HEventResponder

Description

Automatic event responder. Defines what events HControl listens to and actions to be taken.

Event handler methods

Pre-defined event handler methods, extend these in your subclass.

focus Called when the component gets focus
blur Called when the component loses focus
mouseDown Called when the mouse button is pushed down
mouseUp Called when the mouse button is released
mouseWheel Called when the mouse wheel is used
startDrag Called when the mouse button is pressed (and item is draggable).
endDrag Called when the mouse button is released (and item is draggable).
drag Called when the mouse is moved and mouse button is down (and item is draggable).
drop Called when a draggable item is released on the droppable.
startHover Called when a draggable item is moved over the droppable.
endHover Called when a draggable item is moved out of the droppable.
keyDown Called when the user presses a key, and the control is active.
keyUp Called when the user releases a key, and the control is active.
textEnter Called when the user releases a key regardless if the control is active or not.
gainedActiveStatus Called when the component gets activated.
lostActiveStatus Called when the component gets deactivated.

Inherits from:

Implemented by:

Constructor Method

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

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

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

setTextEnter( flag )

Description

Registers or releases event listening for textEnter events depending on the value of the flag argument.

Returns

self (HEventResponder#)

gainedActiveStatus( lastActiveControl )

Description

Default gainedActiveStatus event responder method. Does nothing by default. Called when the component gains active status; both focused and clicked.

Parameters

lastActiveControl A reference to the control that was active before this control became active. Can be null if there was no active control.

mouseDown( x, y, isLeftButton )

Description

Default mouseDown event responder method. Does nothing by default.

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.
isLeftButton Boolean flag; false if the right(context) mouse button is pressed.

startDrag( x, y )

Description

Default startDrag event responder method. Sets internal flags by default. This is the preferred method to extend if you want to do something when a drag event starts. If you extend, remember to call this.base();

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.

drag( x, y )

Description

Default drag event responder method. Does nothing by default. This is the preferred method to extend while a drag method is ongoing. Called whenever the mouse cursor moves and a drag event has been started.

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.

setEnabled( flag )

Description

Enables the HControl instance, if the enabled flag is true, and disables it if enabled is false. A disabled HControl won't respond events. Component themes reflect the disabled state typically with a dimmer appearance.

Parameters

flag Boolean; true enables, false disables.

Returns

self (HEventResponder#)

setMouseMove( flag )

Description

Alternative flag setter for the mouseMove event type. If set to true, starts listening to mouseDown events when the component has focus.

Parameters

flag Set the mouseDown event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

setClickable( flag )

Description

Alternative flag setter for the click event type. If set to true, starts listening to click events when the component has focus.

Parameters

flag Set the click event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

setMouseWheel( flag )

Description

Alternative flag setter for the mouseWheel event type. If set to true, starts listening to mouseWheel events when the component has focus.

Parameters

flag Set the mouseWheel event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

setDraggable( flag )

Description

Registers or releases event listening for startDrag, drag and endDrag -events depending on the value of the flag argument.

Parameters

flag Set the startDrag, drag and endDrag event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

mouseMove( x, y )

Description

Default mouseMove event responder method. Does nothing by default. Called whenever the mouse cursor is moved regardless if the component is active or has focus.

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.

mouseWheel( delta )

Description

Default mouseWheel event responder method. Does nothing by default.

Parameters

delta Scrolling delta, the wheel angle change. If delta is positive, wheel was scrolled up. Otherwise, it was scrolled down.

setDoubleClick( flag )

Same as setDoubleClickable

doubleClick( x, y, isLeftButton )

Description

Default click event responder method. Does nothing by default.

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.
isLeftButton Boolean flag; false if the right(context) mouse button is pressed.

endHover( obj )

Description

Default endHover event responder method. Does nothing by default. Extend the endHover method, if you want to do something when this instance is no longer the target of another instance's drag event. Called when a dragged component instance is dragged away from the target instance.

Parameters

obj The dragged component object.

setKeyUp( flag )

Description

Registers or releases event listening for keyUp events depending on the value of the flag argument.

Parameters

flag Set the keyUp event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

focus( )

Description

Default focus event responder method. Does nothing by default. Called when the component gets focus.

mouseUp( x, y, isLeftButton )

Description

Default mouseDown event responder method. Does nothing by default.

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.
isLeftButton Boolean flag; false if the right(context) mouse button is pressed.

endDrag( x, y )

Description

Default endDrag event responder method. Sets internal flags by default. This is the preferred method to extend if you want to do something when a drag event ends. If you extend, remember to call this.base();

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.

startHover( obj )

Description

Default startHover event responder method. Does nothing by default. Extend the startHover method, if you want to do something when this instance is the target of another instance's drag event. Called when a dragged component instance is dragged over the target instance.

Parameters

obj The dragged component object.

textEnter( )

Description

Default textEnter event responder method. Does nothing by default. Extend the textEnter method, if you want to do something when a key is released regardless if the component is active, has focus or not.

Parameters

keycode The ascii key code of the key that was released.

setEvents( events )

Description

The event responder interface for HControl. Registers the events defined by boolean properties of the events object to the control instance. The event manager handles the event mapping and abstraction itself. NOTE startDrag vs mouseDown and endDrag vs mouseUp events conflict, if both are set simultaneously.

