ActionScript® 3.0 Reference for the Adobe® Flash® Platform
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mx.effects 

Tween  - AS3 Flex

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adobe.utils
air.desktop
air.net
air.update
air.update.events
coldfusion.air
coldfusion.air.errors
coldfusion.air.events
coldfusion.service
coldfusion.service.events
coldfusion.service.mxml
com.adobe.acm.solutions.authoring.domain.extensions
com.adobe.acm.solutions.ccr.domain.extensions
com.adobe.consulting.pst.vo
com.adobe.dct.component
com.adobe.dct.component.datadictionary
com.adobe.dct.component.datadictionaryElement
com.adobe.dct.component.dataElementsPanel
com.adobe.dct.component.toolbars
com.adobe.dct.event
com.adobe.dct.exp
com.adobe.dct.model
com.adobe.dct.service
com.adobe.dct.service.provider
com.adobe.dct.transfer
com.adobe.dct.util
com.adobe.dct.view
com.adobe.ep.taskmanagement.domain
com.adobe.ep.taskmanagement.event
com.adobe.ep.taskmanagement.filter
com.adobe.ep.taskmanagement.services
com.adobe.ep.taskmanagement.util
com.adobe.ep.ux.attachmentlist.component
com.adobe.ep.ux.attachmentlist.domain
com.adobe.ep.ux.attachmentlist.domain.events
com.adobe.ep.ux.attachmentlist.domain.renderers
com.adobe.ep.ux.attachmentlist.skin
com.adobe.ep.ux.attachmentlist.skin.renderers
com.adobe.ep.ux.content.event
com.adobe.ep.ux.content.factory
com.adobe.ep.ux.content.handlers
com.adobe.ep.ux.content.managers
com.adobe.ep.ux.content.model.asset
com.adobe.ep.ux.content.model.preview
com.adobe.ep.ux.content.model.relation
com.adobe.ep.ux.content.model.search
com.adobe.ep.ux.content.model.toolbar
com.adobe.ep.ux.content.search
com.adobe.ep.ux.content.services
com.adobe.ep.ux.content.services.load
com.adobe.ep.ux.content.services.permissions
com.adobe.ep.ux.content.services.preview
com.adobe.ep.ux.content.services.providers
com.adobe.ep.ux.content.services.query
com.adobe.ep.ux.content.services.relationships
com.adobe.ep.ux.content.services.search.lccontent
com.adobe.ep.ux.content.services.version
com.adobe.ep.ux.content.view
com.adobe.ep.ux.content.view.components.activate
com.adobe.ep.ux.content.view.components.grid
com.adobe.ep.ux.content.view.components.grid.hover
com.adobe.ep.ux.content.view.components.grid.hover.component
com.adobe.ep.ux.content.view.components.grid.renderers
com.adobe.ep.ux.content.view.components.relationships
com.adobe.ep.ux.content.view.components.review
com.adobe.ep.ux.content.view.components.search.renderers
com.adobe.ep.ux.content.view.components.searchpod
com.adobe.ep.ux.content.view.components.toolbar
com.adobe.ep.ux.content.view.components.toolbar.controlRenderers
com.adobe.ep.ux.content.view.components.version
com.adobe.ep.ux.documentsubmit.component
com.adobe.ep.ux.documentsubmit.domain
com.adobe.ep.ux.documentsubmit.skin
com.adobe.ep.ux.taskaction.component
com.adobe.ep.ux.taskaction.domain
com.adobe.ep.ux.taskaction.domain.events
com.adobe.ep.ux.taskaction.skin
com.adobe.ep.ux.taskdetails.component
com.adobe.ep.ux.taskdetails.domain
com.adobe.ep.ux.taskdetails.skin
com.adobe.ep.ux.tasklist.component
com.adobe.ep.ux.tasklist.domain
com.adobe.ep.ux.tasklist.skin
com.adobe.ep.ux.webdocumentviewer.domain
com.adobe.exm.expression
com.adobe.exm.expression.error
com.adobe.exm.expression.event
com.adobe.exm.expression.impl
com.adobe.fiber.runtime.lib
com.adobe.fiber.services
com.adobe.fiber.services.wrapper
com.adobe.fiber.styles
com.adobe.fiber.util
com.adobe.fiber.valueobjects
com.adobe.gravity.binding
com.adobe.gravity.context
com.adobe.gravity.flex.bundleloader
com.adobe.gravity.flex.progress
com.adobe.gravity.flex.serviceloader
com.adobe.gravity.framework
com.adobe.gravity.init
com.adobe.gravity.service.bundleloader
com.adobe.gravity.service.logging
com.adobe.gravity.service.manifest
com.adobe.gravity.service.progress
com.adobe.gravity.tracker
com.adobe.gravity.ui
com.adobe.gravity.utility
com.adobe.gravity.utility.async
com.adobe.gravity.utility.error
com.adobe.gravity.utility.events
com.adobe.gravity.utility.factory
com.adobe.gravity.utility.flex.async
com.adobe.gravity.utility.logging
