Observable Direct
Package: | Ext |
Defined In: | Direct.js |
Class: | Direct |
Extends: | Observable |
Overview
Ext.Direct aims to streamline communication between the client and server by providing a single interface that reduces the amount of common code typically required to validate data and handle returned data packets (reading data, error conditions, etc).
The Ext.direct namespace includes several classes for a closer integration with the server-side. The Ext.data namespace also includes classes for working with Ext.data.Stores which are backed by data from an Ext.Direct method.
Specification
For additional information consult the Ext.Direct Specification.
Providers
Ext.Direct uses a provider architecture, where one or more providers are used to transport data to and from the server. There are several providers that exist in the core at the moment:
A provider does not need to be invoked directly, providers are added via Ext.Direct.add.
Router
Ext.Direct utilizes a "router" on the server to direct requests from the client to the appropriate server-side method. Because the Ext.Direct API is completely platform-agnostic, you could completely swap out a Java based server solution and replace it with one that uses C# without changing the client side JavaScript at all.
Server side events
Custom events from the server may be handled by the client by adding listeners, for example:
{"type":"event","name":"message","data":"Successfully polled at: 11:19:30 am"}
// add a handler for a 'message' event sent by the server
Ext.Direct.on('message', function(e){
out.append(String.format('<p><i>{0}</i></p>', e.data));
out.el.scrollTo('t', 100000, true);
});
Config Options | Defined By | |
---|---|---|
listeners : Object A config object containing one or more event handlers to be added to this
object during initialization. This should ... 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
| Observable |
Property | Defined By | |
---|---|---|
eventTypes : Object Each event type implements a getData() method. The default event types are:
<div class="mdetail-params">
event : Ext.... Each event type implements a getData() method. The default event types are:
| Direct | |
exceptions : Object Four types of possible exceptions which can occur:
<div class="mdetail-params">
Ext.Direct.exceptions.TRANSPORT : 'xh... Four types of possible exceptions which can occur:
| Direct |
Method | Defined By | |
---|---|---|
addEvents( Object|String o, string Optional. ) : void 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. Parameters:
| Observable | |
addListener( String eventName, Function handler, [Object scope], [Object options] ) : void Appends an event handler to this object. Appends an event handler to this object. Parameters:
| Observable | |
addProvider( Object/Array provider ) : void Adds an Ext.Direct Provider and creates the proxy or stub methods to execute server-side methods.
If the provider is ... Adds an Ext.Direct Provider and creates the proxy or stub methods to execute server-side methods.
If the provider is not already connected, it will auto-connect.
Parameters:
| Direct | |
enableBubble( String/Array events ) : void Enables events fired by this Observable to bubble up an owner hierarchy by calling
this.getBubbleTarget() if present.... Enables events fired by this Observable to bubble up an owner hierarchy by calling
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:
Parameters:
| Observable | |
fireEvent( String eventName, Object... args ) : Boolean Fires the specified event with the passed parameters (minus the event name).
An event may be set to bubble up an Obse... 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. Parameters:
| Observable | |
getProvider( String id ) : void Retrieve a provider by the
id specified when the provider is
added. Retrieve a provider by the
id specified when the provider is
added. Parameters:
| Direct | |
hasListener( String eventName ) : Boolean 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 Parameters:
| Observable | |
on( String eventName, Function handler, [Object scope], [Object options] ) : void Appends an event handler to this object (shorthand for addListener.) Appends an event handler to this object (shorthand for addListener.) Parameters:
| Observable | |
purgeListeners() : void Removes all listeners for this object Removes all listeners for this object Parameters:
| Observable | |
relayEvents( Object o, Array events ) : void 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. Parameters:
| Observable | |
removeListener( String eventName, Function handler, [Object scope] ) : void Removes an event handler. Removes an event handler. Parameters:
| Observable | |
resumeEvents() : void Resume firing events. (see suspendEvents)
If events were suspended using the queueSuspended parameter, then all
event... 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. Parameters:
| Observable | |
suspendEvents( Boolean queueSuspended ) : void Suspend the firing of all events. (see resumeEvents) Suspend the firing of all events. (see resumeEvents) Parameters:
| Observable | |
un( String eventName, Function handler, [Object scope] ) : void Removes an event handler (shorthand for removeListener.) Removes an event handler (shorthand for removeListener.) Parameters:
| Observable |
Event | Defined By | |
---|---|---|
event : ( event e, Ext.direct.Provider provider ) Fires after an event. Fires after an event. Listeners will be called with the following arguments:
| Direct | |
exception : ( event e ) Fires after an event exception. Fires after an event exception. Listeners will be called with the following arguments:
| Direct |