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flashx.textLayout.compose 

IFlowComposer  - AS3

Packageflashx.textLayout.compose
Interfacepublic interface IFlowComposer
Implementors StandardFlowComposer

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

IFlowComposer defines the interface for managing the layout and display of a text flow.

Text flows displayed with a flow composer implementation can be dynamic and interactive. A flow composer manages one or more display controller. Each controller is associated with a display object container (such as a Sprite) through which the lines created for the text flow are ultimately displayed. The following diagram illustrates the relationship between TextFlow, IFlowComposer, ContainerController, and DisplayObjectContainer objects:

IFlowComposer

A flow composer calculates which portion of a text flow fits in each container and adds the appropriate text lines to the container's display object. The IFlowComposer interface defines separate methods for layout calculations and for updating the display. IFlowComposer also defines methods for incrementally composing and updating a text flow. These methods can be used to avoid blocking the user interface when updating long text flows.

In addition to managing text composition and display, a flow composer controls which container has focus, manages the display of the selection highlight (which can cross container boundaries), and provides direct access to all the TextLine objects in the flow.

To use an IFlowComposer implementation, assign an instance of that implementation to the flowComposer property of a TextFlow object. Call the updateAllControllers() method to lay out and display the text in the containers attached to the flow composer.

Note: For simple, static text flows, you can also use the one of the text line factory classes. These factory classes will typically create lines with less overhead than a flow composer, but do not support editing, dynamic changes, or user interaction.

Related API Elements

ContainerController
FlowComposerBase
StandardFlowComposer
TextFlow
StringTextLineFactory
TextFlowTextLineFactory

Public Properties
 PropertyDefined By
  composing : Boolean
[read-only] True, if the flow composer is currently performing a composition operation.
IFlowComposer
  damageAbsoluteStart : int
[read-only] The first invalid position in the root element, as an absolute position from the start of the flow.
IFlowComposer
  numControllers : int
[read-only] The number of containers assigned to this IFlowComposer instance.
IFlowComposer
  numLines : int
[read-only] The total number of lines composed in the flow.
IFlowComposer
  rootElement : ContainerFormattedElement
[read-only] The root element associated with this IFlowComposer instance.
IFlowComposer
  swfContext : ISWFContext
The ISWFContext instance to be used for calls that must be made in a specific SWF context Implementations of IFlowComposer should allow this property to be set so that users of the interface can create lines in a different SWF context than the one containing the implementation.
IFlowComposer
Public Methods
 MethodDefined By
  
addController(controller:ContainerController):void
Adds a controller to this IFlowComposer instance.
IFlowComposer
  
addControllerAt(controller:ContainerController, index:int):void
Adds a controller to this IFlowComposer instance at the specified index.
IFlowComposer
  
compose():Boolean
Calculates how many lines are necessary to display the content in the root element of the flow and the positions of these lines in the flow's display containers.
IFlowComposer
  
composeToController(index:int):Boolean
Composes the content of the root element up to and including the container at the specified index.
IFlowComposer
  
composeToPosition(absolutePosition:int):Boolean
Composes the content of the root element up to the specified position.
IFlowComposer
  
damage(startPosition:int, damageLength:int, damageType:String):void
Mark lines as damaged and needing a recompose.
IFlowComposer
  
findControllerIndexAtPosition(absolutePosition:int, preferPrevious:Boolean = false):int
Returns the index of the controller containing the content at the specified position.
IFlowComposer
  
findLineAtPosition(absolutePosition:int, preferPrevious:Boolean = false):flashx.textLayout.compose:TextFlowLine
Returns the TextFlowLine object containing the content at the specified position.
IFlowComposer
  
findLineIndexAtPosition(absolutePosition:int, preferPrevious:Boolean = false):int
Returns the sequential line number of the TextFlowLine object that contains the content at the specified position.
IFlowComposer
  
getControllerAt(index:int):ContainerController
Returns the ContainerController object at the specified index.
IFlowComposer
  
getControllerIndex(controller:ContainerController):int
Returns the index of the specified ContainerController object.
IFlowComposer
  
