StructureJS
0.15.2A class based utility library for building modular and scalable web platform applications. Features opt-in classes and utilities which provide a solid foundation and toolset to build your next project.
DisplayObjectContainer Class
The DisplayObjectContainer class is the base class for all objects that can be placed on the display list.
Index
Show:
Properties
Methods
- DisplayObjectContainer constructor
- addChild
- addChildAt
- addEventListener
- addEventListenerOnce
- contains
- create
- destroy
- disable
- dispatchEvent
- enable
- getChildAt
- getChildByCid
- getChildIndex
- getEventListeners
- getQualifiedClassName
- hasEventListener
- layout
- removeChild
- removeChildren
- removeEventListener
- swapChildren
- swapChildrenAt
Properties
_listeners
Any
protected
Holds a reference to added listeners.
alpha
Number
public
Indicates the alpha transparency value of the object specified.
children
Array.
A reference to the child DisplayObject instances to this parent object instance.
ctx
CanvasRenderingContext2D
public
The CanvasRenderingContext2D interface provides the 2D rendering context for the drawing surface of a canvas element. This property is only used with the canvas specific display objects.
height
Number
public
Indicates the height of the display object, in pixels.
Default: 0
isCreated
Boolean
public
The isCreated property is used to keep track if it is the first time this DisplayObject is created.
Default: false
isEnabled
Boolean
public
The isEnabled property is used to keep track of the enabled state of the object.
Default: false
mouseChildren
Boolean
public
Determines whether or not the children of the object are mouse enabled.
mouseEnabled
Boolean
public
Specifies whether this object receives mouse
name
String
public
Indicates the instance name of the DisplayObject.
numChildren
Int
public
Returns the number of children of this object.
Default: 0
parent
Any
public
Indicates the object that contains a child object. Uses the parent property to specify a relative path to display objects that are above the current display object in the display list hierarchy and helps facilitate event bubbling.
rotation
Number
public
Indicates the rotation of the DisplayObject instance, in degrees, from its original orientation.
scaleX
Number
public
Indicates the horizontal scale (percentage) of the object as applied from the registration point.
scaleY
Number
public
Indicates the vertical scale (percentage) of an object as applied from the registration point of the object.
sjsId
Int
public
The sjsId (StructureJS ID) is a unique identifier automatically assigned to most StructureJS objects upon instantiation.
Default: null
stage
Any
public
The Stage of the display object.
unscaledHeight
Number
public
A property providing access to the unscaledHeight.
Default: 100
unscaledWidth
Number
public
A property providing access to the unscaledWidth.
Default: 100
useHandCursor
Boolean
public
A Boolean value that indicates whether the pointing hand (hand cursor) appears when the pointer rolls over a display object.
visible
Boolean
public
Whether or not the display object is visible.
width
Number
public
Indicates the width of the display object, in pixels.
Default: 0
x
Number
public
A property providing access to the x position.
Default: 0
y
Number
public
A property providing access to the y position.
Default: 0
Methods
addChild
(
-
child
)
DisplayObjectContainer
public
chainable
-
child
Adds a child DisplayObject instance to this parent object instance. The child is added to the front (top) of all other children in this parent object instance. (To add a child to a specific index position, use the addChildAt() method.)
If you add a child object that already has a different parent, the object is removed from the child list of the other parent object.
Parameters:
-
childDisplayObjectThe DisplayObject instance to add as a child of this DisplayObjectContainer instance.
Returns:
DisplayObjectContainer:
Returns an instance of itself.
addChildAt
(
-
child
-
index
)
DisplayObjectContainer
public
chainable
-
child -
index
Adds a child DisplayObject instance to this DisplayObjectContainerContainer instance. The child is added at the index position specified. An index of 0 represents the back (bottom) of the display list for this DisplayObjectContainerContainer object.
Parameters:
-
childDisplayObjectThe DisplayObject instance to add as a child of this object instance.
