| Package | org.spicefactory.lib.task |
| Class | public class Task |
| Inheritance | Task  flash.events.EventDispatcher |
| Subclasses | CleanUpChessPieceTask, CleanUpPiecesBitboardTask, DelegateTask, ResultTask, SynchronousDelegateTask, TaskGroup |
START, SUSPEND, RESUME,
CANCEL, COMPLETE and ERROR), multiple Tasks can be
chained in a SequentialTaskGroup or executed concurrently in a
ConcurrentTaskGroup. Both classes fire their COMPLETE event when all
their child Tasks have completed and both extend the abstract TaskGroup class.
Since TaskGroup is a subclass of Task itself,
it can be nested too. This type of nesting can be cumbersome to implement without Tasks
if you work with a lot of different types of asynchronous operations which all have
their individual event sets for notifying observers that they have completed or that an
error occured.
A minimal subclass of Task would
at least overwrite the doStart method, do its work and then call complete
when the operation is done. The Task class comes with several properties to control
the behaviour. A Task can be restartable or cancelable, if
the suspendable property is true, a Task can be suspended and resumed.
If the skippable property is set, a Task can be forced to move to its
final state (which may make sense in asynchronous operations like animations, but
obviously not in Tasks like loading operations). All these properties are true by
default and are protected so they must be set by subclasses.
| Property | Defined By | ||
|---|---|---|---|
| cancelable : Boolean [read-only]
Indicates whether this Task can be cancelled. | Task | ||
| data : *
An arbitrary value associated with this Task. | Task | ||
| parent : TaskGroup [read-only]
The parent of this Task. | Task | ||
| restartable : Boolean [read-only]
Indicates whether this Task can be restarted. | Task | ||
| root : Task [read-only]
The root TaskGroup in case this Task is nested in one or more TaskGroups. | Task | ||
| skippable : Boolean [read-only]
Indicates whether this Task can be forced to skip to its final state. | Task | ||
| state : TaskState [read-only]
The current state of this Task. | Task | ||
| suspendable : Boolean [read-only]
Indicates whether this Task can be suspended. | Task | ||
| timeout : uint [read-only]
The timeout for this Task in milliseconds. | Task | ||
| Method | Defined By | ||
|---|---|---|---|
cancel():Boolean
Cancels this Task. | Task | ||
resume():Boolean
Resumes this Task if it is suspended. | Task | ||
skip():Boolean
Forces this Task to move to its final state. | Task | ||
start():Boolean
Starts this Task. | Task | ||
suspend():Boolean
Suspends this Task. | Task | ||
| Method | Defined By | ||
|---|---|---|---|
complete():Boolean
Signals that this Task has completed. | Task | ||
doCancel():void
Called before the CANCEL event gets fired. | Task | ||
doError(message:String):void
Called before the ERROR event gets fired. | Task | ||
doResume():void
Called before the RESUME event gets fired. | Task | ||
doSkip():void
Called after skip has been called but before the COMPLETE event gets fired. | Task | ||
doStart():void
Called before the START event gets fired. | Task | ||
doSuspend():void
Called before the SUSPEND event gets fired. | Task | ||
doTimeout():void
Called before the ERROR event gets fired after a timeout occurred. | Task | ||
error(message:String):Boolean
Signals an error condition and cancels the Task. | Task | ||
setCancelable(value:Boolean):void
Specifies whether this Task can be cancelled. | Task | ||
setName(name:String):void
Sets the name of this Task. | Task | ||
setRestartable(value:Boolean):void
Specifies whether this Task can be restarted. | Task | ||
setSkippable(value:Boolean):void
Specifies whether this Task can be forced to skip to its final state. | Task | ||
setSuspendable(value:Boolean):void
Specifies whether this Task can be suspended. | Task | ||
setTimeout(value:uint):void
Sets the timeout for this Task in milliseconds. | Task | ||
| Event | Summary | Defined By | ||
|---|---|---|---|---|
| Dispatched when a Task is cancelled. | Task | |||
| Dispatched when a Task has completed its execution. | Task | |||
| Dispatched when a Task has aborted due to an error condition. | Task | |||
| Dispatched when a suspended Task is resumed. | Task | |||
| Dispatched when a Task is started. | Task | |||
| Dispatched when a Task is suspended. | Task | |||
| cancelable | property |
cancelable:Boolean [read-only] Indicates whether this Task can be cancelled.
public function get cancelable():Boolean| data | property |
data:*
An arbitrary value associated with this Task.