getLineAt(index:int):flashx.textLayout.compose:TextFlowLine
Returns the line with the specified line number.
IFlowComposer
  
interactionManagerChanged(newInteractionManager:ISelectionManager):void
Called by the TextFlow when the interaction manager changes.
IFlowComposer
  
isDamaged(absolutePosition:int):Boolean
Indicates whether any TextFlowLine objects between the beginning of the flow and the line containing the content at the specified position are marked as damaged.
IFlowComposer
  
removeAllControllers():void
Removes all controllers from this IFlowComposer instance.
IFlowComposer
  
removeController(controller:ContainerController):void
Removes a controller from this IFlowComposer instance.
IFlowComposer
  
removeControllerAt(index:int):void
Removes the controller at the specified index from this IFlowComposer instance.
IFlowComposer
  
setFocus(absolutePosition:int, preferPrevious:Boolean = false):void
Sets the focus to the container that contains the location specified by the absolutePosition parameter.
IFlowComposer
  
setRootElement(newRootElement:ContainerFormattedElement):void
IFlowComposer
  
updateAllControllers():Boolean
Composes the content of the root element and updates the display.
IFlowComposer
  
updateLengths(startPosition:int, deltaLength:int):void
Update the lengths in the lines to maintain mapping to the TextFlow.
IFlowComposer
  
updateToController(index:int):Boolean
Composes and updates the display up to and including the container at the specified index.
IFlowComposer
Property Detail

composing

property
composing:Boolean  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

True, if the flow composer is currently performing a composition operation.



Implementation
    public function get composing():Boolean

damageAbsoluteStart

property 
damageAbsoluteStart:int  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

The first invalid position in the root element, as an absolute position from the start of the flow.



Implementation
    public function get damageAbsoluteStart():int

numControllers

property 
numControllers:int  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

The number of containers assigned to this IFlowComposer instance.



Implementation
    public function get numControllers():int

numLines

property 
numLines:int  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

The total number of lines composed in the flow. By default TLF does not compose the entire flow and this value may be innacruate. Use composeToPosition to get all lines composed.



Implementation
    public function get numLines():int

rootElement

property 
rootElement:ContainerFormattedElement  [read-only]

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

The root element associated with this IFlowComposer instance.

Only a TextFlow object can be a root element.



Implementation
    public function get rootElement():ContainerFormattedElement

Related API Elements

ContainerFormattedElement

swfContext

property 
swfContext:ISWFContext

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

The ISWFContext instance to be used for calls that must be made in a specific SWF context

Implementations of IFlowComposer should allow this property to be set so that users of the interface can create lines in a different SWF context than the one containing the implementation. A default implementation of ISWFContext should also be supplied.



Implementation
    public function get swfContext():ISWFContext
    public function set swfContext(value:ISWFContext):void

Related API Elements

ISWFContext
Method Detail

addController

()method
public function addController(controller:ContainerController):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Adds a controller to this IFlowComposer instance.

The container is added to the end of the container list.

Parameters

controller:ContainerController — The ContainerController object to add.

addControllerAt

()method 
public function addControllerAt(controller:ContainerController, index:int):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Adds a controller to this IFlowComposer instance at the specified index.

The list of controllers is 0-based (the first controller has an index of 0).

Parameters

controller:ContainerController — The ContainerController object to add.
 
index:int — A numeric index that specifies the position in the controller list at which to insert the ContainerController object.

compose

()method 
public function compose():Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Calculates how many lines are necessary to display the content in the root element of the flow and the positions of these lines in the flow's display containers.

Implementations of this method should not update the display, but should save the results so that subsequent calls to compose() or updateAllControllers() do not perform an additional recomposition if the flow content has not changed.

If the contents of any container have changed, the method must return true.

Returns
Boolean — true if anything changed.

Related API Elements

updateAllControllers()
updateToController()

composeToController

()method 
public function composeToController(index:int):Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Composes the content of the root element up to and including the container at the specified index.

If the contents of any container up to and including the container at the specified index has changed, the method returns true. If index is greater than the number of controllers (or not specified), then all containers are composed.

Parameters

index:int (default = NaN) — compose at least up to this container in the TextFlow. If controllerIndex is greater than the number of controllers, compose to the end of the last container.