com.adobe.gravity.utility.message
com.adobe.gravity.utility.sequence
com.adobe.gravity.utility.url
com.adobe.guides.control
com.adobe.guides.domain
com.adobe.guides.i18n
com.adobe.guides.spark.components.skins
com.adobe.guides.spark.components.skins.mx
com.adobe.guides.spark.headers.components
com.adobe.guides.spark.headers.skins
com.adobe.guides.spark.layouts.components
com.adobe.guides.spark.layouts.skins
com.adobe.guides.spark.navigators.components
com.adobe.guides.spark.navigators.renderers
com.adobe.guides.spark.navigators.skins
com.adobe.guides.spark.util
com.adobe.guides.spark.wrappers.components
com.adobe.guides.spark.wrappers.skins
com.adobe.guides.submit
com.adobe.icc.dc.domain
com.adobe.icc.dc.domain.factory
com.adobe.icc.editors.events
com.adobe.icc.editors.handlers
com.adobe.icc.editors.managers
com.adobe.icc.editors.model
com.adobe.icc.editors.model.config
com.adobe.icc.editors.model.el
com.adobe.icc.editors.model.el.operands
com.adobe.icc.editors.model.el.operators
com.adobe.icc.enum
com.adobe.icc.external.dc
com.adobe.icc.obj
com.adobe.icc.services
com.adobe.icc.services.category
com.adobe.icc.services.config
com.adobe.icc.services.download
com.adobe.icc.services.export
com.adobe.icc.services.external
com.adobe.icc.services.formbridge
com.adobe.icc.services.fragmentlayout
com.adobe.icc.services.layout
com.adobe.icc.services.letter
com.adobe.icc.services.locator
com.adobe.icc.services.module
com.adobe.icc.services.render
com.adobe.icc.services.submit
com.adobe.icc.services.user
com.adobe.icc.token
com.adobe.icc.vo
com.adobe.icc.vo.render
com.adobe.icomm.assetplacement.controller
com.adobe.icomm.assetplacement.controller.utils
com.adobe.icomm.assetplacement.data
com.adobe.icomm.assetplacement.model
com.adobe.livecycle.assetmanager.client
com.adobe.livecycle.assetmanager.client.event
com.adobe.livecycle.assetmanager.client.handler
com.adobe.livecycle.assetmanager.client.managers
com.adobe.livecycle.assetmanager.client.model
com.adobe.livecycle.assetmanager.client.model.cms
com.adobe.livecycle.assetmanager.client.service
com.adobe.livecycle.assetmanager.client.service.search
com.adobe.livecycle.assetmanager.client.service.search.cms
com.adobe.livecycle.assetmanager.client.utils
com.adobe.livecycle.content
com.adobe.livecycle.rca.model
com.adobe.livecycle.rca.model.constant
com.adobe.livecycle.rca.model.document
com.adobe.livecycle.rca.model.participant
com.adobe.livecycle.rca.model.reminder
com.adobe.livecycle.rca.model.stage
com.adobe.livecycle.rca.service
com.adobe.livecycle.rca.service.core
com.adobe.livecycle.rca.service.core.delegate
com.adobe.livecycle.rca.service.process
com.adobe.livecycle.rca.service.process.delegate
com.adobe.livecycle.rca.token
com.adobe.livecycle.ria.security.api
com.adobe.livecycle.ria.security.service
com.adobe.mosaic.layouts
com.adobe.mosaic.layouts.dragAndDrop
com.adobe.mosaic.layouts.interfaces
com.adobe.mosaic.mxml
com.adobe.mosaic.om.constants
com.adobe.mosaic.om.events
com.adobe.mosaic.om.impl
com.adobe.mosaic.om.interfaces
com.adobe.mosaic.skinning
com.adobe.mosaic.sparklib.editors
com.adobe.mosaic.sparklib.optionMenu
com.adobe.mosaic.sparklib.scrollableMenu
com.adobe.mosaic.sparklib.scrollableMenu.skins
com.adobe.mosaic.sparklib.tabLayout
com.adobe.mosaic.sparklib.tabLayout.events
com.adobe.mosaic.sparklib.tabLayout.layouts
com.adobe.mosaic.sparklib.tabLayout.skins
com.adobe.mosaic.sparklib.text
com.adobe.mosaic.sparklib.util
com.adobe.solutions.acm.authoring.presentation
com.adobe.solutions.acm.authoring.presentation.actionbar
com.adobe.solutions.acm.authoring.presentation.common
com.adobe.solutions.acm.authoring.presentation.events
com.adobe.solutions.acm.authoring.presentation.fragment
com.adobe.solutions.acm.authoring.presentation.letter
com.adobe.solutions.acm.authoring.presentation.letter.data
com.adobe.solutions.acm.authoring.presentation.preview
com.adobe.solutions.acm.authoring.presentation.rte
com.adobe.solutions.acm.ccr.presentation
com.adobe.solutions.acm.ccr.presentation.contentcapture
com.adobe.solutions.acm.ccr.presentation.contentcapture.events
