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

Package	mx.collections
Class	public class GroupingCollection
Inheritance	GroupingCollection HierarchicalData EventDispatcher Object
Implements	IGroupingCollection

Deprecated Since 4.0: Please Use GroupingCollection2

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

The GroupingCollection class lets you create grouped data from flat data for display in the AdvancedDataGrid control. When you create the instance of the GroupingCollection from your flat data, you specify the field or fields of the data used to create the hierarchy.

To populate the AdvancedDataGrid control with grouped data, you create an instance of the GroupingCollection class from your flat data, and then pass that GroupingCollection instance to the data provider of the AdvancedDataGrid control. To specify the grouping fields of your flat data, you pass a Grouping instance to the GroupingCollection.grouping property. The Grouping instance contains an Array of GroupingField instances, one per grouping field.

The following example uses the GroupingCollection class to define two grouping fields: Region and Territory.

  <mx:AdvancedDataGrid id="myADG"    
    <mx:dataProvider> 
      <mx:GroupingCollection id="gc" source="{dpFlat}"> 
        <mx:grouping> 
          <mx:Grouping> 
            <mx:GroupingField name="Region"/> 
            <mx:GroupingField name="Territory"/> 
          </mx:Grouping> 
        </mx:grouping> 
      </mx:GroupingCollection> 
    </mx:dataProvider>  
     
    <mx:columns> 
      <mx:AdvancedDataGridColumn dataField="Region"/> 
      <mx:AdvancedDataGridColumn dataField="Territory"/> 
      <mx:AdvancedDataGridColumn dataField="Territory_Rep"/> 
      <mx:AdvancedDataGridColumn dataField="Actual"/> 
      <mx:AdvancedDataGridColumn dataField="Estimate"/> 
    </mx:columns> 
  </mx:AdvancedDataGrid>

MXML Syntax expanded

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The <mx.GroupingCollection> inherits all the tag attributes of its superclass, and defines the following tag attributes:

  <mx:GroupingCollection
  Properties 
    grouping="No default"
    source="No default"
    summaries="No default"
  />

This Class has been deprecated and replaced by a new Class GroupingCollection2 which provide faster, improved performance and a new summary calculation mechanism. Class SummaryField has also been deprecated and replaced by a new Class SummaryField2. Properties operation and summaryFunction are not present in the Class SummaryField2. A new property summaryOperation is introduced in SummaryField2.

Default MXML Propertygrouping

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
		grouping : Grouping Specifies the Grouping instance applied to the source data.	GroupingCollection
		prototype : Object [static] A reference to the prototype object of a class or function object.	Object
		source : Object [override] The source collection containing the flat data to be grouped.	GroupingCollection
		summaries : Array Array of SummaryRow instances that define any root-level data summaries.	GroupingCollection

Protected Properties

	Property		Defined By
		timer : flash.utils:Timer The timer which is associated with an asynchronous refresh operation.	GroupingCollection

Public Methods

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	Method		Defined By
		GroupingCollection() Constructor.	GroupingCollection
		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
		cancelRefresh():void If the refresh is performed asynchronously, cancels the refresh operation and stops the building of the groups.	GroupingCollection
		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 [override] Return super.source, if the grouping property is set, and an ICollectionView instance that refers to super.source if not.	GroupingCollection
		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
		refresh(async:Boolean = false):Boolean Applies the grouping to the view.	GroupingCollection
		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

Protected Methods

	Method		Defined By
		getParent(node:Object):* Returns the parent of a node.	GroupingCollection

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

grouping

property

grouping:Grouping

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Specifies the Grouping instance applied to the source data. Setting the grouping property does not automatically refresh the view, so you must call the refresh() method after setting this property.

Implementation
public function get grouping():Grouping
public function set grouping(value:Grouping):void

source

property

source:Object[override]

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

The source collection containing the flat data to be grouped. If the source is not a collection, it will be auto-wrapped into a collection.

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

summaries

property

public var summaries:Array

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Array of SummaryRow instances that define any root-level data summaries. Specify one or more SummaryRow instances to define the data summaries, as the following example shows:

      <mx:AdvancedDataGrid id="myADG" 
         width="100%" height="100%" 
         initialize="gc.refresh();">        
         <mx:dataProvider>
             <mx:GroupingCollection id="gc" source="{dpFlat}">
                 <mx:summaries>
                     <mx:SummaryRow summaryPlacement="last">
                         <mx:fields>
                             <mx:SummaryField dataField="Actual" 
                                 label="Min Actual" operation="MIN"/>
                             <mx:SummaryField dataField="Actual" 
                                 label="Max Actual" operation="MAX"/>
                         </mx:fields>
                       </mx:SummaryRow>
                     </mx:summaries>
                 <mx:Grouping>
                     <mx:GroupingField name="Region"/>
                     <mx:GroupingField name="Territory"/>
                 </mx:Grouping>
             </mx:GroupingCollection>
         </mx:dataProvider>        
         
         <mx:columns>
             <mx:AdvancedDataGridColumn dataField="Region"/>
             <mx:AdvancedDataGridColumn dataField="Territory_Rep"
                 headerText="Territory Rep"/>
             <mx:AdvancedDataGridColumn dataField="Actual"/>
             <mx:AdvancedDataGridColumn dataField="Estimate"/>
             <mx:AdvancedDataGridColumn dataField="Min Actual"/>
             <mx:AdvancedDataGridColumn dataField="Max Actual"/>
         </mx:columns>
      </mx:AdvancedDataGrid>

timer

property

protected var timer:flash.utils:Timer

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

The timer which is associated with an asynchronous refresh operation. You can use it to change the timing interval, pause the refresh, or perform other actions. The default value for the delay property of the Timer instance is 1, corresponding to 1 millisecond.

Constructor Detail

GroupingCollection

()

Constructor

public function GroupingCollection()

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Constructor.

Method Detail

cancelRefresh

()

method

public function cancelRefresh():void

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

If the refresh is performed asynchronously, cancels the refresh operation and stops the building of the groups. This method only cancels the refresh if it is initiated by a call to the refresh() method with an argument of true, corresponding to an asynchronous refresh.

getParent

()

method

protected function getParent(node:Object):*

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Returns the parent of a node. The parent of a top-level node is null.

Parameters

node:Object — The Object that defines the node.

Returns

* — The parent node containing the node as child, null for a top-level node, and undefined if the parent cannot be determined.

getRoot

()

method

override public function getRoot():Object

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Return super.source, if the grouping property is set, and an ICollectionView instance that refers to super.source if not.

Returns

Object — The object to return.

refresh

()

method

public function refresh(async:Boolean = false):Boolean

Language Version:

ActionScript 3.0

Product Version:

Flex 3

Runtime Versions:

Flash Player 9, AIR 1.1

Applies the grouping to the view. The IGroupingCollection does not detect changes to a group automatically, so you must call the refresh() method to update the view after setting the group property.

The refresh() method can be applied asynchronously by calling refresh(true).

When refresh() is called synchronously, a client should wait for a CollectionEvent event with the value of the kind property set to CollectionEventKind.REFRESH to ensure that the refresh() method completed.

Parameters

async:Boolean (default = false) — If true, defines the refresh to be asynchronous. By default it is false denoting synchronous refresh.

Returns

Boolean — true if the refresh() method completed, and false if the refresh is incomplete, which can mean that items are still pending.