| Package | mx.core |
| Class | public class BitmapAsset |
| Inheritance | BitmapAsset  FlexBitmap Bitmap DisplayObject EventDispatcher Object |
| Implements | IFlexAsset, IFlexDisplayObject, ILayoutDirectionElement |
| Language Version: | ActionScript 3.0 |
| Product Version: | Flex 3 |
| Runtime Versions: | Flash Player 9, AIR 1.1 |
The bitmap image that you're embedding can be in a JPEG, GIF, or PNG file. You can also embed a bitmap symbol that is in a SWF file produced by Flash. In each of these cases, the MXML compiler autogenerates a class that extends BitmapAsset to represent the embedded bitmap image.
You don't generally have to use the BitmapAsset class directly when you write a Flex application. For example, you can embed a GIF file and display the image in an Image control by writing the gollowing:
<mx:Image id="logo" source="@Embed(source='Logo.gif')"/>
or use it as the application's background image in CSS syntax by writing
<fx:Style>
@namespace mx "library://ns.adobe.com/flex/mx"
mx|Application {
backgroundImage: Embed(source="Logo.gif")
}
<fx:Style/>
without having to understand that the MXML compiler has created a subclass of BitmapAsset for you.
However, it may be useful to understand what is happening
at the ActionScript level.
To embed a bitmap image in ActionScript, you declare a variable
of type Class, and put [Embed] metadata on it.
For example, you embed a GIF file like this:
[Bindable] [Embed(source="Logo.gif")] private var logoClass:Class;
The MXML compiler sees the .gif extension, transcodes the GIF data
into the bitmap format that the player uses, autogenerates
a subclass of the BitmapAsset class, and sets your variable
to be a reference to this autogenerated class.
You can then use this class reference to create instances of the
BitmapAsset using the new operator, and you can use
APIs of the BitmapAsset class on them:
var logo:BitmapAsset = BitmapAsset(new logoClass()); logo.bitmapData.noise(4);
However, you rarely need to create BitmapAsset instances yourself
because image-related properties and styles can simply be set to an
image-producing class, and components will create image instances
as necessary.
For example, to display this image in an Image control, you can
set the Image's source property to logoClass.
In MXML you could do this as follows:
<mx:Image id="logo" source="{logoClass}"/>
Hide Inherited Public Properties
Show Inherited Public Properties| Property | Defined By | ||
|---|---|---|---|
 | accessibilityProperties : AccessibilityProperties
The current accessibility options for this display object. | DisplayObject | |
| alpha : Number
Indicates the alpha transparency value of the object specified. | DisplayObject | |
| bitmapData : BitmapData
The BitmapData object being referenced. | Bitmap | |
| blendMode : String
A value from the BlendMode class that specifies which blend mode to use. | DisplayObject | |
| blendShader : Shader [write-only]
Sets a shader that is used for blending the foreground and background. | DisplayObject | |
| cacheAsBitmap : Boolean
If set to true, Flash runtimes cache an internal bitmap representation of the
display object. | DisplayObject | |
| cacheAsBitmapMatrix : Matrix
If non-null, this Matrix object defines how a display object is rendered when
cacheAsBitmap is set to true. | DisplayObject | |
| constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | |
| filters : Array
An indexed array that contains each filter object currently associated with the display object. | DisplayObject | |
| height : Number
Indicates the height of the display object, in pixels. | DisplayObject | |
| layoutDirection : String
Specifies the desired layout direction for an element: one of LayoutDirection.LTR
(left to right), LayoutDirection.RTL (right to left), or null (inherit). | BitmapAsset | ||
| loaderInfo : LoaderInfo [read-only]
Returns a LoaderInfo object containing information about loading the file
to which this display object belongs. | DisplayObject | |
| mask : DisplayObject
The calling display object is masked by the specified mask object. | DisplayObject | |
| measuredHeight : Number [read-only]
The measured height of this object. | BitmapAsset | ||
| measuredWidth : Number [read-only]
The measured width of this object. | BitmapAsset | ||
| mouseX : Number [read-only]
Indicates the x coordinate of the mouse or user input device position, in pixels. | DisplayObject | |
| mouseY : Number [read-only]
Indicates the y coordinate of the mouse or user input device position, in pixels. | DisplayObject | |
| name : String
Indicates the instance name of the DisplayObject. | DisplayObject | |
| opaqueBackground : Object
Specifies whether the display object is opaque with a certain background color. | DisplayObject | |
| parent : DisplayObjectContainer [read-only]
Indicates the DisplayObjectContainer object that contains this display object. | DisplayObject | |
| pixelSnapping : String
Controls whether or not the Bitmap object is snapped to the nearest pixel. | Bitmap | |
| prototype : Object [static]
A reference to the prototype object of a class or function object. | Object | |
| root : DisplayObject [read-only]
For a display object in a loaded SWF file, the root property is the
top-most display object in the portion of the display list's tree structure represented by that SWF file. | DisplayObject | |