com.adobe.solutions.acm.ccr.presentation.contentcapture.preview
com.adobe.solutions.acm.ccr.presentation.datacapture
com.adobe.solutions.acm.ccr.presentation.datacapture.renderers
com.adobe.solutions.acm.ccr.presentation.pdf
com.adobe.solutions.exm
com.adobe.solutions.exm.authoring
com.adobe.solutions.exm.authoring.components.controls
com.adobe.solutions.exm.authoring.components.toolbars
com.adobe.solutions.exm.authoring.domain
com.adobe.solutions.exm.authoring.domain.expression
com.adobe.solutions.exm.authoring.domain.impl
com.adobe.solutions.exm.authoring.domain.method
com.adobe.solutions.exm.authoring.domain.variable
com.adobe.solutions.exm.authoring.enum
com.adobe.solutions.exm.authoring.events
com.adobe.solutions.exm.authoring.model
com.adobe.solutions.exm.authoring.renderer
com.adobe.solutions.exm.authoring.view
com.adobe.solutions.exm.expression
com.adobe.solutions.exm.impl
com.adobe.solutions.exm.impl.method
com.adobe.solutions.exm.method
com.adobe.solutions.exm.mock
com.adobe.solutions.exm.mock.method
com.adobe.solutions.exm.runtime
com.adobe.solutions.exm.runtime.impl
com.adobe.solutions.exm.variable
com.adobe.solutions.prm.constant
com.adobe.solutions.prm.domain
com.adobe.solutions.prm.domain.factory
com.adobe.solutions.prm.domain.impl
com.adobe.solutions.prm.domain.manager
com.adobe.solutions.prm.presentation.asset
com.adobe.solutions.prm.presentation.constant
com.adobe.solutions.prm.presentation.document
com.adobe.solutions.prm.presentation.event
com.adobe.solutions.prm.presentation.file
com.adobe.solutions.prm.presentation.project
com.adobe.solutions.prm.presentation.team
com.adobe.solutions.prm.presentation.util
com.adobe.solutions.prm.service
com.adobe.solutions.prm.services.impl
com.adobe.solutions.prm.vo
com.adobe.solutions.rca.constant
com.adobe.solutions.rca.domain
com.adobe.solutions.rca.domain.common
com.adobe.solutions.rca.domain.factory
com.adobe.solutions.rca.domain.impl
com.adobe.solutions.rca.domain.impl.manager
com.adobe.solutions.rca.domain.manager
com.adobe.solutions.rca.presentation
com.adobe.solutions.rca.presentation.comment
com.adobe.solutions.rca.presentation.constant
com.adobe.solutions.rca.presentation.event
com.adobe.solutions.rca.presentation.gantt
com.adobe.solutions.rca.presentation.gantt.ruler
com.adobe.solutions.rca.presentation.template
com.adobe.solutions.rca.presentation.template.audit
com.adobe.solutions.rca.presentation.template.definition
com.adobe.solutions.rca.presentation.template.documents
com.adobe.solutions.rca.presentation.template.stages
com.adobe.solutions.rca.presentation.util
com.adobe.solutions.rca.service
com.adobe.solutions.rca.services.impl
com.adobe.solutions.rca.vo
com.adobe.solutions.rca.vo.um
com.adobe.viewsource
fl.accessibility
fl.containers
fl.controls
fl.controls.dataGridClasses
fl.controls.listClasses
fl.controls.progressBarClasses
fl.core
fl.data
fl.display
fl.events
fl.ik
fl.lang
fl.livepreview
fl.managers
fl.motion
fl.motion.easing
fl.rsl
fl.text
fl.transitions
fl.transitions.easing
fl.video
flash.accessibility
flash.concurrent
flash.crypto
flash.data
flash.desktop
flash.display
flash.display3D
flash.display3D.textures
flash.errors
flash.events
flash.external
flash.filesystem
flash.filters
flash.geom
flash.globalization
flash.html
flash.media
flash.net
flash.net.dns
flash.net.drm
flash.notifications
flash.permissions
flash.printing
flash.profiler
flash.sampler
flash.security
flash.sensors
flash.system
flash.text
flash.text.engine
flash.text.ime
flash.ui
flash.utils
flash.xml
flashx.textLayout
flashx.textLayout.compose
flashx.textLayout.container
flashx.textLayout.conversion
flashx.textLayout.edit
flashx.textLayout.elements
flashx.textLayout.events
flashx.textLayout.factory
flashx.textLayout.formats
flashx.textLayout.operations
flashx.textLayout.utils
flashx.undo
ga.controls
ga.layouts
ga.model
ga.uiComponents
ga.util
ga.views
ga.wrappers
lc.foundation
lc.foundation.domain
lc.foundation.events
lc.foundation.ui
lc.foundation.util
lc.preloader
lc.procmgmt
lc.procmgmt.commands
lc.procmgmt.domain
lc.procmgmt.events
