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Ext.data.writer.Writer

Alternate names

Ext.data.DataWriter
Ext.data.Writer

Hierarchy

Ext.Base
Ext.data.writer.Writer

Subclasses

Files

Base Writer class used by most subclasses of Ext.data.proxy.Server. This class is responsible for taking a set of Ext.data.Operation objects and a Ext.data.Request object and modifying that request based on the Operations.

For example a Ext.data.writer.Json would format the Operations and their Ext.data.Model instances based on the config options passed to the JsonWriter's constructor.

Writers are not needed for any kind of local storage - whether via a Web Storage proxy (see localStorage and sessionStorage) or just in memory via a MemoryProxy.

Dates

Before sending dates to the server, they can be formatted using one of the Ext.Date formats. These formats can be specified both on the field and the writer itself. In terms of precedence, from highest to lowest:

Defined By

Config options

Ext.data.writer.Writer
view source
: String

This is used for each field of type date in the model to format the value before it is sent to the server.

This is used for each field of type date in the model to format the value before it is sent to the server.

Ext.data.writer.Writer
view source
: String
This property is used to read the key for each value that will be sent to the server. ...

This property is used to read the key for each value that will be sent to the server. For example:

Ext.define('Person', {
    extend: 'Ext.data.Model',
    fields: [{
        name: 'first',
        mapping: 'firstName'
    }, {
        name: 'last',
        mapping: 'lastName'
    }, {
        name: 'age'
    }]
});
new Ext.data.writer.Writer({
    writeAllFields: true,
    nameProperty: 'mapping'
});

// This will be sent to the server
{
    firstName: 'first name value',
    lastName: 'last name value',
    age: 1
}

If the value is not present, the field name will always be used.

Defaults to: 'name'

Ext.data.writer.Writer
view source
: Boolean
True to write all fields from the record to the server. ...

True to write all fields from the record to the server. If set to false it will only send the fields that were modified. Note that any fields that have Ext.data.Field.persist set to false will still be ignored.

Defaults to: true

Ext.data.writer.Writer
view source
: Boolean
By default, each record's id is always included in the output for non-phantom records since in most cases the id will...

By default, each record's id is always included in the output for non-phantom records since in most cases the id will be required on the server to process the record action. This is helpful since the id will normally not be modified, and so would not be sent to the server unless writeAllFields was explicitly enabled.

However, there are cases where it is not desirable for the record id to be passed in the data directly. For example, when using a RESTful API the record id would typically be appended to the url instead.

Defaults to: true

Properties

Defined By

Instance properties

...

Defaults to: 'Ext.Base'

...

Defaults to: {}

...

Defaults to: []

...

Defaults to: {}

...

Defaults to: true

Ext.data.writer.Writer
view source
: Booleanprivate
true in this class to identify an object as an instantiated Writer, or subclass thereof. ...

true in this class to identify an object as an instantiated Writer, or subclass thereof.

Defaults to: true

Get the reference to the current class from which this object was instantiated. ...

Get the reference to the current class from which this object was instantiated. Unlike statics, this.self is scope-dependent and it's meant to be used for dynamic inheritance. See statics for a detailed comparison

Ext.define('My.Cat', {
    statics: {
        speciesName: 'Cat' // My.Cat.speciesName = 'Cat'
    },

    constructor: function() {
        alert(this.self.speciesName); // dependent on 'this'
    },

    clone: function() {
        return new this.self();
    }
});


Ext.define('My.SnowLeopard', {
    extend: 'My.Cat',
    statics: {
        speciesName: 'Snow Leopard'         // My.SnowLeopard.speciesName = 'Snow Leopard'
    }
});

var cat = new My.Cat();                     // alerts 'Cat'
var snowLeopard = new My.SnowLeopard();     // alerts 'Snow Leopard'

var clone = snowLeopard.clone();
alert(Ext.getClassName(clone));             // alerts 'My.SnowLeopard'
Defined By

Static properties

...

Defaults to: []

Methods

Defined By

Instance methods

Ext.data.writer.Writer
view source
new( [config] ) : Ext.data.writer.Writer
Creates new Writer. ...

