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Class Ext.data.DataWriter

Package:Ext.data
Defined In:DataWriter.js
Class:DataWriter
Subclasses:JsonWriter, XmlWriter
Extends:Object

Ext.data.DataWriter facilitates create, update, and destroy actions between an Ext.data.Store and a server-side framework. A Writer enabled Store will automatically manage the Ajax requests to perform CRUD actions on a Store.

Ext.data.DataWriter is an abstract base class which is intended to be extended and should not be created directly. For existing implementations, see Ext.data.JsonWriter.

Creating a writer is simple:

var writer = new Ext.data.JsonWriter({
    encode: false   // <--- false causes data to be printed to jsonData config-property of Ext.Ajax#reqeust
});

Same old JsonReader as Ext-2.x:

var reader = new Ext.data.JsonReader({idProperty: 'id'}, [{name: 'first'}, {name: 'last'}, {name: 'email'}]);

The proxy for a writer enabled store can be configured with a simple url:

// Create a standard HttpProxy instance.
var proxy = new Ext.data.HttpProxy({
    url: 'app.php/users'    // <--- Supports "provides"-type urls, such as '/users.json', '/products.xml' (Hello Rails/Merb)
});

For finer grained control, the proxy may also be configured with an API:

// Maximum flexibility with the API-configuration
var proxy = new Ext.data.HttpProxy({
    api: {
        read    : 'app.php/users/read',
        create  : 'app.php/users/create',
        update  : 'app.php/users/update',
        destroy : {  // <--- Supports object-syntax as well
            url: 'app.php/users/destroy',
            method: "DELETE"
        }
    }
});

Pulling it all together into a Writer-enabled Store:

var store = new Ext.data.Store({
    proxy: proxy,
    reader: reader,
    writer: writer,
    autoLoad: true,
    autoSave: true  // -- Cell-level updates.
});

Initiating write-actions automatically, using the existing Ext2.0 Store/Record API:

var rec = store.getAt(0);
rec.set('email', 'foo@bar.com');  // <--- Immediately initiates an UPDATE action through configured proxy.

store.remove(rec);  // <---- Immediately initiates a DESTROY action through configured proxy.

For record/batch updates, use the Store-configuration autoSave:false

var store = new Ext.data.Store({
    proxy: proxy,
    reader: reader,
    writer: writer,
    autoLoad: true,
    autoSave: false  // -- disable cell-updates
});

var urec = store.getAt(0);
urec.set('email', 'foo@bar.com');

var drec = store.getAt(1);
store.remove(drec);

// Push the button!
store.save();

Config Options

Config OptionsDefined By
 createRecord : Function
Abstract method that should be implemented in all subclasses (e.g.: JsonWriter.createRecord)
DataWriter
 destroyRecord : Function
Abstract method that should be implemented in all subclasses (e.g.: JsonWriter.destroyRecord)
DataWriter
 updateRecord : Function
Abstract method that should be implemented in all subclasses (e.g.: JsonWriter.updateRecord
DataWriter

Public Properties

This class has no public properties.

Public Methods

MethodDefined By

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