| Package | flashx.textLayout.events |
| Class | public class FlowOperationEvent |
| Inheritance | FlowOperationEvent  Event Object |
| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
Before any operation is carried out, a TextFlow object dispatches a FlowOperationEvent
with its type property set to FlowOperationEvent.FLOW_OPERATION_BEGIN.
You can determine what type of operation is about to commence by checking
the operation property. Events of type FLOW_OPERATION_BEGIN are
cancellable, which means that if you decide that the operation should not proceed,
you can call Event.PreventDefault() to cancel the operation.
If you cancel the operation, the operation is not performed and the
FLOW_OPERATION_END event is not dispatched. You may also choose to call back into the
EditManager to do another operation before the operation that triggered the event is done. If you do
this, the operations you initiate in your event handler will be undone as a single
operation with the operation that triggered the event.
If you allow the operation to proceed, TextFlow will dispatch a FlowOperationEvent
upon completion of the operation with its type property set to
FlowOperationEvent.FLOW_OPERATION_END. This event is dispatched
before Flash Player throws any errors that may have occurred as a result of the
operation. This gives you an opportunity to process the error before Flash Player
throws the error. You can access the error through the event's error
property. If you choose to handle the error in your event handler, you can prevent
Flash Player from throwing the error by cancelling the FLOW_OPERATION_END event
by calling Event.preventDefault(). You may also choose to call back into the
EditManager to do some additional operations. If you do this, the operations that result
will be undone as a unit with the operation that triggered the event.
Related API Elements
Hide Inherited Public Properties
Show Inherited Public Properties| Property | Defined By | ||
|---|---|---|---|
 | bubbles : Boolean [read-only]
Indicates whether an event is a bubbling event. | Event | |
| cancelable : Boolean [read-only]
Indicates whether the behavior associated with the event can be prevented. | Event | |
| constructor : Object
A reference to the class object or constructor function for a given object instance. | Object | |
| currentTarget : Object [read-only]
The object that is actively processing the Event object with an event listener. | Event | |
| error : Error
The error thrown, if any, during an operation. | FlowOperationEvent | ||
| eventPhase : uint [read-only]
The current phase in the event flow. | Event | |
| level : int
Operations may be merged into composite operations through nesting. | FlowOperationEvent | ||
| operation : FlowOperation
The operation that is about to begin or has just ended. | FlowOperationEvent | ||
| target : Object [read-only]
The event target. | Event | |
| type : String [read-only]
The type of event. | Event | |
| Method | Defined By | ||
|---|---|---|---|
FlowOperationEvent(type:String, bubbles:Boolean = false, cancelable:Boolean = false, operation:FlowOperation = null, level:int = 0, error:Error = null) Creates an event object that contains information about a flow operation. | FlowOperationEvent | ||
|
Duplicates an instance of an Event subclass. | Event | |
|
A utility function for implementing the toString() method in custom
ActionScript 3.0 Event classes. | Event | |
|
Indicates whether an object has a specified property defined. | Object | |
|
Checks whether the preventDefault() method has been called on the event. | Event | |
|
Indicates whether an instance of the Object class is in the prototype chain of the object specified
as the parameter. | Object | |
|
Cancels an event's default behavior if that behavior can be canceled. | Event | |
|
Indicates whether the specified property exists and is enumerable. | Object | |
|
Sets the availability of a dynamic property for loop operations. | Object | |
|
Prevents processing of any event listeners in the current node and any subsequent nodes in
the event flow. | Event | |
|
Prevents processing of any event listeners in nodes subsequent to the current node in the
event flow. | Event | |
|
Returns the string representation of this object, formatted according to locale-specific conventions. | Object | |
|
Returns a string containing all the properties of the Event object. | Event | |
|
Returns the primitive value of the specified object. | Object | |
| Constant | Defined By | ||
|---|---|---|---|
| FLOW_OPERATION_BEGIN : String = "flowOperationBegin" [static]
Defines the value of the type property of a flowOperationBegin event object. | FlowOperationEvent | ||
| FLOW_OPERATION_COMPLETE : String = "flowOperationComplete" [static]
Defines the value of the type property of a flowOperationComplete event object. | FlowOperationEvent | ||
| FLOW_OPERATION_END : String = "flowOperationEnd" [static]
Defines the value of the type property of a flowOperationEnd event object. | FlowOperationEvent | ||
error | property |
error:Error| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
The error thrown, if any, during an operation. If an error occurs during an operation, a reference to the error object is attached to the FLOW_OPERATION_END event. This give you the opportunity to deal with the error before Flash Player throws the error. If you cancel the event, Flash Player will not throw the error.
Implementation
public function get error():Error public function set error(value:Error):voidlevel | property |
operation | property |
operation:FlowOperation| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
The operation that is about to begin or has just ended.
