mx.collections.ArrayList - Adobe® Flex® 4 Language Reference (Flex 4)

Package	mx.collections
Class	public class ArrayList
Inheritance	ArrayList EventDispatcher Object
Implements	IList, IExternalizable, IPropertyChangeNotifier
Subclasses	Conflicts

Language Version:

ActionScript 3.0

Product Version:

Flex 4

Runtime Versions:

Flash Player 10, AIR 1.5

The ArrayList class is a simple implementation of IList that uses a backing Array as the source of the data. Items in the backing Array can be accessed and manipulated using the methods and properties of the IList interface. Operations on an ArrayList instance modify the data source; for example, if you use the removeItemAt() method on an ArrayList, you remove the item from the underlying Array. This base class will not throw ItemPendingErrors but it is possible that a subclass might.

  <mx:ArrayList
  Properties
  source="null"
  />

Default MXML Propertysource

Public Properties

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	Property		Defined By
		constructor : Object A reference to the class object or constructor function for a given object instance.	Object
		length : int [read-only] Get the number of items in the list.	ArrayList
		prototype : Object [static] A reference to the prototype object of a class or function object.	Object
		source : Array The source array for this ArrayList.	ArrayList
		uid : String Provides access to the unique id for this list.	ArrayList

Public Methods

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	Method		Defined By
		ArrayList(source:Array = null) Construct a new ArrayList using the specified array as its source.	ArrayList
		addAll(addList:IList):void Adds a list of items to the current list, placing them at the end of the list in the order they are passed.	ArrayList
		addAllAt(addList:IList, index:int):void Adds a list of items to the current list, placing them at the position index passed in to the function.	ArrayList
		addEventListener(type:String, listener:Function, useCapture:Boolean = false, priority:int = 0, useWeakReference:Boolean = false):void Registers an event listener object with an EventDispatcher object so that the listener receives notification of an event.	EventDispatcher
		addItem(item:Object):void Add the specified item to the end of the list.	ArrayList
		addItemAt(item:Object, index:int):void Add the item at the specified index.	ArrayList
		dispatchEvent(event:Event):Boolean Dispatches an event into the event flow.	EventDispatcher
		getItemAt(index:int, prefetch:int = 0):Object Get the item at the specified index.	ArrayList
		getItemIndex(item:Object):int Return the index of the item if it is in the list such that getItemAt(index) == item.	ArrayList
		hasEventListener(type:String):Boolean Checks whether the EventDispatcher object has any listeners registered for a specific type of event.	EventDispatcher
		hasOwnProperty(name:String):Boolean Indicates whether an object has a specified property defined.	Object
		isPrototypeOf(theClass:Object):Boolean Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.	Object
		itemUpdated(item:Object, property:Object = null, oldValue:Object = null, newValue:Object = null):void Notify the view that an item has been updated.	ArrayList
		propertyIsEnumerable(name:String):Boolean Indicates whether the specified property exists and is enumerable.	Object
		removeAll():void Remove all items from the list.	ArrayList
		removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void Removes a listener from the EventDispatcher object.	EventDispatcher
		removeItem(item:Object):Boolean Removes the specified item from this list, should it exist.	ArrayList
		removeItemAt(index:int):Object Remove the item at the specified index and return it.	ArrayList
		setItemAt(item:Object, index:int):Object Place the item at the specified index.	ArrayList
		setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void Sets the availability of a dynamic property for loop operations.	Object
		toArray():Array Return an Array that is populated in the same order as the IList implementation.	ArrayList
		toLocaleString():String Returns the string representation of this object, formatted according to locale-specific conventions.	Object
		toString():String [override] Pretty prints the contents of this ArrayList to a string and returns it.	ArrayList
		valueOf():Object Returns the primitive value of the specified object.	Object
		willTrigger(type:String):Boolean Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.	EventDispatcher

Protected Methods

	Method		Defined By
		itemUpdateHandler(event:PropertyChangeEvent):void Called whenever any of the contained items in the list fire an ObjectChange event.	ArrayList
		startTrackUpdates(item:Object):void If the item is an IEventDispatcher watch it for updates.	ArrayList
		stopTrackUpdates(item:Object):void If the item is an IEventDispatcher stop watching it for updates.	ArrayList

Events

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	Summary	Defined By
activate	[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.	EventDispatcher
collectionChange	Dispatched when the IList has been updated in some way.	ArrayList
deactivate	[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.	EventDispatcher

Property Detail

length

property

length:int [read-only]

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Get the number of items in the list. An ArrayList should always know its length so it shouldn't return -1, though a subclass may override that behavior.

Implementation
public function get length():int

source

property

source:Array

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

The source array for this ArrayList. Any changes done through the IList interface will be reflected in the source array. If no source array was supplied the ArrayList will create one internally. Changes made directly to the underlying Array (e.g., calling theList.source.pop() will not cause CollectionEvents to be dispatched.

Implementation
public function get source():Array
public function set source(value:Array):void

uid

property

uid:String

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Provides access to the unique id for this list.

Implementation
public function get uid():String
public function set uid(value:String):void

Constructor Detail

ArrayList

()

Constructor

public function ArrayList(source:Array = null)

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Construct a new ArrayList using the specified array as its source. If no source is specified an empty array will be used.

Parameters

source:Array (default = null)

Method Detail

addAll

()

method

public function addAll(addList:IList):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Adds a list of items to the current list, placing them at the end of the list in the order they are passed.