-
indexIntThe index position to which the child is added. If you specify a currently occupied index position, the child object that exists at that position and all higher positions are moved up one position in the child list.
Returns:
DisplayObjectContainer:
Returns an instance of itself.
addEventListener
(
-
type
-
callback
-
scope
-
[priority=0]
)
public
chainable
-
type -
callback -
scope -
[priority=0]
Registers an event listener object with an EventDispatcher object so the listener receives notification of an event.
Parameters:
-
typeStringThe type of event.
-
callbackFunctionThe listener function that processes the event. This function must accept an Event object as its only parameter and must return nothing, as this example shows. @example function(event:Event):void
-
scopeAnyBinds the scope to a particular object (scope is basically what "this" refers to in your function). This can be very useful in JavaScript because scope isn't generally maintained.
-
[priority=0]Int optionalInfluences the order in which the listeners are called. Listeners with lower priorities are called after ones with higher priorities.
Example:
this.addEventListener(BaseEvent.CHANGE, this._handlerMethod, this);
_handlerMethod(event) {
console.log(event.target + " sent the event.");
console.log(event.type, event.data);
}addEventListenerOnce
(
-
type
-
callback
-
scope
-
[priority=0]
)
public
chainable
-
type -
callback -
scope -
[priority=0]
Registers an event listener object once with an EventDispatcher object so the listener will receive the notification of an event.
Parameters:
-
typeStringThe type of event.
-
callbackFunctionThe listener function that processes the event. This function must accept an Event object as its only parameter and must return nothing, as this example shows. @example function(event:Event):void
-
scopeAnyBinds the scope to a particular object (scope is basically what "this" refers to in your function). This can be very useful in JavaScript because scope isn't generally maintained.
-
[priority=0]Int optionalInfluences the order in which the listeners are called. Listeners with lower priorities are called after ones with higher priorities.
Example:
this.addEventListenerOnce(BaseEvent.CHANGE, this._handlerMethod, this);
_handlerMethod(event) {
console.log(event.target + " sent the event.");
console.log(event.type, event.data);
}contains
(
-
child
)
Boolean
public
-
child
Determines whether the specified display object is a child of the DisplayObject instance or the instance itself. The search includes the entire display list including this DisplayObject instance.
Parameters:
-
childDisplayObjectThe child object to test.
Returns:
Boolean:
true if the child object is a child of the DisplayObject or the container itself; otherwise false.
create
()
DisplayObject
public
chainable
The create function is intended to provide a consistent place for the creation or initializing the view. It will automatically be called the first time that the view is added to a DisplayObjectContainer. It is critical that all subclasses call the super for this function in their overridden methods.
Returns:
DisplayObject:
Returns an instance of itself.
destroy
()
Void
public
The purpose of the destroy method is to make an object ready for garbage collection. This should be thought of as a one way function. Once destroy is called no further methods should be called on the object or properties accessed. It is the responsibility of those who implement this function to stop all running Timers, all running Sounds, and take any other steps necessary to make an object eligible for garbage collection.
By default the destroy method will null out all properties of the class automatically. You should call destroy on other objects before calling the super.
Returns:
Void:
Example:
destroy() {
this.disable();
this._childInstance.destroy();
super.destroy();
}disable
()
public
chainable
The disable method is responsible for disabling event listeners and/or children of the containing objects.
Example:
disable() {
if (this.isEnabled === false) { return; }
this._childInstance.removeEventListener(BaseEvent.CHANGE, this.handlerMethod, this);
this._childInstance.disable();
super.disable();
}dispatchEvent
(
-
event
-
[data=null]
)
public
chainable
-
event -
[data=null]
Dispatches an event into the event flow. The event target is the EventDispatcher object upon which the dispatchEvent() method is called.
Parameters:
-
eventString | BaseEventThe Event object or event type string you want to dispatch. You can create custom events, the only requirement is all events must extend BaseEvent.
-
[data=null]Any optionalThe optional data you want to send with the event. Do not use this parameter if you are passing in a BaseEvent.
