| Package | mx.effects | 
| Class | public class MaskEffect | 
| Inheritance | MaskEffect  Effect  EventDispatcher  Object | 
| Subclasses | Iris, WipeDown, WipeLeft, WipeRight, WipeUp | 
| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
A mask effect uses an overlay, called a mask, to perform the effect. By default, the mask is a rectangle with the same size as the target component.
The before or after state of the target component of a mask effect must be invisible. That means a mask effect always makes a target component appear on the screen, or disappear from the screen.
You use the scaleXFrom, scaleYFrom, 
  scaleXTo, and scaleX properties to specify 
  the initial and final scale of the mask, where a value of 1.0 corresponds
  to scaling the mask to the size of the target component, 2.0 scales 
  the mask to twice the size of the component, 0.5 scales the mask to half 
  the size of the component, and so on. 
  To use any one of these properties, you must specify all four.
You use the xFrom, yFrom, xTo, 
  and yTo properties to specify the coordinates of the initial
  position and final position of the mask relative to the target component, 
  where (0, 0) corresponds to the upper left corner of the target. 
  To use any one of these properties, you must specify all four.
The coordinates of the initial and final position of the mask
  depend on the type of effect and whether the show property
  is true or false.
  For example, for the WipeLeft effect with a show value of
  false, the coordinates of the initial mask position
  are (0, 0),corresponding to the upper-left corner of the target, 
  and the coordinates of the final position are the upper-right corner
  of the target (width, 0), where width is the width of the target.
For a show value of true for the WipeLeft
  effect, the coordinates of the initial mask position are (width, 0),
  and the coordinates of the final position are (0, 0).
 Hide MXML Syntax
Hide MXML SyntaxThe MaskEffect class defines the following properties, which all of its subclasses inherit:
  <mx:tagname
    createMaskFunction=""
    moveEasingFunction=""
    scaleEasingFunction=""
    scaleXFrom=""
    scaleXTo=""
    scaleYFrom=""
    scaleYTo=""
    show="true|false"
    xFrom=""
    xTo=""
    yFrom=""
    yTo=""
  />
  