This may be useful if a Task is nested in a TaskGroup
for example and produces or loads data that is needed by subsequent Tasks.
If the value for this Task is null and the Task has a parent, the
parents data value will be used.
public function get data():* public function set data(value:any):void| parent | property |
parent:TaskGroup [read-only]
The parent of this Task. The value is null if this Task is not nested
in a TaskGroup.
public function get parent():TaskGroup| restartable | property |
restartable:Boolean [read-only]
Indicates whether this Task can be restarted. If true the start
method can be invoked again after either the COMPLETE, CANCEL
or ERROR events were fired. If it is false calling start after
these event were fired will cause an Error to be thrown.
public function get restartable():Boolean| root | property |
root:Task [read-only] The root TaskGroup in case this Task is nested in one or more TaskGroups. If this Task is not nested then this property points to the Task itself.
public function get root():Task| skippable | property |
skippable:Boolean [read-only]
Indicates whether this Task can be forced to skip to its final state.
This may be useful in asynchronous operations like animations, but
not in Tasks like loading operations. For the difference between
cancelable and skippable see
skip().
public function get skippable():Boolean| state | property |
state:TaskState [read-only] The current state of this Task.
public function get state():TaskState| suspendable | property |
suspendable:Boolean [read-only] Indicates whether this Task can be suspended.
public function get suspendable():Boolean| timeout | property |
timeout:uint [read-only] The timeout for this Task in milliseconds. A value of 0 disables the timeout.
public function get timeout():uint| cancel | () | method |
public function cancel():Boolean
Cancels this Task. For this method to succeed the cancelable property of this Task
must be set to true and the current state of the Task must be ACTIVE or
SUSPENDED.
If this method executes successfully the CANCEL event will be fired.
Boolean — true if the Task successfully switched its internal state, false if otherwise
|
| complete | () | method |
protected function complete():Boolean
Signals that this Task has completed. Subclasses should call this method
when the asynchronous operation has completed. If this method executes successfully
the COMPLETE event will be fired.
Boolean — true if the Task successfully switched its internal state, false if otherwise
|
| doCancel | () | method |
protected function doCancel():void
Called before the CANCEL event gets fired.
Subclasses for cancelable Tasks should overwrite this method and cancel the actual operation
this Task performs.
| doError | () | method |
protected function doError(message:String):void
Called before the ERROR event gets fired.
Subclasses may optionally overwrite this method to do some cleanup.
Parameters
message:String |
| doResume | () | method |
protected function doResume():void
Called before the RESUME event gets fired.
Subclasses for suspendable Tasks should overwrite this method and resume the suspended operation
this Task performs.
| doSkip | () | method |
protected function doSkip():void
Called after skip has been called but before the COMPLETE event gets fired.
Subclasses for skippable Tasks should overwrite this method and put this Task
into its final state.
| doStart | () | method |
protected function doStart():void
Called before the START event gets fired.
Subclasses should overwrite this method to start with the actual operation
this Task should perform.
| doSuspend | () | method |
protected function doSuspend():void
Called before the SUSPEND event gets fired.
Subclasses for suspendable Tasks should overwrite this method and suspend the actual operation
this Task performs.
| doTimeout | () | method |
protected function doTimeout():void
Called before the ERROR event gets fired after a timeout occurred.
Subclasses should overwrite this method and cancel the operation this Task performs.
In many cases this method can be handled the same way like the doCancel hook.
| error | () | method |
protected function error(message:String):Boolean
Signals an error condition and cancels the Task. Subclasses should call this method
when the asynchronous operation cannot be successfully completed.
If this method executes successfully the ERROR event will be fired.
Parameters
message:String — the error description
|
Boolean — true if the Task successfully switched its internal state, false if otherwise
|
| resume | () | method |
public function resume():Boolean
Resumes this Task if it is suspended. For this method to succeed the suspendable property of this Task
must be set to true and the current state of the Task must be SUSPENDED.