Parameters

events A { event: state } Object structure, sets events based on the keys and the flag. All states are Booleans (true or false). A true state means the event listening for the event is enabled and a false state means the event listening is disabled. See the Event Types below:

Event States

Event State Description
mouseMove The global mouseMove event state. The component receives this event regardless if it's focused or not. The event responder method for it is mouseMove and it receives the absolute x and y coordinates of the mouse pointer when the mouse cursor position changes. Can also be toggled separately by using the setMouseMove method.
textEnter The global textEnter event state. The component receives this event regardless if it's focused or not. The event responder method for it is textEnter and it receives a every time a key on the keyboard is pressed. Can also be toggled separately by using the setTextEnter method.
click The local click event state. The component receives this event only if it's focused. The event responder method for it is click and it receives the absolute x and y coordinates of the mouse pointer as well as which mouse button was used to trigger the event. Can also be toggled separately by using the setClickable method.
mouseDown The local mouseDown event state. The component receives this event only if it's focused. The event responder method for it is mouseDown and it receives the absolute x and y coordinates of the mouse pointer as well as which mouse button was used to trigger the event. Can also be toggled separately by using the setMouseDown method.
mouseUp The local mouseUp event state. The component receives this event only if it's focused. The event responder method for it is mouseUp and it receives the absolute x and y coordinates of the mouse pointer as well as which mouse button was used to trigger the event. Can also be toggled separately by using the setMouseUp method.
mouseWheel The local mouseWheel event state. The component receives this event only if it's focused. The event responder method for it is mouseWheel and it receives the delta of the amount of the mouse scroll wheel was rolled: a floating point number, larger or smaller than 0, depending on the direction the scroll wheel was rolled. Can also be toggled separately by using the setMouseWheel method.
draggable The local draggable event states. The component receives these events only if it's focused. The event responders methods are startDrag, drag and endDrag. The events receive the mouse cursor coordinates. Can also be toggled separately by using the setDraggable method.
droppable The local droppable event states. The component receives this event only if another component is dragged (hovered) or dropped with the area of this component as the target. The event responders method for it are hoverStart, drop and hoverEnd. Can also be toggled separately by using the setDroppable method.
keyDown The local keyDown event state. The component receives this event only if it's focused. The event responder method for it is keyDown and it receives the ascii key code whenever a keyboard key is pressed. Can also be toggled separately by using the setKeyDown method.
keyUp The local keyUp event state. The component receives this event only if it's focused. The event responder method for it is keyUp and it receives the ascii key code whenever a keyboard key is released. Can also be toggled separately by using the setKeyUp method.

Usage

HControl.new(
  [0,0,100,20],
  HApplication.nu()
).setEvents({
  mouseUp: true,
  mouseDown: true
});

Returns

self (HEventResponder#)

setMouseDown( flag )

Description

Registers or releases event listening for mouseDown events depending on the value of the flag argument.

Parameters

flag Set the mouseDown event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

keyDown( keycode )

Description

Default keyDown event responder method. Does nothing by default. Extend the keyDown method, if you want to do something when a key is pressed and the component is active.

Parameters

keycode The ascii key code of the key that was pressed.

setDoubleClickable( flag )

Description

Registers or releases event listening for doubleClick events depending on the value of the flag argument.

Parameters

flag Set the doubleClick event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

drop( obj )

Description

Default drop event responder method. Does nothing by default. Extend the drop method, if you want to do something when this instance is the target of another instance's endDrag event. Called when a dragged component instance is dropped on the target instance.

Parameters

obj The dragged component object.

blur( )

Description

Default blur event responder method. Does nothing by default. Called when the component loses focus.

setMouseUp( flag )

Description

Registers or releases event listening for mouseUp events depending on the value of the flag argument.

Parameters

flag Set the mouseUp event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

setClick( flag )

Same as setClickable

lostActiveStatus( newActiveControl )

Description

Default lostActiveStatus event responder method. Does nothing by default. Called when the component loses active status; another component was focused and clicked.

Parameters

newActiveControl A reference to the control that became the currently active control. Can be null if there is no active control.

click( x, y, isLeftButton )

Description

Default click event responder method. Does nothing by default.

Parameters

x The horizontal coordinate units (px) of the mouse cursor position.
y The vertical coordinate units (px) of the mouse cursor position.
isLeftButton Boolean flag; false if the right(context) mouse button is pressed.

keyUp( keycode )

Description

Default keyUp event responder method. Does nothing by default. Extend the keyUp method, if you want to do something when a key is released and the component is active.

Parameters

keycode The ascii key code of the key that was released.

invalidatePositionCache( )

Description

Forces retrieving this control's DOM element position directly rather than using the cached version when the position is needed by EVENT. Child controls are invalidated recursively by HView.

Returns

self (HEventResponder#)

setDroppable( flag )

Description

Registers or releases event listening for startHover, drop and endHover -events depending on the value of the flag argument.

Parameters

flag Set the startHover, drop and endHover event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

setKeyDown( flag )

Description

Registers or releases event listening for keyDown events depending on the value of the flag argument.

Parameters

flag Set the keyDown event listening on/off (true/false) for the component instance.

Returns

self (HEventResponder#)

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

defaultEvents = { }

Default event listeners.

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.