More examples
Related API Elements
| Property | Defined By | ||
|---|---|---|---|
|  | className : String [read-only] 
      The name of the effect class, such as "Fade". | Effect | |
|  | constructor : Object 
	 A reference to the class object or constructor function for a given object instance. | Object | |
| createMaskFunction : Function 
      Function called when the effect creates the mask. | MaskEffect | ||
|  | customFilter : mx.effects:EffectTargetFilter 
      Specifies a custom filter object, of type EffectTargetFilter,
      used by the effect to determine the targets
      on which to play the effect. | Effect | |
|  | duration : Number  
      Duration of the effect in milliseconds. | Effect | |
|  | effectTargetHost : mx.effects:IEffectTargetHost 
      A property that lets you access the target list-based control
      of a data effect. | Effect | |
|  | filter : String 
      Specifies an algorithm for filtering targets for an effect. | Effect | |
|  | hideFocusRing : Boolean 
      Determines whether the effect should hide the focus ring
      when starting the effect. | Effect | |
|  | instanceClass : Class 
      An object of type Class that specifies the effect
      instance class class for this effect class. | Effect | |
|  | isPlaying : Boolean [read-only] 
      A read-only flag which is true if any instances of the effect
      are currently playing, and false if none are. | Effect | |
| moveEasingFunction : Function 
      Easing function to use for moving the mask. | MaskEffect | ||
|  | perElementOffset : Number 
      Additional delay, in milliseconds, for effect targets
      after the first target of the effect. | Effect | |
|  | playheadTime : Number 
      Current time position of the effect. | Effect | |
|  | relevantProperties : Array 
      An Array of property names to use when performing filtering. | Effect | |
|  | relevantStyles : Array 
      An Array of style names to use when performing filtering. | Effect | |
|  | repeatCount : int = 1 
      Number of times to repeat the effect. | Effect | |
|  | repeatDelay : int = 0 
      Amount of time, in milliseconds, to wait before repeating the effect. | Effect | |
| scaleEasingFunction : Function 
      Easing function to use for scaling the mask. | MaskEffect | ||
| scaleXFrom : Number 
      Initial scaleX for mask. | MaskEffect | ||
| scaleXTo : Number  
      Ending scaleX for mask. | MaskEffect | ||
| scaleYFrom : Number  
      Initial scaleY for mask. | MaskEffect | ||
| scaleYTo : Number 
      Ending scaleY for mask. | MaskEffect | ||
| showTarget : Boolean 
      Specifies that the target component is becoming visible, 
      true, or invisible, false. | MaskEffect | ||
|  | startDelay : int = 0 
      Amount of time, in milliseconds, to wait before starting the effect. | Effect | |
|  | suspendBackgroundProcessing : Boolean = false 
      If true, blocks all background processing
      while the effect is playing. | Effect | |
|  | target : Object  
      The object to which this effect is applied. | Effect | |
|  | targets : Array 
      An Array of objects that are targets for the effect. | Effect | |
|  | triggerEvent : Event 
      The Event object passed to this Effect 
      by the EffectManager when an effect is triggered,
      or null if the effect is not being
      played by the EffectManager. | Effect | |
| xFrom : Number  
      Initial position's x coordinate for mask. | MaskEffect | ||
| xTo : Number  
      Destination position's x coordinate for mask. | MaskEffect | ||
| yFrom : Number 
      Initial position's y coordinate for mask. | MaskEffect | ||
| yTo : Number  
      Destination position's y coordinate for mask. | MaskEffect | ||
| Property | Defined By | ||
|---|---|---|---|
|  | applyTransitionEndProperties : Boolean 
     This flag controls whether the effect, when run in a transition,
     automatically applies the property values according to the end
     state, as opposed to leaving values as set by the effect itself. | Effect | |
|  | endValuesCaptured : Boolean = false 
      A flag containing true if the end values
      of an effect have already been determined, 
      or false if they should be acquired from the
      current properties of the effect targets when the effect runs. | Effect | |
| Method | Defined By | ||
|---|---|---|---|
| MaskEffect(target:Object = null) 
      Constructor. | MaskEffect | ||
|  | 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 | |
|  | 
      Captures the current values of the relevant properties
      on the effect's targets and saves them as end values. | Effect | |
|  | 
      Captures the current values of the relevant properties
      of an additional set of targets
     
      Flex uses this function when a data change
      effect is run.
     
       | Effect | |
|  | 
      Captures the current values of the relevant properties
      on the effect's targets. | Effect | |
|  | 
      Creates a single effect instance and initializes it. | Effect | |
|  | 
      Takes an Array of target objects and invokes the 
      createInstance() method on each target. | Effect | |
|  | 
      Removes event listeners from an instance
      and removes it from the list of instances. | Effect | |
|  | 
	Dispatches an event into the event flow. | EventDispatcher | |
|  | 
      Interrupts an effect that is currently playing,
      and jumps immediately to the end of the effect. | Effect | |
| [override] 
      Returns the component properties modified by this effect. | MaskEffect | ||
|  | 
	Checks whether the EventDispatcher object has any listeners registered for a specific type 
	of event. | EventDispatcher | |
|  | 
	 Indicates whether an object has a specified property defined. | Object | |
|  | 
	 Indicates whether an instance of the Object class is in the prototype chain of the object specified 
	 as the parameter. | Object | |
|  | 
      Pauses the effect until you call the resume() method. | Effect | |
|  | 
      Begins playing the effect. | Effect | |
|  | 
	 Indicates whether the specified property exists and is enumerable. | Object | |
|  | 
	Removes a listener from the EventDispatcher object. | EventDispatcher | |
|  | 
      Resumes the effect after it has been paused 
      by a call to the pause() method. | Effect | |
|  | 
      Plays the effect in reverse, if the effect is currently playing,
      starting from the current position of the effect. | Effect | |
|  | 
     Sets the availability of a dynamic property for loop operations. | Object | |
|  | 
      Stops the effect, leaving the effect targets in their current state. | Effect | |
|  | 
	 Returns the string representation of this object, formatted according to locale-specific conventions. | Object | |
|  | 
	 Returns the string representation of the specified object. | Object | |
|  | 
	 Returns the primitive value of the specified object. | Object | |
|  | 
	Checks whether an event listener is registered with this EventDispatcher object or any of 
	its ancestors for the specified event type. | EventDispatcher | |
| Method | Defined By | ||
|---|---|---|---|
|  | 
      Used internally by the Effect infrastructure. | Effect | |
|  | 
      Called when an effect instance has finished playing. | Effect | |
|  | 
      This method is called when the effect instance starts playing. | Effect | |
|  | 
      Called when an effect instance has stopped by a call
      to the stop() method. | Effect | |
|  | 
      Determines the logic for filtering out an effect instance. | Effect | |
|  | 
      Called by the captureStartValues() method to get the value
      of a property from the target. | Effect | |
|  | 
      Copies properties of the effect to the effect instance. | Effect | |
| 
      Called when the TweenEffect dispatches a TweenEvent. | MaskEffect | ||
| Event | Summary | Defined By | ||
|---|---|---|---|---|
|  | [broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active. | EventDispatcher | ||
|  | [broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive. | EventDispatcher | ||
|  | Dispatched when one of the effect's instances finishes playing, either when the instance finishes playing or when the effect is interrupted by a call to the end() method. | Effect | ||
|  | Dispatched when the effect starts playing. | Effect | ||
|  | Dispatched when the effect has been stopped, which only occurs when the effect is interrupted by a call to the stop() method. | Effect | ||
| Dispatched when the effect ends. | MaskEffect | |||
| Dispatched when the effect starts, which corresponds to the first call to the onMoveTweenUpdate() and onScaleTweenUpdate() methods. | MaskEffect | |||
| Dispatched every time the effect updates the target. | MaskEffect | |||
| createMaskFunction | property | 
public var createMaskFunction:Function| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Function called when the effect creates the mask. The default value is a function that returns a Rectangle with the same dimensions as the target.
The custom mask function has the following signature:
      public function createLargeMask(targ:Object, bounds:Rectangle):Shape
      {
          var myMask:Shape = new FlexShape();
     