Implementation
public function get operation():FlowOperation public function set operation(value:FlowOperation):voidRelated API Elements
FlowOperationEvent | () | Constructor |
public function FlowOperationEvent(type:String, bubbles:Boolean = false, cancelable:Boolean = false, operation:FlowOperation = null, level:int = 0, error:Error = null)| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
Creates an event object that contains information about a flow operation.
Parameterstype:String — The type of the event. Event listeners can access this information through the
inherited type property. There are two types:
FlowOperationEvent.FLOW_OPERATION_BEGIN;
FlowOperationEvent.FLOW_OPERATION_END.
| |
bubbles:Boolean (default = false) | |
cancelable:Boolean (default = false)Event.preventDefault() method in
your event handler function.
| |
operation:FlowOperation (default = null) | |
level:int (default = 0) | |
error:Error (default = null) |
FLOW_OPERATION_BEGIN | Constant |
public static const FLOW_OPERATION_BEGIN:String = "flowOperationBegin"| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
Defines the value of the type property of a flowOperationBegin event object.
Dispatched before an operation is executed. Cancelling this event blocks the operation.
FLOW_OPERATION_COMPLETE | Constant |
public static const FLOW_OPERATION_COMPLETE:String = "flowOperationComplete"| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
Defines the value of the type property of a flowOperationComplete event object.
Dispatched after all operations including pending and composite operations are completed, composition is finished and the display is scrolled.
FLOW_OPERATION_END | Constant |
public static const FLOW_OPERATION_END:String = "flowOperationEnd"| Language Version: | ActionScript 3.0 |
| Runtime Versions: | Flash Player 10, AIR 1.5 |
Defines the value of the type property of a flowOperationEnd event object.
Dispatched after an operation completes. Any errors are stored in OperationEvent.error.
If there is an error, cancelling this event blocks the rethrow of the error.
Generally speaking all errors are likely to be fatal.
Changing an operation at this time (after it has been executed) may fail.
This example shows how to create an event handler that listens
for the beginning and end of a text flow operation.
The two key steps are to call the addEventListener()
method on the text flow and to create an event handler function.
The call to addEventListener() is made on the TextFlow instance.
You can use the simple string "flowOperationBegin" or "flowOperationEnd",
but it is safer to use the static constant FlowOperationEvent.FLOW_OPERATION_BEGIN
or FlowOperationEvent.FLOW_OPERATION_END, respectively.
The event handler functions in this example are named opBeginHandler()
and opEndHandler().
The opBeginHandler() method uses the trace() function
to produce a trace statement that indicates that a paste operation has started.
The opEndHandler() method also uses the trace() function,
but produces a trace statement only if an error occurs.
package flashx.textLayout.events.examples
{
import flash.display.Sprite;
import flashx.textLayout.compose.StandardFlowComposer;
import flashx.textLayout.container.ContainerController;
import flashx.textLayout.conversion.TextConverter;
import flashx.textLayout.edit.EditManager;
import flashx.textLayout.elements.TextFlow;
import flashx.textLayout.events.FlowOperationEvent;
import flashx.textLayout.operations.FlowOperation;
import flashx.textLayout.operations.PasteOperation;
import flashx.undo.UndoManager;
public class FlowOperationEvent_example extends Sprite
{
private var inputContainer:Sprite;
private var inputTextFlow:TextFlow;
private var inputController:ContainerController;
private var inputEditManager:EditManager;
private var inputUndoManager:UndoManager;
public function FlowOperationEvent_example()
{
var replaceText:String = "paste text here";
inputTextFlow = new TextFlow();
inputContainer = new Sprite();
inputContainer.x = 30;
inputContainer.y = 100;
this.stage.addChild( inputContainer );
inputController = new ContainerController(inputContainer, 225, 20);
inputController.verticalScrollPolicy = flashx.textLayout.container.ScrollPolicy.OFF;
inputTextFlow = TextConverter.importToFlow(replaceText, TextConverter.PLAIN_TEXT_FORMAT);
inputTextFlow.flowComposer = new StandardFlowComposer();
inputTextFlow.flowComposer.addController(inputController);
inputUndoManager = new UndoManager();
inputEditManager = new EditManager(inputUndoManager);
inputTextFlow.interactionManager = inputEditManager;
inputTextFlow.addEventListener(FlowOperationEvent.FLOW_OPERATION_BEGIN, opBeginHandler);
inputTextFlow.addEventListener(FlowOperationEvent.FLOW_OPERATION_END, opEndHandler);
inputTextFlow.flowComposer.updateAllControllers();
}
private function opBeginHandler(evt:FlowOperationEvent):void {
var flowOp:FlowOperation = evt.operation;
if(flowOp is PasteOperation) {
trace("You can cancel or modify the paste operation in this event handler.");
}
}
private function opEndHandler(evt:FlowOperationEvent):void {
var flowOp:FlowOperation = evt.operation;
if(evt.error) {
trace("You can handle the error here and call preventDefault().");
}
}
}
}
Wed Nov 21 2018, 06:34 AM -08:00