COMM.Queue

Description

COMM.Queue executes javascript blocks in a managed queue.

COMM.Queue is used by COMM.Transporter and JSLoader to continue javascript command execution after a XMLHttpRequest finishes.

COMM.Queue runs as a single instance, dan't try to reconstruct it.

Inherits from:

Implements:

Constructor Method

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

To create a new instance use COMM.Queue.nu( ) or new COMM.Queue( ).

constructor( )

The constructor takes no arguments and starts queue flushing automatically.

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

pause( )

Description

Pauses the queue.

Use to stop execution, if some data or code needs to be loaded that the rest of the queue depends on. Typically called before an XMLHttpRequest with the onSuccess event defined to call resume when the request is done.

pushEval( evalStr )

Like push, but uses the code block as a string to be passed on as an evaluated anonymous function.

resume( )

Description

Resumes queue flushing.

Use to resume execuption, when some depending code for the rest of the queue has been loaded. Typically on an XMLHttpRequest onSuccess event.

push( function, arguments )

Description

Adds an item to the end of the queue.

Use to make the given function with its optional arguments the last item to flush.

Parameters:

function An anonymous function. Contains the code to execute.

arguments Optional_ arguments to pass on to the function

unshiftEval( evalStr, arguments )

Like unshift, but uses the code block as a string to be passed on as an evaluated anonymous function.

flush( )

Description

Flushes the queue until stopped.

Iterates through the commandQueue and calls each function. Removes items from the queue after execution.

unshift( function, arguments )

Description

Adds an item to the beginning of the queue.

Use to make the given function with its optional arguments the next item to flush.

Parameters:

function An anonymous function. Contains the code to execute.

arguments Optional_ arguments to pass on to the function

onIdle( )

Checks periodically, if the queue needs flushing.

setValue( value )

Inherited from: HValueResponder

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 (COMM.Queue#)

valueDiffers( value )

Inherited from: HValueResponder

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 )

Inherited from: HValueResponder

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 (COMM.Queue#)

removeView( viewId )

Inherited from: HApplication

Description

Removes the view of the given viewId.

Call this if you need to remove a child view from its parent without destroying its view, making it in effect a view without parent. Useful, for example, for moving a view from one parent component to another when dragging a component to a droppable container.

Parameters

viewId The view ID.

destroyView( viewId )

Inherited from: HApplication

Description

Removes and destructs the view of the given viewId.

Call this if you need to remove a child view from its parent, destroying its child views recursively and removing all of the DOM elements too.

Parameters

viewId The view ID.

die( )

Inherited from: HApplication

Description

The destructor of the HApplication instance.

Stops this application and destroys all its views recursively.

addView( view )

Inherited from: HApplication

Description

Adds a view to the app, HView defines an indentical structure for subviews.

Called from inside the HView constructor and should be automatic for all components that accept the parent parameter, usually the second argument, after the HRect instance.

Parameters

view Usually self (COMM.Queue#) inside HView -derived components.

Returns

The view ID.

buildParents( viewId )

Inherited from: HApplication

Description

Used by addView to build a self.parents array of parent classes.

Parameters

viewId The target view's ID.

destroyAllViews( )

Inherited from: HApplication

Description

Destructs all views but doesn't destroy the HApplication instance.

Destroys all the views added to this application but doesn't destroy the application itself.

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

STRINGS = { ERR: 'COMM.Queue Error: ', JS_EXEC_FAIL: 'Failed to execute the Javascript function: ', REASON: ' Reason:' }

A Group of localizable strings; errors and warnings.

elemId = 0

Inherited from: HApplication

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.