          // Create mask.
     
          return myMask;
      }
      
Your custom mask function takes an argument
      corresponding to the target component of the effect, 
      and a second argument that defines the dimensions of the 
      target so that you can correctly size the mask. 
      You use that argument to access properties of the target
      component, such as width and height,
      so that you can create a mask with the correct size.
The function returns a single Shape object that defines the mask.
| moveEasingFunction | property | 
public var moveEasingFunction:Function| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Easing function to use for moving the mask.
 The default value is null.
| scaleEasingFunction | property | 
public var scaleEasingFunction:Function| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Easing function to use for scaling the mask.
 The default value is null.
| scaleXFrom | property | 
public var scaleXFrom:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Initial scaleX for mask.
To specify this property,
      you must specify all four of these properties:
      scaleXFrom, scaleYFrom, 
      scaleXTo, and scaleX.
| scaleXTo | property | 
public var scaleXTo:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Ending scaleX for mask.
To specify this property,
      you must specify all four of these properties:
      scaleXFrom, scaleYFrom, 
      scaleXTo, and scaleX.
| scaleYFrom | property | 
public var scaleYFrom:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Initial scaleY for mask.
To specify this property,
      you must specify all four of these properties:
      scaleXFrom, scaleYFrom, 
      scaleXTo, and scaleX.
| scaleYTo | property | 
public var scaleYTo:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Ending scaleY for mask.
To specify this property,
      you must specify all four of these properties:
      scaleXFrom, scaleYFrom, 
      scaleXTo, and scaleX.
| showTarget | property | 
showTarget:Boolean| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
      Specifies that the target component is becoming visible, 
      true, or invisible, false. 
     
      If you specify this effect for a showEffect or 
      hideEffect trigger, Flex sets the 
      showTarget property for you, either to 
      true if the component becomes visible, 
      or false if the component becomes invisible. 
      If you use this effect with a different effect trigger, 
      you should set it yourself, often within the 
      event listener for the startEffect event.
     