Returns
Boolean — true if anything changed.

Related API Elements

updateAllControllers()
updateToController()

composeToPosition

()method 
public function composeToPosition(absolutePosition:int):Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Composes the content of the root element up to the specified position.

If the contents of any container up to and including the container holding the content at the specified position has changed, the method returns true. If absolutePosition is greater than the length of the TextFlow (or not specified), then the entire flow is composed.

Parameters

absolutePosition:int (default = NaN) — compose at least up to this position in the TextFlow. By default or if absolutePosition is past the end of the flow compose to the end of the flow.

Returns
Boolean — true if anything changed.

Related API Elements

updateAllControllers()
updateToController()

damage

()method 
public function damage(startPosition:int, damageLength:int, damageType:String):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Mark lines as damaged and needing a recompose.

Parameters

startPosition:int — beginning of range to damage
 
damageLength:int — number of characters to damage
 
damageType:String — type of damage. One of flashx.textLayout.compose.FlowDamageType

Related API Elements

flashx.textLayout.compose.FlowDamageType

findControllerIndexAtPosition

()method 
public function findControllerIndexAtPosition(absolutePosition:int, preferPrevious:Boolean = false):int

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Returns the index of the controller containing the content at the specified position.

A position can be considered to be the division between two characters or other elements of a text flow. If the value in absolutePosition is a position between the last character of one container and the first character of the next, then the preceding container is returned if the preferPrevious parameter is set to true and the later container is returned if the preferPrevious parameter is set to false.

The method must return -1 if the content at the specified position is not in any container or is outside the range of positions in the text flow.

Parameters

absolutePosition:int — The position of the content for which the container index is sought.
 
preferPrevious:Boolean (default = false) — Specifies which container index to return when the position is between the last element in one container and the first element in the next.

Returns
int — the index of the container controller or -1 if not found.

findLineAtPosition

()method 
public function findLineAtPosition(absolutePosition:int, preferPrevious:Boolean = false):flashx.textLayout.compose:TextFlowLine

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Returns the TextFlowLine object containing the content at the specified position.

A position can be considered to be the division between two characters or other elements of a text flow. If the value in absolutePosition is a position between the last element of one line and the first element of the next, then the preceding line is returned if the preferPrevious parameter is set to true and the later line is returned if the preferPrevious parameter is set to false.

Parameters

absolutePosition:int — The position of the content for which you want the TextFlowLine object.
 
preferPrevious:Boolean (default = false) — Specifies which line to return when the position is between the last element of one line and the first element of the next.

Returns
flashx.textLayout.compose:TextFlowLine — the TextFlowLine containing the content at the specified position, or null if not found.

findLineIndexAtPosition

()method 
public function findLineIndexAtPosition(absolutePosition:int, preferPrevious:Boolean = false):int

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Returns the sequential line number of the TextFlowLine object that contains the content at the specified position.

The number of the first line is 0 and the number of the last line is equal to the number of lines minus one. If the position specified in absolutePosition is past the end of the text flow, this method must return the number that will be assigned to the next new line added to the text flow (which is equal to the number of current lines).

A position can be considered to be the division between two characters or other elements of a text flow. If the value in absolutePosition is a position between the last line of one container and the first line of the next, then the preceding container is returned if the preferPrevious parameter is set to true and the later container is returned if the preferPrevious parameter is set to false.

Parameters

absolutePosition:int — The position of the content for which you want the text line.
 
preferPrevious:Boolean (default = false) — Specifies which container index to return when the position is between the last line in one container and the first line in the next.

Returns
int — the index of the text line at the specified position. If not found, treats as past the end and returns the number of lines.

getControllerAt

()method 
public function getControllerAt(index:int):ContainerController

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Returns the ContainerController object at the specified index.

Parameters

index:int — The index of the ContainerController object to return.

Returns
ContainerController — the ContainerController object at the specified position.

getControllerIndex

()method 
public function getControllerIndex(controller:ContainerController):int

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Returns the index of the specified ContainerController object.

Parameters

controller:ContainerController — A reference to the ContainerController object to find.