If this Task is member of a TaskGroup it cannot
be resumed if the parent TaskGroup is still suspended.
If this method executes successfully the RESUME event will be fired.
Boolean — true if the Task successfully switched its internal state, false if otherwise
|
| setCancelable | () | method |
protected function setCancelable(value:Boolean):voidSpecifies whether this Task can be cancelled.
Parameters
value:Boolean — whether this Task can be cancelled
|
| setName | () | method |
protected function setName(name:String):voidSets the name of this Task. This name will not be used internally by the Task Framework except for log output.
Parameters
name:String — the new name of this Task
|
| setRestartable | () | method |
protected function setRestartable(value:Boolean):void
Specifies whether this Task can be restarted. If true the start
method can be invoked again after either the COMPLETE, CANCEL
or ERROR events were fired. If it is false calling start after
these event were fired will cause an Error to be thrown.
Parameters
value:Boolean — whether this Task can be restarted
|
| setSkippable | () | method |
protected function setSkippable(value:Boolean):voidSpecifies whether this Task can be forced to skip to its final state. This may be useful in asynchronous operations like animations, but not in Tasks like loading operations.
Parameters
value:Boolean — whether this Task can be forced to skip/move to its final state
|
| setSuspendable | () | method |
protected function setSuspendable(value:Boolean):voidSpecifies whether this Task can be suspended.
Parameters
value:Boolean — whether this Task can be suspended
|
| setTimeout | () | method |
protected function setTimeout(value:uint):voidSets the timeout for this Task in milliseconds. A value of 0 disables the timeout.
Parameters
value:uint — the timeout for this Task in milliseconds
|
| skip | () | method |
public function skip():Boolean
Forces this Task to move to its final state.
If this method executes successfully the COMPLETE event will be fired.
The method is somewhat similar to the cancel method but with a few subtle
differences:
cancel would imply that the asynchronous operation just aborts
and optionally rewinds to its initial state. In constrast the semantics of skip
would rather imply to move the operation to its final state and skip the remaining progress.
This is applicable for operations like animations, but
obviously not feasible in Tasks like loading operations.cancel method would cause a
CANCEL event to be fired, while the skip method would just cause a
COMPLETE event to be fired as if the Task completed normally.Boolean — true if the Task successfully switched its internal state, false if otherwise
|
| start | () | method |
public function start():BooleanStarts this Task. If this Task is member of a TaskGroup this method should not be called by application code.
ReturnsBoolean — true if the Task was started successfully, false if it was in an illegal state
|
| suspend | () | method |
public function suspend():Boolean
Suspends this Task. For this method to succeed the suspendable property of this Task
must be set to true and the current state of the Task must be ACTIVE.
If this method executes successfully the SUSPEND event will be fired.
Boolean — true if the Task successfully switched its internal state, false if otherwise
|
| cancel | Event |
org.spicefactory.lib.task.events.TaskEventorg.spicefactory.lib.task.events.TaskEvent.CANCELDispatched when a Task is cancelled.
Constant for the type of event fired when a Task is cancelled.| complete | Event |
org.spicefactory.lib.task.events.TaskEventorg.spicefactory.lib.task.events.TaskEvent.COMPLETEDispatched when a Task has completed its execution.
Constant for the type of event fired when a Task is completed.| error | Event |
flash.events.ErrorEventflash.events.ErrorEvent.ERRORDispatched when a Task has aborted due to an error condition.
| resume | Event |
org.spicefactory.lib.task.events.TaskEventorg.spicefactory.lib.task.events.TaskEvent.RESUMEDispatched when a suspended Task is resumed.
Constant for the type of event fired when a Task is resumed.| start | Event |
org.spicefactory.lib.task.events.TaskEventorg.spicefactory.lib.task.events.TaskEvent.STARTDispatched when a Task is started.
Constant for the type of event fired when a Task is started.| suspend | Event |
org.spicefactory.lib.task.events.TaskEventorg.spicefactory.lib.task.events.TaskEvent.SUSPENDDispatched when a Task is suspended.
Constant for the type of event fired when a Task is suspended.