Creates new Writer.

Parameters

  • config : Object (optional)

    Config object.

Returns

( args ) : Objectdeprecatedprotected
Call the original method that was previously overridden with override Ext.define('My.Cat', { constructor: functi...

Call the original method that was previously overridden with override

Ext.define('My.Cat', {
    constructor: function() {
        alert("I'm a cat!");
    }
});

My.Cat.override({
    constructor: function() {
        alert("I'm going to be a cat!");

        this.callOverridden();

        alert("Meeeeoooowwww");
    }
});

var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
                          // alerts "I'm a cat!"
                          // alerts "Meeeeoooowwww"

This method has been deprecated

as of 4.1. Use callParent instead.

Parameters

  • args : Array/Arguments

    The arguments, either an array or the arguments object from the current method, for example: this.callOverridden(arguments)

Returns

  • Object

    Returns the result of calling the overridden method

Call the "parent" method of the current method. ...

Call the "parent" method of the current method. That is the method previously overridden by derivation or by an override (see Ext.define).

 Ext.define('My.Base', {
     constructor: function (x) {
         this.x = x;
     },

     statics: {
         method: function (x) {
             return x;
         }
     }
 });

 Ext.define('My.Derived', {
     extend: 'My.Base',

     constructor: function () {
         this.callParent([21]);
     }
 });

 var obj = new My.Derived();

 alert(obj.x);  // alerts 21

This can be used with an override as follows:

 Ext.define('My.DerivedOverride', {
     override: 'My.Derived',

     constructor: function (x) {
         this.callParent([x*2]); // calls original My.Derived constructor
     }
 });

 var obj = new My.Derived();

 alert(obj.x);  // now alerts 42

This also works with static methods.

 Ext.define('My.Derived2', {
     extend: 'My.Base',

     statics: {
         method: function (x) {
             return this.callParent([x*2]); // calls My.Base.method
         }
     }
 });

 alert(My.Base.method(10);     // alerts 10
 alert(My.Derived2.method(10); // alerts 20

Lastly, it also works with overridden static methods.

 Ext.define('My.Derived2Override', {
     override: 'My.Derived2',

     statics: {
         method: function (x) {
             return this.callParent([x*2]); // calls My.Derived2.method
         }
     }
 });

 alert(My.Derived2.method(10); // now alerts 40

To override a method and replace it and also call the superclass method, use callSuper. This is often done to patch a method to fix a bug.

Parameters

  • args : Array/Arguments

    The arguments, either an array or the arguments object from the current method, for example: this.callParent(arguments)

Returns

  • Object

    Returns the result of calling the parent method

This method is used by an override to call the superclass method but bypass any overridden method. ...

This method is used by an override to call the superclass method but bypass any overridden method. This is often done to "patch" a method that contains a bug but for whatever reason cannot be fixed directly.

Consider:

 Ext.define('Ext.some.Class', {
     method: function () {
         console.log('Good');
     }
 });

 Ext.define('Ext.some.DerivedClass', {
     extend: 'Ext.some.Class',

     method: function () {
         console.log('Bad');

         // ... logic but with a bug ...

         this.callParent();
     }
 });

To patch the bug in Ext.some.DerivedClass.method, the typical solution is to create an override:

 Ext.define('App.patches.DerivedClass', {
     override: 'Ext.some.DerivedClass',

     method: function () {
         console.log('Fixed');

         // ... logic but with bug fixed ...

         this.callSuper();
     }
 });

The patch method cannot use callParent to call the superclass method since that would call the overridden method containing the bug. In other words, the above patch would only produce "Fixed" then "Good" in the console log, whereas, using callParent would produce "Fixed" then "Bad" then "Good".

Parameters

  • args : Array/Arguments

    The arguments, either an array or the arguments object from the current method, for example: this.callSuper(arguments)

Returns

  • Object

    Returns the result of calling the superclass method

...

Parameters

Returns the initial configuration passed to constructor when instantiating this class. ...

