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

Package	mx.collections
Class	public class HierarchicalData
Inheritance	HierarchicalData EventDispatcher Object
Implements	IHierarchicalData
Subclasses	GroupingCollection, GroupingCollection2

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Hierarchical data is data already in a structure of parent and child data items. The HierarchicalData class provides a default implementation for accessing and manipulating data for use in controls such as the AdvancedDataGrid control. To configure the AdvancedDataGrid control to display hierarchical data, you pass to the dataProvider property an instance of the HierarchicalData class. This implementation handles E4X, XML, and Object nodes in similar but different ways. See each method description for details on how the method accesses values in nodes of various types.

See also

mx.controls.AdvancedDataGrid

Public Properties

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	Property		Defined By
		childrenField : String Indicates the field name to be used to detect children objects in a data item.	HierarchicalData
		constructor : Object A reference to the class object or constructor function for a given object instance.	Object
		prototype : Object [static] A reference to the prototype object of a class or function object.	Object
		source : Object The source collection.	HierarchicalData

Public Methods

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	Method		Defined By
		HierarchicalData(value:Object = null) Constructor.	HierarchicalData
		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
		canHaveChildren(node:Object):Boolean Returns true if the node can contain children.	HierarchicalData
		dispatchEvent(event:Event):Boolean Dispatches an event into the event flow.	EventDispatcher
		getChildren(node:Object):Object Returns an Object representing the node's children.	HierarchicalData
		getData(node:Object):Object Returns data from a node.	HierarchicalData
		getRoot():Object Returns the root data item.	HierarchicalData
		hasChildren(node:Object):Boolean Returns true if the node has children.	HierarchicalData
		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
		propertyIsEnumerable(name:String):Boolean Indicates whether the specified property exists and is enumerable.	Object
		removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void Removes a listener from the EventDispatcher object.	EventDispatcher
		setPropertyIsEnumerable(name:String, isEnum:Boolean = true):void Sets the availability of a dynamic property for loop operations.	Object
		toLocaleString():String Returns the string representation of this object, formatted according to locale-specific conventions.	Object
		toString():String Returns the string representation of the specified object.	Object
		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

Events

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	Event		Summary	Defined By
		activate	[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.	EventDispatcher
		deactivate	[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.	EventDispatcher

Property Detail

childrenField

property

childrenField:String

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Indicates the field name to be used to detect children objects in a data item. By default, all subnodes are considered as children for XML data, and the children property is used for the Object data type. This is helpful in adapting to a data format that uses custom data fields to represent children.

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

source

property

source:Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

The source collection. The collection should implement the IList interface to facilitate operation like the addition and removal of items.

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

HierarchicalData

()

Constructor

public function HierarchicalData(value:Object = null)

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Constructor.

Parameters

value:Object (default = null) — The data used to populate the HierarchicalData instance.

Method Detail

canHaveChildren

()

method

public function canHaveChildren(node:Object):Boolean

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Returns true if the node can contain children.

Nodes do not have to contain children for the method to return true. This method is useful in determining whether other nodes can be appended as children to the specified node.

Parameters

node:Object — The Object that defines the node.

Returns

Boolean — true if the node can contain children.

getChildren

()

method

public function getChildren(node:Object):Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Returns an Object representing the node's children.

Parameters

node:Object — The Object that defines the node. If null, return a collection of top-level nodes.

Returns

Object — An Object containing the children nodes.

getData

()

method

public function getData(node:Object):Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Returns data from a node.

Parameters

node:Object — The node Object from which to get the data.

Returns

Object — The requested data.

getRoot

()

method

public function getRoot():Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Returns the root data item.

Returns

Object — The Object containing the root data item.

hasChildren

()

method

public function hasChildren(node:Object):Boolean

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Returns true if the node has children.

Parameters

node:Object — The Object that defines the node.

Returns

Boolean — true if the node has children.