Returns
int — the index of the specified ContainerController object or -1 if the controller is not attached to this flow composer.

getLineAt

()method 
public function getLineAt(index:int):flashx.textLayout.compose:TextFlowLine

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Returns the line with the specified line number.

The list of lines is numbered from zero to the number of lines minus one. If the value in index is outside the bounds of the list of lines, then this function returns null.

Parameters

index:int — The line number of the TextFlowLine object to return.

Returns
flashx.textLayout.compose:TextFlowLine — the TextFlowLine with the specified line number, or null, if not found.

interactionManagerChanged

()method 
public function interactionManagerChanged(newInteractionManager:ISelectionManager):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Called by the TextFlow when the interaction manager changes.

Implementations of IFlowComposer should update event listeners and properties that reference the interaction manager.

Parameters

newInteractionManager:ISelectionManager — The new ISelectionManager instance.

isDamaged

()method 
public function isDamaged(absolutePosition:int):Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Indicates whether any TextFlowLine objects between the beginning of the flow and the line containing the content at the specified position are marked as damaged.

Parameters

absolutePosition:int — the last position in the area of interest

Returns
Boolean — true if any of the TextFlowLine objects from the start of the flow up to the line containing the content at absolutePosition are marked as damaged.

removeAllControllers

()method 
public function removeAllControllers():void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Removes all controllers from this IFlowComposer instance.

removeController

()method 
public function removeController(controller:ContainerController):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Removes a controller from this IFlowComposer instance.

Parameters

controller:ContainerController — The ContainerController instance to remove.

removeControllerAt

()method 
public function removeControllerAt(index:int):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Removes the controller at the specified index from this IFlowComposer instance.

Parameters

index:int — The index of the ContainerController object to remove.

setFocus

()method 
public function setFocus(absolutePosition:int, preferPrevious:Boolean = false):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Sets the focus to the container that contains the location specified by the absolutePosition parameter.

It is the responsibility of the implementation to define what setting the focus means. For example, an implementation could use the built-in focus property of the Stage object (as long as the containers were InteractiveObjects) or the implementation could manage the focus some other way.

Parameters

absolutePosition:int — Specifies the position in the text flow of the container to receive focus.
 
preferPrevious:Boolean (default = false) — If true and the position is the before the first character in a container, sets focus to the end of the previous container.

Related API Elements

flash.display.Stage.focus

setRootElement

()method 
public function setRootElement(newRootElement:ContainerFormattedElement):void

Parameters

newRootElement:ContainerFormattedElement

updateAllControllers

()method 
public function updateAllControllers():Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Composes the content of the root element and updates the display.

Text layout is typically conducted in two phases: composition and display. In the composition phase, the flow composer calculates how many lines are necesary to display the content as well as the position of these lines in the flow's display containers. In the display phase, the flow composer updates the display object children of its containers. The updateAllControllers() method is expected to carry out both phases. An efficient implementation will keep track of changes to content so that a full cycle of composition and display is only performed when necessary.

This method updates all the text lines and the display list immediately and synchronously.

If the contents of any container is changed, the method must return true.

Returns
Boolean — true if anything changed.

updateLengths

()method 
public function updateLengths(startPosition:int, deltaLength:int):void

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Update the lengths in the lines to maintain mapping to the TextFlow.

Parameters

startPosition:int — beginning of change in length
 
deltaLength:int — change in number of characters.

updateToController

()method 
public function updateToController(index:int):Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 10, AIR 1.5

Composes and updates the display up to and including the container at the specified index.

The updateToController() method is expected to both compose the content and update the display so that all containers up to and including the container at the specified index are current. For example, if you have a chain of twenty containers and specify an index of 10, updateToController() must ensures that the first through the tenth (indexes 0-9) containers are composed and displayed. Composition can stop at that point. If controllerIndex is -1 (or not specified), then all containers should be updated.

This method updates all the text lines and the display list immediately and synchronously.

If the contents of any container is changed, the method must return true.

Parameters

index:int (default = NaN) — index of the last container to update, by default will update all containers

Returns
Boolean — true if anything changed.



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Thu Dec 4 2014, 05:50 PM -08:00
 

 

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