Parameters

addList:IList — The list of items to add to the current list

addAllAt

()

method

public function addAllAt(addList:IList, index:int):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Adds a list of items to the current list, placing them at the position index passed in to the function. The items are placed at the index location and placed in the order they are recieved.

Parameters

	`addList:IList` — The list of items to add to the current list

	`index:int` — The location of the current list to place the new items.

addItem

()

method

public function addItem(item:Object):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Add the specified item to the end of the list. Equivalent to addItemAt(item, length);

Parameters

item:Object — the item to add

addItemAt

()

method

public function addItemAt(item:Object, index:int):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Add the item at the specified index. Any item that was after this index is moved out by one.

Parameters

	`item:Object` — the item to place at the index

	`index:int` — the index at which to place the item

Throws

RangeError — if index is less than 0 or greater than the length

getItemAt

()

method

public function getItemAt(index:int, prefetch:int = 0):Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Get the item at the specified index.

Parameters

	`index:int` — the index in the list from which to retrieve the item

	`prefetch:int` (default = `0`) — int indicating both the direction and amount of items to fetch during the request should the item not be local.

Returns

Object — the item at that index, null if there is none

Throws

	`Error` — if the data for that index needs to be loaded from a remote location

	`RangeError` — if the index < 0 or index >= length

getItemIndex

()

method

public function getItemIndex(item:Object):int

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Return the index of the item if it is in the list such that getItemAt(index) == item. Note that in this implementation the search is linear and is therefore O(n).

Parameters

item:Object — the item to find

Returns

int — the index of the item, -1 if the item is not in the list.

itemUpdated

()

method

public function itemUpdated(item:Object, property:Object = null, oldValue:Object = null, newValue:Object = null):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Notify the view that an item has been updated. This is useful if the contents of the view do not implement IEventDispatcher. If a property is specified the view may be able to optimize its notification mechanism. Otherwise it may choose to simply refresh the whole view.

Parameters

	`item:Object` — The item within the view that was updated.

	`property:Object` (default = `null`) — A String, QName, or int specifying the property that was updated.

	`oldValue:Object` (default = `null`) — The old value of that property. (If property was null, this can be the old value of the item.)

	`newValue:Object` (default = `null`) — The new value of that property. (If property was null, there's no need to specify this as the item is assumed to be the new value.)

itemUpdateHandler

()

method

protected function itemUpdateHandler(event:PropertyChangeEvent):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Called whenever any of the contained items in the list fire an ObjectChange event. Wraps it in a CollectionEventKind.UPDATE.

Parameters

event:PropertyChangeEvent

removeAll

()

method

public function removeAll():void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Remove all items from the list.

removeItem

()

method

public function removeItem(item:Object):Boolean

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Removes the specified item from this list, should it exist.

Parameters

item:Object — Object reference to the item that should be removed.

Returns

Boolean — Boolean indicating if the item was removed.

removeItemAt

()

method

public function removeItemAt(index:int):Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Remove the item at the specified index and return it. Any items that were after this index are now one index earlier.

Parameters

index:int — The index from which to remove the item.

Returns

Object — The item that was removed.

Throws

RangeError — if index < 0 or index >= length.

setItemAt

()

method

public function setItemAt(item:Object, index:int):Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Place the item at the specified index. If an item was already at that index the new item will replace it and it will be returned.

Parameters

	`item:Object` — the new value for the index

	`index:int` — the index at which to place the item

Returns

Object — the item that was replaced, null if none

Throws

RangeError — if index is less than 0 or greater than or equal to length

startTrackUpdates

()

method

protected function startTrackUpdates(item:Object):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

If the item is an IEventDispatcher watch it for updates. This is called by addItemAt and when the source is initially assigned.

Parameters

item:Object

stopTrackUpdates

()

method

protected function stopTrackUpdates(item:Object):void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

If the item is an IEventDispatcher stop watching it for updates. This is called by removeItemAt, removeAll, and before a new source is assigned.

Parameters

item:Object

toArray

()

method

public function toArray():Array

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Return an Array that is populated in the same order as the IList implementation.

Returns

Array

Throws

Error — if the data is not yet completely loaded from a remote location

toString

()

method

override public function toString():String

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Pretty prints the contents of this ArrayList to a string and returns it.

Returns

String

Event Detail

collectionChange

Event

Event Object Type: mx.events.CollectionEvent
property CollectionEvent.type = mx.events.CollectionEvent.COLLECTION_CHANGE

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Dispatched when the IList has been updated in some way.

The CollectionEvent.COLLECTION_CHANGE constant defines the value of the type property of the event object for an event that is dispatched when a collection has changed.

The properties of the event object have the following values. Not all properties are meaningful for all kinds of events. See the detailed property descriptions for more information.

Property	Value
`bubbles`	false
`cancelable`	false
`currentTarget`	The Object that defines the event listener that handles the event. For example, if you use `myButton.addEventListener()` to register an event listener, myButton is the value of the `currentTarget`.
`items`	An Array of objects with information about the items affected by the event. The contents of this field depend on the event kind; for details see the `items` property
`kind`	The kind of event. The valid values are defined in the CollectionEventKind class as constants.
`location`	Location within the target collection of the item(s) specified in the `items` property.
`oldLocation`	the previous location in the collection of the item specified in the `items` property.
`target`	The Object that dispatched the event; it is not always the Object listening for the event. Use the `currentTarget` property to always access the Object listening for the event.
`type`	CollectionEvent.COLLECTION_CHANGE