HValueResponder

Description

Defines a minimal HValue responder interface. It's implemented by default by HControl.

Inherits from:

Extended by:

Implemented by:

Constructor Method

The constructor is invoked, when a new instance of HValueResponder is created.

To create a new instance use HValueResponder.nu( ) or new HValueResponder( ).

constructor( )

Inherited from: HClass

Protected instance method, gets called when a new instance is created.

Class Methods

implement( interface )

Inherited from: HClass

Description

Copies the members of interface to a HClass or a class inherited from HClass.

Usage:

Defines an interface: 
// Create an interface class that calculates the area
var AreaInterface = HClass.extend({
  constructor: null,
  area: function() {
    return this.getWidth() * this.getHeight();
  }
});



// Create a class that contains the coordinates of a rectangle.
var Rectangle = HClass.extend({
  constructor: function( x, y, width, height ) {
    this.x = x;
    this.y = y;
    this.width = width;
    this.height = height;
  },
  getWidth: function() {
    return this.width;
  },
  getHeight: function() {
    return this.height;
  }
});


// Makes the Rectangle class implement the AreaInterface
Rectangle.implement( AreaInterface );

nu( )

Inherited from: HClass

Class members:

Description

nu is a protected class method.

It does the same thing as the new keyword, but it is a class method.

Parameters:

Any parameters are passed on to the constructor method.

Usage:

Creates a class MyClass, then creates two instances of it: myClassInstance1 and myClassInstance2. The end result is the same. 
var MyClass = HClass.extend({
  name: 'Foo',
  constructor: function( param1, param2 ){
    var logMsg = [ 'param1:', param1,
                   'param2:', param2,
                   'name:', this.name ];
    console.log( logMsg.join(' ') );
  }
});

// Construction using the new keyword:
var myClassInstance1 = new MyClass( 'one', 'two' );

// Construction using the nu method:
var myClassInstance2 = MyClass.nu( 'one', 'two' );
However, when extending in place, the benefits of the nu method become obvious.

// Extending in place with the new keyword:
var myExtendedClassInstance1 = new (
  MyClass.extend({
    name: 'Bar'
  })
)( 'one', 'two' );

// The same as above, but using the nu method:
var myExtendedClassInstance2 = MyClass.extend({
  name: 'Bar'
}).nu( 'one', 'two' );

extend( instance, static )

Inherited from: HClass

Description

The class method used to extend a class.

If the member name constructor is defined as null instead of a function block in the instance object block, the class is defined as a singleton (single instance class).

Parameters:

instance The object that defines the class instance members.
static The object that defines the static class members.

Returns:

Returns the extended class object.

Usage:

var Point = HClass.extend({
  constructor: function( x, y ) {
    this.x = x;
    this.y = y;
  }
});
var Rectangle = Point.extend({
  // Instance members:
  constructor: function( x, y, width, height ) {
    this.base( x, y );
    this.width = width;
    this.height = height;
  },
  getWidth: function() {
    return this.width;
  },
  getHeight: function() {
    return this.height;
  }
},


// Class Members
{ description: "this is a Rectangle",
  getClass: function() {
    return this;
  }
});

Instance Methods

setValue( value )

Description

Assigns the object a new value. Extend it, if your component needs to do validation of the new value. For HControl instances, extend HControl#refreshValue to do something when the value has been set.

Parameter

value The new value. Allowed values depend on the component type and other usage of the bound HValue instance self.valueObj.

Returns

self (HValueResponder#)

valueDiffers( value )

Description

Checks, if the value given as parameter differs from value.

Parameters

value The value to be tested.

Returns

A boolean true (different) or false (same).

setValueObj( valueObj )

Description

Binds an HValue compatible instance to the component's valueObj. Also calls setValue. It should not be called from user code, instead use the HValue instance method bind.

Parameter

aValueObj The HValue instance object to bind.

Returns

self (HValueResponder#)

toString( )

Inherited from: HClass

Protected instance method, returns the instance represented as a String.

valueOf( )

Inherited from: HClass

Protected instance method, returns the value of an instance.

base( )

Inherited from: HClass

This method can be called from any other method to invoke that method's parent

Other Instance Members

prototype = { }

Inherited from: Object

Description

The prototype member of Object defines the instance members. These are copied to the instance object when the new keyword is called.