Class Ext.data.ScriptTagProxy

Package:	Ext.data
Class:	ScriptTagProxy
Extends:	Object
Defined In:	ScriptTagProxy.js

An implementation of Ext.data.DataProxy that reads a data object from a URL which may be in a domain other than the originating domain of the running page.

Note that if you are retrieving data from a page that is in a domain that is NOT the same as the originating domain of the running page, you must use this class, rather than DataProxy.

The content passed back from a server resource requested by a ScriptTagProxy is executable JavaScript source code that is used as the source inside a <script> tag.

In order for the browser to process the returned data, the server must wrap the data object with a call to a callback function, the name of which is passed as a parameter by the ScriptTagProxy. Below is a Java example for a servlet which returns data for either a ScriptTagProxy, or an HttpProxy depending on whether the callback name was passed:


boolean scriptTag = false;
String cb = request.getParameter("callback");
if (cb != null) {
    scriptTag = true;
    response.setContentType("text/javascript");
} else {
    response.setContentType("application/x-json");
}
Writer out = response.getWriter();
if (scriptTag) {
    out.write(cb + "(");
}
out.print(dataBlock.toJsonString());
if (scriptTag) {
    out.write(");");
}

Properties - Methods - Events - Config Options

Public Properties

This class has no public properties.

Public Methods

Method		Defined By
	ScriptTagProxy( `Object config` )	ScriptTagProxy
		ScriptTagProxy
	abort() : void	ScriptTagProxy
	Abort the current server request.	ScriptTagProxy
	load( `Object params`, `Ext.data.DataReader reader`, `Function callback`, `Object scope`, `Object arg` ) : void	ScriptTagProxy
	Load data from the configured URL, read the data object into a block of Ext.data.Records using the passed Ext.data.Da...	ScriptTagProxy

Public Events

This class has no public events.

Config Options

Config Options		Defined By
	callbackParam : String	ScriptTagProxy
	(Optional) The name of the parameter to pass to the server which tells the server the name of the callback function s...	ScriptTagProxy
	nocache : Boolean	ScriptTagProxy
	(Optional) Defaults to true. Disable cacheing by adding a unique parameter name to the request.	ScriptTagProxy
	timeout : Number	ScriptTagProxy
	(Optional) The number of milliseconds to wait for a response. Defaults to 30 seconds.	ScriptTagProxy
	url : String	ScriptTagProxy
	The URL from which to request the data object.	ScriptTagProxy

Constructor Details

ScriptTagProxy

public function ScriptTagProxy( Object config )

Parameters:

config : Object
A configuration object.

Method Details

abort

public function abort()

Abort the current server request.

Parameters:

None.

Returns:

void

This method is defined by ScriptTagProxy.

load

public function load( Object params, Ext.data.DataReader reader, Function callback, Object scope, Object arg )

Load data from the configured URL, read the data object into a block of Ext.data.Records using the passed Ext.data.DataReader implementation, and process that block using the passed callback.

Parameters:

params : Object
An object containing properties which are to be used as HTTP parameters for the request to the remote server.
reader : Ext.data.DataReader
The Reader object which converts the data object into a block of Ext.data.Records.
callback : Function
The function into which to pass the block of Ext.data.Records. The function must be passed
- The Record block object
- The "arg" argument from the load function
- A boolean success indicator
scope : Object
The scope in which to call the callback
arg : Object
An optional argument which is passed to the callback as its second parameter.

Returns:

void

This method is defined by ScriptTagProxy.

Config Details

callbackParam

callbackParam : String

(Optional) The name of the parameter to pass to the server which tells the server the name of the callback function set up by the load call to process the returned data object. Defaults to "callback".

The server-side processing must read this parameter value, and generate javascript output which calls this named function passing the data object as its only parameter.

This config option is defined by ScriptTagProxy.

nocache

nocache : Boolean

(Optional) Defaults to true. Disable cacheing by adding a unique parameter name to the request.

This config option is defined by ScriptTagProxy.

timeout

timeout : Number

(Optional) The number of milliseconds to wait for a response. Defaults to 30 seconds.

This config option is defined by ScriptTagProxy.

url

url : String

The URL from which to request the data object.

This config option is defined by ScriptTagProxy.