lc.procmgmt.formbridge
lc.procmgmt.impl
lc.procmgmt.ui.attachments
lc.procmgmt.ui.controls
lc.procmgmt.ui.controls.card
lc.procmgmt.ui.controls.renderer
lc.procmgmt.ui.help
lc.procmgmt.ui.layout
lc.procmgmt.ui.presentationmodel
lc.procmgmt.ui.process
lc.procmgmt.ui.search
lc.procmgmt.ui.startpoint
lc.procmgmt.ui.task
lc.procmgmt.ui.task.form
lc.procmgmt.ui.task.form.commands
lc.procmgmt.ui.tracking
mx.accessibility
mx.automation
mx.automation.air
mx.automation.delegates
mx.automation.delegates.advancedDataGrid
mx.automation.delegates.charts
mx.automation.delegates.containers
mx.automation.delegates.controls
mx.automation.delegates.controls.dataGridClasses
mx.automation.delegates.controls.fileSystemClasses
mx.automation.delegates.core
mx.automation.delegates.flashflexkit
mx.automation.events
mx.binding
mx.binding.utils
mx.charts
mx.charts.chartClasses
mx.charts.effects
mx.charts.effects.effectClasses
mx.charts.events
mx.charts.renderers
mx.charts.series
mx.charts.series.items
mx.charts.series.renderData
mx.charts.styles
mx.collections
mx.collections.errors
mx.containers
mx.containers.accordionClasses
mx.containers.dividedBoxClasses
mx.containers.errors
mx.containers.utilityClasses
mx.controls
mx.controls.advancedDataGridClasses
mx.controls.dataGridClasses
mx.controls.listClasses
mx.controls.menuClasses
mx.controls.olapDataGridClasses
mx.controls.scrollClasses
mx.controls.sliderClasses
mx.controls.textClasses
mx.controls.treeClasses
mx.controls.videoClasses
mx.core
mx.core.windowClasses
mx.data
mx.data.crypto
mx.data.errors
mx.data.events
mx.data.messages
mx.data.mxml
mx.data.offline.errors
mx.data.utils
mx.effects
mx.effects.easing
mx.effects.effectClasses
mx.events
mx.filters
mx.flash
mx.formatters
mx.geom
mx.graphics
mx.graphics.codec
mx.graphics.shaderClasses
mx.logging
mx.logging.errors
mx.logging.targets
mx.managers
mx.messaging
mx.messaging.channels
mx.messaging.config
mx.messaging.errors
mx.messaging.events
mx.messaging.management
mx.messaging.messages
mx.modules
mx.netmon
mx.olap
mx.olap.aggregators
mx.preloaders
mx.printing
mx.resources
mx.rpc
mx.rpc.events
mx.rpc.http
mx.rpc.http.mxml
mx.rpc.livecycle
mx.rpc.mxml
mx.rpc.remoting
mx.rpc.remoting.mxml
mx.rpc.soap
mx.rpc.soap.mxml
mx.rpc.wsdl
mx.rpc.xml
mx.skins
mx.skins.halo
mx.skins.spark
mx.skins.wireframe
mx.skins.wireframe.windowChrome
mx.states
mx.styles
mx.utils
mx.validators
org.osmf.containers
org.osmf.display
org.osmf.elements
org.osmf.events
org.osmf.layout
org.osmf.logging
org.osmf.media
org.osmf.metadata
org.osmf.net
org.osmf.net.dvr
org.osmf.net.httpstreaming
org.osmf.net.metrics
org.osmf.net.qos
org.osmf.net.rtmpstreaming
org.osmf.net.rules
org.osmf.traits
org.osmf.utils
spark.accessibility
spark.automation.delegates
spark.automation.delegates.components
spark.automation.delegates.components.gridClasses
spark.automation.delegates.components.mediaClasses
spark.automation.delegates.components.supportClasses
spark.automation.delegates.skins.spark
spark.automation.events
spark.collections
spark.components
spark.components.calendarClasses
spark.components.gridClasses
spark.components.mediaClasses
spark.components.supportClasses
spark.components.windowClasses
spark.core
spark.effects
spark.effects.animation
spark.effects.easing
spark.effects.interpolation
spark.effects.supportClasses
spark.events
spark.filters
spark.formatters
spark.formatters.supportClasses
spark.globalization
spark.globalization.supportClasses
spark.layouts
spark.layouts.supportClasses
spark.managers
spark.modules
spark.preloaders
spark.primitives
spark.primitives.supportClasses
spark.skins
spark.skins.mobile
spark.skins.mobile.supportClasses
spark.skins.spark
spark.skins.spark.mediaClasses.fullScreen
spark.skins.spark.mediaClasses.normal
spark.skins.spark.windowChrome
spark.skins.wireframe
spark.skins.wireframe.mediaClasses
spark.skins.wireframe.mediaClasses.fullScreen
spark.transitions
spark.utils
spark.validators
spark.validators.supportClasses
xd.core.axm.enterprise.view.components
xd.core.axm.enterprise.view.skins
xd.core.axm.view.components
xd.core.axm.view.components.support

