The SparkDownloadProgressBar class displays download progress.
It is used by the Preloader control to provide user feedback
while the application is downloading and loading.
The download progress bar displays information about
two different phases of the application:
the download phase and the initialization phase.
In the Application container, use the
the preloader property to specify the name of your subclass.
You can implement a custom download progress bar component
by creating a subclass of the SparkDownloadProgressBar class.
Do not implement a download progress bar as an MXML component
because it loads too slowly.
Defines the algorithm for determining whether to show the download progress bar
while in the initialization phase, assuming that the display
is not currently visible.
SparkDownloadProgressBar
Property Detail
backgroundAlpha
property
backgroundAlpha:Number
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Alpha level of the SWF file or image defined by
the backgroundImage property, or the color defined by
the backgroundColor property.
Valid values range from 0 to 1.0.
Override this property to set your own value in a custom class.
You can specify either a backgroundColor
or a backgroundImage, but not both.
The default value is 1.0.
Implementation public function get backgroundAlpha():Number public function set backgroundAlpha(value:Number):void
backgroundColor
property
backgroundColor:uint
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Background color of a download progress bar.
Override this property to set your own value in a custom class.
You can specify either a backgroundColor
or a backgroundImage, but not both.
Implementation public function get backgroundColor():uint public function set backgroundColor(value:uint):void
backgroundImage
property
backgroundImage:Object
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
The background image of the application,
which is passed in by the preloader.
Override this property to set your own value in a custom class.
You can specify either a backgroundColor
or a backgroundImage, but not both.
A value of null means "not set".
If this style and the backgroundColor style are undefined,
the component has a transparent background.
The preloader does not display embedded images.
You can only use images loaded at runtime.
The default value is null.
Implementation public function get backgroundImage():Object public function set backgroundImage(value:Object):void
backgroundSize
property
backgroundSize:String
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Scales the image specified by backgroundImage
to different percentage sizes.
A value of "100%" stretches the image
to fit the entire component.
To specify a percentage value, you must include the percent sign (%).
A value of "auto", maintains
the original size of the image.
The default value is "auto".
Implementation public function get backgroundSize():String public function set backgroundSize(value:String):void
initProgressTotal
property
protected var initProgressTotal:uint = 6
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
The total number of validation events you expect to get
in the initializing phase. This should be an integer
greater or equal to 4 (and note that if it is greater than 4
you might have an inefficiency in your initialization code)
The default value is 6.
preloader
property
preloader:Sprite [write-only]
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
The Preloader class passes in a reference to itself to the display class
so that it can listen for events from the preloader.
Implementation public function set preloader(value:Sprite):void
stageHeight
property
stageHeight:Number
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
The height of the stage,
which is passed in by the Preloader class.
Implementation public function get stageHeight():Number public function set stageHeight(value:Number):void
stageWidth
property
stageWidth:Number
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
The width of the stage,
which is passed in by the Preloader class.
Implementation public function get stageWidth():Number public function set stageWidth(value:Number):void
visible
property
visible:Boolean[override]
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Specifies whether the download progress bar is visible.
When the Preloader control determines that the progress bar should be displayed,
it sets this value to true. When the Preloader control determines that
the progress bar should be hidden, it sets the value to false.
A subclass of the SparkDownloadProgressBar class should never modify this property.
Instead, you can override the setter method to recognize when
the Preloader control modifies it, and perform any necessary actions.
The default value is false.
Implementation public function get visible():Boolean public function set visible(value:Boolean):void
Constructor Detail
SparkDownloadProgressBar
()
Constructor
public function SparkDownloadProgressBar()
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Constructor.
Method Detail
completeHandler
()
method
protected function completeHandler(event:Event):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Event listener for the Event.COMPLETE event.
The default implementation does nothing.
Parameters
event:Event — The event object.
createChildren
()
method
protected function createChildren():void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Creates the subcomponents of the display.
initCompleteHandler
()
method
protected function initCompleteHandler(event:Event):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Event listener for the FlexEvent.INIT_COMPLETE event.
This implementation dispatches a Event.COMPLETE event.
Parameters
event:Event — The event object
initialize
()
method
public function initialize():void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Called by the Preloader after the download progress bar
has been added as a child of the Preloader.
This should be the starting point for configuring your download progress bar.
initProgressHandler
()
method
protected function initProgressHandler(event:Event):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Event listener for the FlexEvent.INIT_PROGRESS event.
This implementation updates the progress bar
each time the event is dispatched.
Parameters
event:Event — The event object.
progressHandler
()
method
protected function progressHandler(event:ProgressEvent):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Event listener for the ProgressEvent.PROGRESS event.
This implementation updates the progress bar
with the percentage of bytes downloaded.
Parameters
event:ProgressEvent — The event object.
rslCompleteHandler
()
method
protected function rslCompleteHandler(event:RSLEvent):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Event listener for the RSLEvent.RSL_COMPLETE event.
protected function setDownloadProgress(completed:Number, total:Number):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Updates the outer portion of the download progress bar to
indicate download progress.
Parameters
completed:Number — Number of bytes of the application SWF file
that have been downloaded.
total:Number — Size of the application SWF file in bytes.
setInitProgress
()
method
protected function setInitProgress(completed:Number, total:Number):void
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Updates the inner portion of the download progress bar to
indicate initialization progress.
Parameters
completed:Number — Number of initialization steps that
have been completed
total:Number — Total number of initialization steps
showDisplayForDownloading
()
method
protected function showDisplayForDownloading(elapsedTime:int, event:ProgressEvent):Boolean
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Defines the algorithm for determining whether to show
the download progress bar while in the download phase.
Parameters
elapsedTime:int — Number of milliseconds that have elapsed
since the start of the download phase.
event:ProgressEvent — The ProgressEvent object that contains
the bytesLoaded and bytesTotal properties.
Returns
Boolean — If the return value is true, then show the
download progress bar.
The default behavior is to show the download progress bar
if more than 700 milliseconds have elapsed
and if Flex has downloaded less than half of the bytes of the SWF file.
showDisplayForInit
()
method
protected function showDisplayForInit(elapsedTime:int, count:int):Boolean
Language Version :
ActionScript 3.0
Product Version :
Flex 4
Runtime Versions :
Flash Player 10, AIR 1.5
Defines the algorithm for determining whether to show the download progress bar
while in the initialization phase, assuming that the display
is not currently visible.
Parameters
elapsedTime:int — Number of milliseconds that have elapsed
since the start of the download phase.
count:int — number of times that the initProgress event
has been received from the application.
Returns
Boolean — If true, then show the download progress bar.