Example:
this.dispatchEvent('change');
// Example: Sending data with the event:
this.dispatchEvent('change', {some: 'data'});
// Example: With an event object
// (event type, bubbling set to true, cancelable set to true and passing data) :
let event = new BaseEvent(BaseEvent.CHANGE, true, true, {some: 'data'});
this.dispatchEvent(event);
// Here is a common inline event object being dispatched:
this.dispatchEvent(new BaseEvent(BaseEvent.CHANGE));enable
()
public
chainable
The enable method is responsible for enabling event listeners and/or children of the containing objects.
Example:
enable() {
if (this.isEnabled === true) { return; }
this._childInstance.addEventListener(BaseEvent.CHANGE, this.handlerMethod, this);
this._childInstance.enable();
super.enable();
}getChildAt
(
-
index
)
DisplayObject
-
index
Returns the child display object instance that exists at the specified index.
Parameters:
-
indexIntThe index position of the child object.
Returns:
DisplayObject:
The child display object at the specified index position.
getChildByCid
(
-
sjsId
)
DisplayObject | Null
public
-
sjsId
getChildIndex
(
-
child
)
Int
public
-
child
Returns the index position of a child DisplayObject instance.
Parameters:
-
childDisplayObjectThe DisplayObject instance to identify.
Returns:
Int:
The index position of the child display object to identify.
getEventListeners
()
Array
Returns and array of all current event types and there current listeners.
Returns:
Array
Example:
this.getEventListeners();getQualifiedClassName
()
String
public
Returns the fully qualified class name of an object.
Returns:
String:
Returns the class name.
Example:
let someClass = new SomeClass();
someClass.getQualifiedClassName();
// SomeClasshasEventListener
(
-
type
-
callback
-
scope
)
Boolean
public
-
type -
callback -
scope
layout
(
-
...rest
)
DisplayObject
public
chainable
-
...rest
The layout method provides a common function to handle updating objects in the view.
Parameters:
-
...restArray
Returns:
DisplayObject:
Returns an instance of itself.
print
()
String
public
Prints out each event listener in the console.log
Returns:
Example:
this.printEventListeners();
// [ClassName] is listening for the 'BaseEvent.change' event.
// [AnotherClassName] is listening for the 'BaseEvent.refresh' event.removeChild
(
-
child
)
DisplayObjectContainer
public
chainable
-
child
Removes the specified child object instance from the child list of the parent object instance. The parent property of the removed child is set to null , and the object is garbage collected if no other references to the child exist. The index positions of any objects above the child in the parent object are decreased by 1.
Parameters:
-
childDisplayObjectThe DisplayObject instance to remove.
Returns:
DisplayObjectContainer:
Returns an instance of itself.
removeChildren
()
DisplayObjectContainer
public
chainable
Removes all child DisplayObject instances from the child list of the DisplayObjectContainerContainer instance. The parent property of the removed children is set to null , and the objects are garbage collected if no other references to the children exist.
Returns:
DisplayObjectContainer:
Returns an instance of itself.
removeEventListener
(
-
type
-
callback
-
scope
)
public
chainable
-
type -
callback -
scope
swapChildren
(
-
child1
-
child2
)
DisplayObjectContainer
public
chainable
-
child1 -
child2
Swaps two DisplayObject's with each other.
Parameters:
-
child1DisplayObjectThe DisplayObject instance to be swap.
-
child2DisplayObjectThe DisplayObject instance to be swap.
Returns:
DisplayObjectContainer:
Returns an instance of itself.
swapChildrenAt
(
-
index1
-
index2
)
DisplayObjectContainer
public
chainable
-
index1 -
index2
Swaps child objects at the two specified index positions in the child list. All other child objects in the display object container remain in the same index positions.
Parameters:
-
index1IntThe index position of the first child object.
-
index2IntThe index position of the second child object.
Returns:
DisplayObjectContainer:
Returns an instance of itself.