Returns the initial configuration passed to constructor when instantiating this class.

Parameters

  • name : String (optional)

    Name of the config option to return.

Returns

  • Object/Mixed

    The full config object or a single config value when name parameter specified.

Ext.data.writer.Writer
view source
( record, [operation] ) : Object
Formats the data for each record before sending it to the server. ...

Formats the data for each record before sending it to the server. This method should be overridden to format the data in a way that differs from the default.

Parameters

Returns

  • Object

    An object literal of name/value keys to be written to the server. By default this method returns the data property on the record.

Fires

    ...

    Parameters

    ( config ) : Ext.Basechainableprotected
    Initialize configuration for this class. ...

    Initialize configuration for this class. a typical example:

    Ext.define('My.awesome.Class', {
        // The default config
        config: {
            name: 'Awesome',
            isAwesome: true
        },
    
        constructor: function(config) {
            this.initConfig(config);
        }
    });
    
    var awesome = new My.awesome.Class({
        name: 'Super Awesome'
    });
    
    alert(awesome.getName()); // 'Super Awesome'
    

    Parameters

    Returns

    ( names, callback, scope )private
    ...

    Parameters

    ( config, applyIfNotSet ) : Ext.Basechainableprivate
    ...

    Parameters

    Returns

    Get the reference to the class from which this object was instantiated. ...

    Get the reference to the class from which this object was instantiated. Note that unlike self, this.statics() is scope-independent and it always returns the class from which it was called, regardless of what this points to during run-time

    Ext.define('My.Cat', {
        statics: {
            totalCreated: 0,
            speciesName: 'Cat' // My.Cat.speciesName = 'Cat'
        },
    
        constructor: function() {
            var statics = this.statics();
    
            alert(statics.speciesName);     // always equals to 'Cat' no matter what 'this' refers to
                                            // equivalent to: My.Cat.speciesName
    
            alert(this.self.speciesName);   // dependent on 'this'
    
            statics.totalCreated++;
        },
    
        clone: function() {
            var cloned = new this.self;                      // dependent on 'this'
    
            cloned.groupName = this.statics().speciesName;   // equivalent to: My.Cat.speciesName
    
            return cloned;
        }
    });
    
    
    Ext.define('My.SnowLeopard', {
        extend: 'My.Cat',
    
        statics: {
            speciesName: 'Snow Leopard'     // My.SnowLeopard.speciesName = 'Snow Leopard'
        },
    
        constructor: function() {
            this.callParent();
        }
    });
    
    var cat = new My.Cat();                 // alerts 'Cat', then alerts 'Cat'
    
    var snowLeopard = new My.SnowLeopard(); // alerts 'Cat', then alerts 'Snow Leopard'
    
    var clone = snowLeopard.clone();
    alert(Ext.getClassName(clone));         // alerts 'My.SnowLeopard'
    alert(clone.groupName);                 // alerts 'Cat'
    
    alert(My.Cat.totalCreated);             // alerts 3
    

    Returns

    Ext.data.writer.Writer
    view source
    ( request ) : Ext.data.Request
    Prepares a Proxy's Ext.data.Request object ...

    Prepares a Proxy's Ext.data.Request object

    Parameters

    Returns

    Fires

      Ext.data.writer.Writer
      view source
      ( data, field, record )private
      ...

      Parameters

      Defined By

      Static methods

      ( config )privatestatic
      ...

      Parameters

      ( members )chainableprivatestatic
      ...

      Parameters

      ( name, member )chainableprivatestatic
      ...

      Parameters

      ( members )chainablestatic
      Add methods / properties to the prototype of this class. ...

      Add methods / properties to the prototype of this class.

      Ext.define('My.awesome.Cat', {
          constructor: function() {
              ...
          }
      });
      
       My.awesome.Cat.addMembers({
           meow: function() {
              alert('Meowww...');
           }
       });
      
       var kitty = new My.awesome.Cat;
       kitty.meow();
      

      Parameters

      ( members ) : Ext.Basechainablestatic
      Add / override static properties of this class. ...