Language Elements

Global Constants
Global Functions
Operators
Statements, Keywords & Directives
Special Types

Appendixes

What's New
Compiler Errors
Compiler Warnings
Run-Time Errors
Migrating to ActionScript 3
Supported Character Sets
MXML Only Tags
Motion XML Elements
Timed Text Tags
List of deprecated elements
Accessibility Implementation Constants
How to Use ActionScript Examples
Legal notices
Packagemx.effects
Classpublic class Tween
InheritanceTween 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.animation.Animation class as an alternative to this class.

Tween is the underlying animation class for the effects in Flex 3. As of Flex 4, the Spark effects use the spark.effects.animation.Animation class to provide similar functionality.


The Tween class defines a tween, a property animation performed on a target object over a period of time. That animation can be a change in position, such as performed by the Move effect; a change in size, as performed by the Resize or Zoom effects; a change in visibility, as performed by the Fade or Dissolve effects; or other types of animations.

When defining tween effects, you typically create an instance of the Tween class within your override of the EffectInstance.play() method. A Tween instance accepts the startValue, endValue, and duration properties, and an optional easing function to define the animation.

The Tween object invokes the mx.effects.effectClasses.TweenEffectInstance.onTweenUpdate() callback function on a regular interval on the effect instance for the duration of the effect, passing to the onTweenUpdate() method an interpolated value between the startValue and endValue. Typically, the callback function updates some property of the target object, causing that object to animate over the duration of the effect.

When the effect ends, the Tween objects invokes the mx.effects.effectClasses.TweenEffectInstance.onTweenEnd() callback function, if you defined one.

Learn more

Related API Elements



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  duration : Number = 3000
Duration of the animation, in milliseconds.
Tween
  easingFunction : Function
[write-only] Sets the easing function for the animation.
Tween
  listener : Object
Object that is notified at each interval of the animation.
Tween
Public Methods
 MethodDefined By
  
Tween(listener:Object, startValue:Object, endValue:Object, duration:Number = -1, minFps:Number = -1, updateFunction:Function = null, endFunction:Function = null)
Constructor.
Tween
 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
Dispatches an event into the event flow.
EventDispatcher
  
Interrupt the tween, jump immediately to the end of the tween, and invoke the onTweenEnd() callback function.
Tween
 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
  
Pauses the effect until you call the resume() method.
Tween
 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
  
Resumes the effect after it has been paused by a call to the pause() method.
Tween
  