| rotation : Number
Indicates the rotation of the DisplayObject instance, in degrees, from its original orientation. | DisplayObject | |
| rotationX : Number
Indicates the x-axis rotation of the DisplayObject instance, in degrees, from its original orientation relative to the 3D parent container. | DisplayObject | |
| rotationY : Number
Indicates the y-axis rotation of the DisplayObject instance, in degrees, from its original orientation relative to the 3D parent container. | DisplayObject | |
| rotationZ : Number
Indicates the z-axis rotation of the DisplayObject instance, in degrees, from its original orientation relative to the 3D parent container. | DisplayObject | |
| scale9Grid : Rectangle
The current scaling grid that is in effect. | DisplayObject | |
| scaleX : Number
Indicates the horizontal scale (percentage) of the object as applied from the registration point. | DisplayObject | |
| scaleY : Number
Indicates the vertical scale (percentage) of an object as applied from the registration point of the object. | DisplayObject | |
| scaleZ : Number
Indicates the depth scale (percentage) of an object as applied from the registration point of the object. | DisplayObject | |
| scrollRect : Rectangle
The scroll rectangle bounds of the display object. | DisplayObject | |
| smoothing : Boolean
Controls whether or not the bitmap is smoothed when scaled. | Bitmap | |
| stage : Stage [read-only]
The Stage of the display object. | DisplayObject | |
| transform : flash.geom:Transform
An object with properties pertaining to a display object's matrix, color transform, and pixel bounds. | DisplayObject | |
| visible : Boolean
Whether or not the display object is visible. | DisplayObject | |
| width : Number
Indicates the width of the display object, in pixels. | DisplayObject | |
| x : Number
Indicates the x coordinate of the DisplayObject instance relative to the local coordinates of
the parent DisplayObjectContainer. | DisplayObject | |
| y : Number
Indicates the y coordinate of the DisplayObject instance relative to the local coordinates of
the parent DisplayObjectContainer. | DisplayObject | |
| z : Number
Indicates the z coordinate position along the z-axis of the DisplayObject
instance relative to the 3D parent container. | DisplayObject | |
| Method | Defined By | ||
|---|---|---|---|
Constructor. | BitmapAsset | ||
| 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 | |
|
Dispatches an event into the event flow. | EventDispatcher | |
|
Returns a rectangle that defines the area of the display object relative to the coordinate system
of the targetCoordinateSpace object. | DisplayObject | |
|
Returns a rectangle that defines the boundary of the display object,
based on the coordinate system defined by the targetCoordinateSpace
parameter, excluding any strokes on shapes. | DisplayObject | |
|
Converts the point object from the Stage (global) coordinates
to the display object's (local) coordinates. | DisplayObject | |
|
Converts a two-dimensional point from the Stage (global) coordinates to a
three-dimensional display object's (local) coordinates. | DisplayObject | |
|
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 | |
|
Evaluates the bounding box of the display object to see if it overlaps or intersects with the
bounding box of the obj display object. | DisplayObject | |
|
Evaluates the display object to see if it overlaps or intersects with the
point specified by the x and y parameters. | DisplayObject | |
An element must call this method when its layoutDirection changes or
when its parent's layoutDirection changes. | BitmapAsset | ||
|
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | |
|
Converts a three-dimensional point of the three-dimensional display
object's (local) coordinates to a two-dimensional point in the Stage (global) coordinates. | DisplayObject | |
|
Converts the point object from the display object's (local) coordinates to the
Stage (global) coordinates. | DisplayObject | |
Moves this object to the specified x and y coordinates. | BitmapAsset | ||
|
Indicates whether the specified property exists and is enumerable. | Object | |
|
Removes a listener from the EventDispatcher object. | EventDispatcher | |
Sets the actual size of this object. | BitmapAsset | ||
|
Sets the availability of a dynamic property for loop operations. | Object | |
|
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | |
| [override]
Returns a string indicating the location of this object
within the hierarchy of DisplayObjects in the Application. | FlexBitmap | |
|
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 | |
layoutDirection | property |
layoutDirection:String| Language Version: | ActionScript 3.0 |
| Product Version: | Flex 4.1 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
Specifies the desired layout direction for an element: one of LayoutDirection.LTR (left to right), LayoutDirection.RTL (right to left), or null (inherit). This property is typically backed by an inheriting style. If null, the layoutDirection style will be set to undefined. Classes like GraphicElement, which implement ILayoutDirectionElement but do not support styles, must additionally support a null value for this property which means the layoutDirection must be inherited from its parent.