      Add / override static properties of this class.

      Ext.define('My.cool.Class', {
          ...
      });
      
      My.cool.Class.addStatics({
          someProperty: 'someValue',      // My.cool.Class.someProperty = 'someValue'
          method1: function() { ... },    // My.cool.Class.method1 = function() { ... };
          method2: function() { ... }     // My.cool.Class.method2 = function() { ... };
      });
      

      Parameters

      Returns

      ( xtype )chainableprivatestatic
      ...

      Parameters

      ( fromClass, members ) : Ext.Basechainableprivatestatic
      Borrow another class' members to the prototype of this class. ...

      Borrow another class' members to the prototype of this class.

      Ext.define('Bank', {
          money: '$$$',
          printMoney: function() {
              alert('$$$$$$$');
          }
      });
      
      Ext.define('Thief', {
          ...
      });
      
      Thief.borrow(Bank, ['money', 'printMoney']);
      
      var steve = new Thief();
      
      alert(steve.money); // alerts '$$$'
      steve.printMoney(); // alerts '$$$$$$$'
      

      Parameters

      • fromClass : Ext.Base

        The class to borrow members from

      • members : Array/String

        The names of the members to borrow

      Returns

      Create a new instance of this Class. ...

      Create a new instance of this Class.

      Ext.define('My.cool.Class', {
          ...
      });
      
      My.cool.Class.create({
          someConfig: true
      });
      

      All parameters are passed to the constructor of the class.

      Returns

      Overrides: Ext.layout.Layout.create

      ( alias, origin )static
      Create aliases for existing prototype methods. ...

      Create aliases for existing prototype methods. Example:

      Ext.define('My.cool.Class', {
          method1: function() { ... },
          method2: function() { ... }
      });
      
      var test = new My.cool.Class();
      
      My.cool.Class.createAlias({
          method3: 'method1',
          method4: 'method2'
      });
      
      test.method3(); // test.method1()
      
      My.cool.Class.createAlias('method5', 'method3');
      
      test.method5(); // test.method3() -> test.method1()
      

      Parameters

      ( config )privatestatic
      ...

      Parameters

      Get the current class' name in string format. ...

      Get the current class' name in string format.

      Ext.define('My.cool.Class', {
          constructor: function() {
              alert(this.self.getName()); // alerts 'My.cool.Class'
          }
      });
      
      My.cool.Class.getName(); // 'My.cool.Class'
      

      Returns

      ( )deprecatedstatic
      Adds members to class. ...

      Adds members to class.

      This method has been deprecated since 4.1

      Use addMembers instead.

      ( name, mixinClass )privatestatic
      Used internally by the mixins pre-processor ...

      Used internally by the mixins pre-processor

      Parameters

      ( fn, scope )chainableprivatestatic
      ...

      Parameters

      ( members ) : Ext.Basechainabledeprecatedstatic
      Override members of this class. ...

      Override members of this class. Overridden methods can be invoked via callParent.

      Ext.define('My.Cat', {
          constructor: function() {
              alert("I'm a cat!");
          }
      });
      
      My.Cat.override({
          constructor: function() {
              alert("I'm going to be a cat!");
      
              this.callParent(arguments);
      
              alert("Meeeeoooowwww");
          }
      });
      
      var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
                                // alerts "I'm a cat!"
                                // alerts "Meeeeoooowwww"
      

      As of 4.1, direct use of this method is deprecated. Use Ext.define instead:

      Ext.define('My.CatOverride', {
          override: 'My.Cat',
          constructor: function() {
              alert("I'm going to be a cat!");
      
              this.callParent(arguments);
      
              alert("Meeeeoooowwww");
          }
      });
      

      The above accomplishes the same result but can be managed by the Ext.Loader which can properly order the override and its target class and the build process can determine whether the override is needed based on the required state of the target class (My.Cat).

      This method has been deprecated since 4.1.0

      Use Ext.define instead

      Parameters

      • members : Object

        The properties to add to this class. This should be specified as an object literal containing one or more properties.

      Returns