resumeEvents call instead of discarding all suspended events;
Removes an event handler (shorthand for removeListener.)
Removes an event handler (shorthand for removeListener.)
The type of event the handler was associated with.
The handler to remove. This must be a reference to the function passed into the addListener call.
(optional) The scope originally specified for the handler.