      
 The default value is true.
Implementation
    public function get showTarget():Boolean    public function set showTarget(value:Boolean):void| xFrom | property | 
public var xFrom:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Initial position's x coordinate for mask.
To specify this property,
      you must specify all four of these properties:
      xFrom, yFrom, xTo, 
      and yTo. 
| xTo | property | 
public var xTo:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Destination position's x coordinate for mask.
To specify this property,
      you must specify all four of these properties:
      xFrom, yFrom, xTo, 
      and yTo. 
| yFrom | property | 
public var yFrom:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Initial position's y coordinate for mask.
To specify this property,
      you must specify all four of these properties:
      xFrom, yFrom, xTo, 
      and yTo. 
| yTo | property | 
public var yTo:Number| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Destination position's y coordinate for mask.
To specify this property,
      you must specify all four of these properties:
      xFrom, yFrom, xTo, 
      and yTo. 
| MaskEffect | () | Constructor | 
| getAffectedProperties | () | method | 
override public function getAffectedProperties():Array| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
      Returns the component properties modified by this effect. 
      This method returns an Array containing: 
      [ "visible", "width", "height" ].
      Since the WipeDown, WipeLeft, WipeRight, and WipeDown effect
      subclasses all modify these same  properties, those classes 
      do not implement this method. 
     
      
If you subclass the MaskEffect class to create a custom effect, and it modifies a different set of properties on the target, you must override this method and return an Array containing a list of the properties modified by your subclass.
Returns| Array— An Array of Strings specifying the names of the 
      properties modified by this effect. | 
Related API Elements
| tweenEventHandler | () | method | 
 protected function tweenEventHandler(event:mx.events:TweenEvent):void| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Called when the TweenEffect dispatches a TweenEvent. If you override this method, ensure that you call the super method.
Parameters
| event:mx.events:TweenEvent— An event object of type TweenEvent. | 
| tweenEnd | Event | 
mx.events.TweenEventproperty TweenEvent.type =
mx.events.TweenEvent.TWEEN_END| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
Dispatched when the effect ends.
When an effect plays a single time, this event occurs
  at the same time as an effectEnd event.
  If you configure the effect to repeat, 
  it occurs at the end of every repetition of the effect,
  and the endEffect event occurs
  after the effect plays for the final time.
TweenEvent.TWEEN_END constant defines the value of the 
	  event object's type property for a tweenEnd event. 
	 
	  The properties of the event object have the following values:
| 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 thecurrentTarget. | 
| target | The Object that dispatched the event; 
           it is not always the Object listening for the event. 
           Use the currentTargetproperty to always access the 
           Object listening for the event. | 
| value | The value passed to the onTweenEnd()method. | 
| tweenStart | Event | 
mx.events.TweenEventproperty TweenEvent.type =
mx.events.TweenEvent.TWEEN_START| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
  Dispatched when the effect starts, which corresponds to the 
  first call to the onMoveTweenUpdate() 
  and onScaleTweenUpdate() methods. 
  Flex also dispatches the first tweenUpdate event 
  for the effect at the same time.
 
  
The Effect.effectStart event is dispatched 
  before the tweenStart event.
TweenEvent.TWEEN_START constant defines the value of the 
	  event object's type property for a tweenStart event. 
	 
	  The properties of the event object have the following values:
| 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 thecurrentTarget. | 
| target | The Object that dispatched the event; 
           it is not always the Object listening for the event. 
           Use the currentTargetproperty to always access the 
           Object listening for the event. | 
| value | The value passed to the onTweenUpdate()method. | 
| tweenUpdate | Event | 
mx.events.TweenEventproperty TweenEvent.type =
mx.events.TweenEvent.TWEEN_UPDATE| Language Version: | ActionScript 3.0 | 
| Product Version: | Flex 3 | 
| Runtime Versions: | Flash Player 9, AIR 1.1 | 
  Dispatched every time the effect updates the target. 
  The dispatching of this event corresponds to the 
  calls to the onMoveTweenUpdate() 
  and onScaleTweenUpdate() methods.
 
  
TweenEvent.TWEEN_UPDATE constant defines the value of the 
	  event object's type property for a tweenUpdate event. 
	 
	  The properties of the event object have the following values:
| 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 thecurrentTarget. | 
| target | The Object that dispatched the event; 
           it is not always the Object listening for the event. 
           Use the currentTargetproperty to always access the 
           Object listening for the event. | 
| value | The value passed to the onTweenUpdate()method. | 
Thu Dec 4 2014, 05:50 PM -08:00
 Show MXML Syntax
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