Plays the effect in reverse, starting from the current position of the effect.
Tween
  
seek(playheadTime:Number):void
Advances the tween effect to the specified position.
Tween
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
  
setTweenHandlers(updateFunction:Function, endFunction:Function):void
By default, the Tween class invokes the mx.effects.effectClasses.TweenEffectInstance.onTweenUpdate() callback function on a regular interval on the effect instance for the duration of the effect, and the optional mx.effects.effectClasses.TweenEffectInstance.onTweenEnd() callback function at the end of the effect duration.
Tween
  
Stops the tween, ending it without dispatching an event or calling the Tween's endFunction or onTweenEnd().
Tween
 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
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
Property Detail

duration

property
public var duration:Number = 3000

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

Duration of the animation, in milliseconds.

easingFunction

property 
easingFunction:Function  [write-only]

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

Sets the easing function for the animation. The easing function is used to interpolate between the startValue value and the endValue. A trivial easing function does linear interpolation, but more sophisticated easing functions create the illusion of acceleration and deceleration, which makes the animation seem more natural.

If no easing function is specified, an easing function based on the Math.sin() method is used.

The easing function follows the function signature popularized by Robert Penner. The function accepts four arguments. The first argument is the "current time", where the animation start time is 0. The second argument is a the initial value at the beginning of the animation (a Number). The third argument is the ending value minus the initial value. The fourth argument is the duration of the animation. The return value is the interpolated value for the current time (usually a value between the initial value and the ending value).

Flex includes a set of easing functions in the mx.effects.easing package.



Implementation
    public function set easingFunction(value:Function):void

listener

property 
public var listener:Object

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

Object that is notified at each interval of the animation.

Constructor Detail

Tween

()Constructor
public function Tween(listener:Object, startValue:Object, endValue:Object, duration:Number = -1, minFps:Number = -1, updateFunction:Function = null, endFunction:Function = null)

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

Constructor.

When the constructor is called, the animation automatically starts playing.

Parameters
listener:Object — Object that is notified at each interval of the animation. You typically pass the this keyword as the value. The listener must define the onTweenUpdate() method and optionally the onTweenEnd() method. The former method is invoked for each interval of the animation, and the latter is invoked just after the animation finishes.
 
startValue:Object — Initial value(s) of the animation. Either a number or an array of numbers. If a number is passed, the Tween interpolates between this number and the number passed in the endValue parameter. If an array of numbers is passed, each number in the array is interpolated.
 
endValue:Object — Final value(s) of the animation. The type of this argument must match the startValue parameter.
 
duration:Number (default = -1) — Duration of the animation, expressed in milliseconds.
 
minFps:Number (default = -1) — Minimum number of times that the onTweenUpdate() method should be called every second. The tween code tries to call the onTweenUpdate() method as frequently as possible (up to 100 times per second). However, if the frequency falls below minFps, the duration of the animation automatically increases. As a result, an animation that temporarily freezes (because it is not getting any CPU cycles) begins again where it left off, instead of suddenly jumping ahead.
 
updateFunction:Function (default = null) — Specifies an alternative update callback function to be used instead of listener.OnTweenUpdate()
 
endFunction:Function (default = null) — Specifies an alternative end callback function to be used instead of listener.OnTweenEnd()
Method Detail

endTween

()method
public function endTween():void

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

Interrupt the tween, jump immediately to the end of the tween, and invoke the onTweenEnd() callback function.

pause

()method 
public function pause():void

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

Pauses the effect until you call the resume() method.

resume

()method 
public function resume():void

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

Resumes the effect after it has been paused by a call to the pause() method.

reverse

()method 
public function reverse():void

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

Plays the effect in reverse, starting from the current position of the effect.

seek

()method 
public function seek(playheadTime:Number):void

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

Advances the tween effect to the specified position.

Parameters

playheadTime:Number — The position, in milliseconds, between 0 and the value of the duration property.

setTweenHandlers

()method 
public function setTweenHandlers(updateFunction:Function, endFunction:Function):void

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

By default, the Tween class invokes the mx.effects.effectClasses.TweenEffectInstance.onTweenUpdate() callback function on a regular interval on the effect instance for the duration of the effect, and the optional mx.effects.effectClasses.TweenEffectInstance.onTweenEnd() callback function at the end of the effect duration.

This method lets you specify different methods as the update and the end callback functions.

Parameters

updateFunction:Function — Specifies the update callback function.
 
endFunction:Function — Specifies the end callback function.

stop

()method 
public function stop():void

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

Stops the tween, ending it without dispatching an event or calling the Tween's endFunction or onTweenEnd().