Adobe® Flex® 4 Language Reference
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mx.effects 
Zoom 
Packagemx.effects
Classpublic class Zoom
InheritanceZoom Inheritance TweenEffect Inheritance Effect Inheritance EventDispatcher Inheritance Object

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1


Starting with Flex 4.0, Adobe recommends that you use the spark.effects.Scale class as an alternative to this class.

The Zoom effect zooms the object in or out on a center point.

When you apply a Zoom effect to text rendered using a system font, Flex scales the text between whole point sizes. While you do not have to use embedded fonts when you apply a Zoom effect to text, the Zoom will appear smoother when you apply it to embedded fonts.

Note: The Zoom effect does not work when the Container.autoLayout property is false.

MXML SyntaxexpandedHide MXML Syntax

The <mx:Zoom> tag inherits all of the tag attributes of its superclass, and adds the following tag attributes:

  <mx:Zoom
    id="ID"
    captureRollEvents="false|true"
    originX="Calculated"
    originY="Calculated"
    zoomWidthFrom="0.01"
    zoomWidthTo="1.0"
    zoomHeightFrom="0.01"
    zoomHeightTo="1.0"
  />
  

View the examples

See also



Public Properties
 PropertyDefined By
  captureRollEvents : Boolean
If true, prevents Flex from dispatching the rollOut and rollOver events if the mouse has not moved.
Zoom
 InheritedclassName : String
[read-only] The name of the effect class, such as "Fade".
Effect
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
 InheritedcustomFilter : 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
 Inheritedduration : Number
Duration of the effect in milliseconds.
Effect
 InheritedeasingFunction : Function = null
The easing function for the animation.
TweenEffect
 InheritedeffectTargetHost : mx.effects:IEffectTargetHost
A property that lets you access the target list-based control of a data effect.
Effect
 Inheritedfilter : String
Specifies an algorithm for filtering targets for an effect.
Effect
 InheritedhideFocusRing : Boolean
Determines whether the effect should hide the focus ring when starting the effect.
Effect
 InheritedinstanceClass : Class
An object of type Class that specifies the effect instance class class for this effect class.
Effect
 InheritedisPlaying : 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
  originX : Number
Number that represents the x-position of the zoom origin when the effect target is in a container that supports absolute positioning, such as the Canvas container.
Zoom
  originY : Number
Number that represents the y-position of the zoom origin when the effect target is in a container that supports absolute positioning, such as the Canvas container.
Zoom
 InheritedperElementOffset : Number
Additional delay, in milliseconds, for effect targets after the first target of the effect.
Effect
 InheritedplayheadTime : Number
Current time position of the effect.
Effect
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
 InheritedrelevantProperties : Array
An Array of property names to use when performing filtering.
Effect
 InheritedrelevantStyles : Array
An Array of style names to use when performing filtering.
Effect
 InheritedrepeatCount : int = 1
Number of times to repeat the effect.
Effect
 InheritedrepeatDelay : int = 0
Amount of time, in milliseconds, to wait before repeating the effect.
Effect
 InheritedstartDelay : int = 0
Amount of time, in milliseconds, to wait before starting the effect.
Effect
 InheritedsuspendBackgroundProcessing : Boolean = false
If true, blocks all background processing while the effect is playing.
Effect
 Inheritedtarget : Object
The object to which this effect is applied.
Effect
 Inheritedtargets : Array
An Array of objects that are targets for the effect.
Effect
 InheritedtriggerEvent : 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
  zoomHeightFrom : Number
Number that represents the scale at which to start the height zoom, as a percent between 0.01 and 1.0.
Zoom
  zoomHeightTo : Number
Number that represents the scale at which to complete the height zoom, as a percent between 0.01 and 1.0.
Zoom
  zoomWidthFrom : Number
Number that represents the scale at which to start the width zoom, as a percent between 0.01 and 1.0.
Zoom
  zoomWidthTo : Number
Number that represents the scale at which to complete the width zoom, as a percent between 0.01 and 1.0.
Zoom
Protected Properties
 PropertyDefined By
 InheritedapplyTransitionEndProperties : 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
 InheritedendValuesCaptured : 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
Public Methods
 MethodDefined By
  