Implementation
public function get layoutDirection():String public function set layoutDirection(value:String):voidmeasuredHeight | property |
measuredHeight:Number [read-only] | Language Version: | ActionScript 3.0 |
| Product Version: | Flex 3 |
| Runtime Versions: | Flash Player 9, AIR 1.1 |
The measured height of this object.
This is typically hard-coded for graphical skins
because this number is simply the number of pixels in the graphic.
For code skins, it can also be hard-coded
if you expect to be drawn at a certain size.
If your size can change based on properties, you may want
to also be an ILayoutManagerClient so a measure()
method will be called at an appropriate time,
giving you an opportunity to compute a measuredHeight.
Implementation
public function get measuredHeight():NumbermeasuredWidth | property |
measuredWidth:Number [read-only] | Language Version: | ActionScript 3.0 |
| Product Version: | Flex 3 |
| Runtime Versions: | Flash Player 9, AIR 1.1 |
The measured width of this object.
This is typically hard-coded for graphical skins
because this number is simply the number of pixels in the graphic.
For code skins, it can also be hard-coded
if you expect to be drawn at a certain size.
If your size can change based on properties, you may want
to also be an ILayoutManagerClient so a measure()
method will be called at an appropriate time,
giving you an opportunity to compute a measuredHeight.
Implementation
public function get measuredWidth():NumberBitmapAsset | () | Constructor |
public function BitmapAsset(bitmapData:BitmapData = null, pixelSnapping:String = "auto", smoothing:Boolean = false)| Language Version: | ActionScript 3.0 |
| Product Version: | Flex 3 |
| Runtime Versions: | Flash Player 9, AIR 1.1 |
Constructor.
ParametersbitmapData:BitmapData (default = null) | |
pixelSnapping:String (default = "auto") | |
smoothing:Boolean (default = false) |
invalidateLayoutDirection | () | method |
public function invalidateLayoutDirection():void| Language Version: | ActionScript 3.0 |
| Product Version: | Flex 4.1 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
An element must call this method when its layoutDirection changes or when its parent's layoutDirection changes. If they differ, this method is responsible for mirroring the element’s contents and for updating the element’s post-layout transform so that descendants inherit a mirrored coordinate system. IVisualElements typically implement mirroring by using postLayoutTransformOffsets to scale the X axis by -1 and to translate the x coordinate of the origin by the element's width. The net effect of this "mirror" transform is to reverse the direction in which the X axis increases without changing the element's location relative to its parent's origin.
move | () | method |
public function move(x:Number, y:Number):void| Language Version: | ActionScript 3.0 |
| Product Version: | Flex 3 |
| Runtime Versions: | Flash Player 9, AIR 1.1 |
Moves this object to the specified x and y coordinates.
Parameters
x:Number — The new x-position for this object.
| |
y:Number — The new y-position for this object.
|
setActualSize | () | method |
public function setActualSize(newWidth:Number, newHeight:Number):void| Language Version: | ActionScript 3.0 |
| Product Version: | Flex 3 |
| Runtime Versions: | Flash Player 9, AIR 1.1 |
Sets the actual size of this object.
This method is mainly for use in implementing the
updateDisplayList() method, which is where
you compute this object's actual size based on
its explicit size, parent-relative (percent) size,
and measured size.
You then apply this actual size to the object
by calling setActualSize().
In other situations, you should be setting properties
such as width, height,
percentWidth, or percentHeight
rather than calling this method.
Parameters
newWidth:Number — The new width for this object.
| |
newHeight:Number — The new height for this object.
|
Mon Nov 28 2011, 06:48 AM -08:00