Zoom(target:Object = null)
Constructor.
Zoom
 Inherited
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
 Inherited
Captures the current values of the relevant properties on the effect's targets and saves them as end values.
Effect
 Inherited
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
 Inherited
Captures the current values of the relevant properties on the effect's targets.
Effect
 Inherited
Creates a single effect instance and initializes it.
Effect
 Inherited
createInstances(targets:Array = null):Array
Takes an Array of target objects and invokes the createInstance() method on each target.
Effect
 Inherited
Removes event listeners from an instance and removes it from the list of instances.
Effect
 Inherited
Dispatches an event into the event flow.
EventDispatcher
 Inherited
end(effectInstance:IEffectInstance = null):void
Interrupts an effect that is currently playing, and jumps immediately to the end of the effect.
Effect
 Inherited
Returns an Array of Strings, where each String is the name of a property changed by this effect.
Effect
 Inherited
Checks whether the EventDispatcher object has any listeners registered for a specific type of event.
EventDispatcher
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Pauses the effect until you call the resume() method.
Effect
 Inherited
play(targets:Array = null, playReversedFromEnd:Boolean = false):Array
Begins playing the effect.
Effect
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
removeEventListener(type:String, listener:Function, useCapture:Boolean = false):void
Removes a listener from the EventDispatcher object.
EventDispatcher
 Inherited
Resumes the effect after it has been paused by a call to the pause() method.
Effect
 Inherited
Plays the effect in reverse, if the effect is currently playing, starting from the current position of the effect.
Effect
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Stops the effect, leaving the effect targets in their current state.
Effect
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
 Inherited
Returns the string representation of the specified object.
Object
 Inherited
Returns the primitive value of the specified object.
Object
 Inherited
Checks whether an event listener is registered with this EventDispatcher object or any of its ancestors for the specified event type.
EventDispatcher
Protected Methods
 MethodDefined By
 Inherited
applyValueToTarget(target:Object, property:String, value:*, props:Object):void
Used internally by the Effect infrastructure.
Effect
 Inherited
Called when an effect instance has finished playing.
Effect
 Inherited
This method is called when the effect instance starts playing.
Effect
 Inherited
Called when an effect instance has stopped by a call to the stop() method.
Effect
 Inherited
filterInstance(propChanges:Array, target:Object):Boolean
Determines the logic for filtering out an effect instance.
Effect
 Inherited
getValueFromTarget(target:Object, property:String):*
Called by the captureStartValues() method to get the value of a property from the target.
Effect
 Inherited
Copies properties of the effect to the effect instance.
Effect
 Inherited
Called when the TweenEffect dispatches a TweenEvent.
TweenEffect
Events
 Event Summary Defined By
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application gains operating system focus and becomes active.EventDispatcher
 Inherited[broadcast event] Dispatched when the Flash Player or AIR application operating loses system focus and is becoming inactive.EventDispatcher
 InheritedDispatched 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
 InheritedDispatched when the effect starts playing.Effect
 InheritedDispatched when the effect has been stopped, which only occurs when the effect is interrupted by a call to the stop() method.Effect
 InheritedDispatched when the tween effect ends.TweenEffect
 InheritedDispatched when the tween effect starts, which corresponds to the first call to the onTweenUpdate() method.TweenEffect
 InheritedDispatched every time the tween effect updates the target.TweenEffect
Property Detail

captureRollEvents

property
public var captureRollEvents:Boolean

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

If true, prevents Flex from dispatching the rollOut and rollOver events if the mouse has not moved. Set this property to true when you use the Zoom effect to toggle the effect target between a big and small size.

For example, you use the rollOverEffect to trigger the Zoom effect to reduce the size of the target. As the target shrinks, the mouse pointer is no longer over the target, triggering a rollOut event, and the corresponding rollOutEffect. By setting the captureRollEvents property to true, you prevent Flex from dispatching the rollOut event unless it occurs because you moved the mouse.

The default value is false.

originX

property 
public var originX:Number

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Number that represents the x-position of the zoom origin when the effect target is in a container that supports absolute positioning, such as the Canvas container. The zoom origin is the position on the target around which the Zoom effect is centered.

The value must be between 0 and the width of the target component.

The default value is target.width / 2, which is the center of the target.

originY

property 
public var originY:Number

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Number that represents the y-position of the zoom origin when the effect target is in a container that supports absolute positioning, such as the Canvas container. The zoom origin is the position on the target around which the Zoom effect is centered.

The value must be between 0 and the height of the target component.

The default value is target.height / 2, which is the center of the target.

zoomHeightFrom

property 
public var zoomHeightFrom:Number

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Number that represents the scale at which to start the height zoom, as a percent between 0.01 and 1.0. The default value is 0.01, which is very small.

zoomHeightTo

property 
public var zoomHeightTo:Number

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Number that represents the scale at which to complete the height zoom, as a percent between 0.01 and 1.0. The default value is 1.0, which is the object's normal size.

zoomWidthFrom

property 
public var zoomWidthFrom:Number

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Number that represents the scale at which to start the width zoom, as a percent between 0.01 and 1.0. The default value is 0.01, which is very small.

zoomWidthTo

property 
public var zoomWidthTo:Number

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Number that represents the scale at which to complete the width zoom, as a percent between 0.01 and 1.0. The default value is 1.0, which is the object's normal size.

Constructor Detail

Zoom

()Constructor
public function Zoom(target:Object = null)

Language Version: ActionScript 3.0
Product Version: Flex 3
Runtime Versions: Flash Player 9, AIR 1.1

Constructor.

Parameters
target:Object (default = null) — The Object to animate with this effect.
ZoomEffectExample.mxml
<?xml version="1.0" encoding="utf-8"?>
<!-- Simple example to demonstrate the Zoom effect. -->
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
        xmlns:s="library://ns.adobe.com/flex/spark"
        xmlns:mx="library://ns.adobe.com/flex/mx">

    <fx:Script>
        <![CDATA[
            import flash.events.MouseEvent;

            public function doZoom(event:MouseEvent):void {
                if (zoomAll.isPlaying) {
                    zoomAll.reverse();
                }
                else {
                    // If this is a ROLL_OUT event, play the effect backwards.
                    // If this is a ROLL_OVER event, play the effect forwards.
                    zoomAll.play([event.target], event.type == MouseEvent.ROLL_OUT ? true : false);
                }
            }
        ]]>
    </fx:Script>

    <fx:Declarations>
        <mx:Zoom id="zoomAll" zoomWidthTo="1" zoomHeightTo="1" zoomWidthFrom=".5" zoomHeightFrom=".5"  />
    </fx:Declarations>

    <s:Panel title="Zoom Effect Example" width="95%" height="95%" >
        <s:VGroup left="20" right="20" top="20" bottom="20">

            <s:Label width="100%" color="blue"
                text="Move the mouse over the image to enlarge it. Move the mouse off of the image to shrink it."/>

            <mx:Image id="img"
                source="@Embed(source='assets/Nokia_6630.png')"
                scaleX=".5" scaleY=".5"
                rollOver="doZoom(event)"
                rollOut="doZoom(event)"/>
        </s:VGroup>

    </s:Panel>
</s:Application>