QScxmlStateMachine

The QScxmlStateMachine class provides an interface to the state machines created from SCXML files. More

Inheritance diagram of PySide2.QtScxml.QScxmlStateMachine

Synopsis

Functions

Slots

Signals

Static functions

Detailed Description

QScxmlStateMachine is an implementation of the State Chart XML (SCXML) .

All states that are defined in the SCXML file are accessible as properties of QScxmlStateMachine . These properties are boolean values and indicate whether the state is active or inactive.

Note

The QScxmlStateMachine needs a QEventLoop to work correctly. The event loop is used to implement the delay attribute for events and to schedule the processing of a state machine when events are received from nested (or parent) state machines.

class QScxmlStateMachine(metaObject[, parent=None])
Parameters
  • parentQObject

  • metaObjectQMetaObject

PySide2.QtScxml.QScxmlStateMachine.activeStateNames([compress=true])
Parameters

compressbool

Return type

list of strings

Retrieves a list of state names of all active states.

When a state is active, all its parent states are active by definition. When compress is true (the default), the parent states will be filtered out and only the leaf states will be returned. When it is false , the full list of active states will be returned.

PySide2.QtScxml.QScxmlStateMachine.cancelDelayedEvent(sendId)
Parameters

sendId – unicode

Cancels a delayed event with the specified sendId .

PySide2.QtScxml.QScxmlStateMachine.connectToEvent(scxmlEventSpec, receiver, method[, type=Qt.AutoConnection])
Parameters
  • scxmlEventSpec – unicode

  • receiverQObject

  • method – str

  • typeConnectionType

Return type

Connection

PySide2.QtScxml.QScxmlStateMachine.connectToState(scxmlStateName, receiver, method[, type=Qt.AutoConnection])
Parameters
  • scxmlStateName – unicode

  • receiverQObject

  • method – str

  • typeConnectionType

Return type

Connection

PySide2.QtScxml.QScxmlStateMachine.dataModel()
Return type

QScxmlDataModel

Returns the data model used by the state machine.

See also

setDataModel()

PySide2.QtScxml.QScxmlStateMachine.dataModelChanged(model)
Parameters

modelQScxmlDataModel

PySide2.QtScxml.QScxmlStateMachine.finished()
static PySide2.QtScxml.QScxmlStateMachine.fromData(data[, fileName=""])
Parameters
  • dataQIODevice

  • fileName – unicode

Return type

QScxmlStateMachine

Creates a state machine by reading from the QIODevice specified by data .

This method will always return a state machine. If errors occur while reading the SCXML file, fileName , the state machine cannot be started. The errors can be retrieved by calling the parseErrors() method.

See also

parseErrors()

static PySide2.QtScxml.QScxmlStateMachine.fromFile(fileName)
Parameters

fileName – unicode

Return type

QScxmlStateMachine

Creates a state machine from the SCXML file specified by fileName .

This method will always return a state machine. If errors occur while reading the SCXML file, the state machine cannot be started. The errors can be retrieved by calling the parseErrors() method.

See also

parseErrors()

PySide2.QtScxml.QScxmlStateMachine.init()
Return type

bool

Initializes the state machine.

State machine initialization consists of calling setup() , setting the initial values for <data> elements, and executing any <script> tags of the <scxml> tag. The initial data values are taken from the initialValues property.

Returns false if parse errors occur or if any of the initialization steps fail. Returns true otherwise.

PySide2.QtScxml.QScxmlStateMachine.initialValues()
Return type

PySide2.QtScxml.QScxmlStateMachine.initialValuesChanged(initialValues)
Parameters

initialValues

PySide2.QtScxml.QScxmlStateMachine.initializedChanged(initialized)
Parameters

initializedbool

PySide2.QtScxml.QScxmlStateMachine.invokedServices()
Return type

PySide2.QtScxml.QScxmlStateMachine.invokedServicesChanged(invokedServices)
Parameters

invokedServices

PySide2.QtScxml.QScxmlStateMachine.isActive(scxmlStateName)
Parameters

scxmlStateName – unicode

Return type

bool

PySide2.QtScxml.QScxmlStateMachine.isActive(stateIndex)
Parameters

stateIndexint

Return type

bool

Returns true if the state with the ID stateIndex is active.

This method is part of the interface to the compiled representation of SCXML state machines. It should only be used internally and by state machines compiled from SCXML documents.

PySide2.QtScxml.QScxmlStateMachine.isDispatchableTarget(target)
Parameters

target – unicode

Return type

bool

Returns true if a message to target can be dispatched by this state machine.

Valid targets are:

  • #_parent for the parent state machine if the current state machine is started by <invoke>

  • #_internal for the current state machine

  • #_scxml_sessionid, where sessionid is the session ID of the current state machine

  • #_servicename, where servicename is the ID or name of a service started with <invoke> by this state machine

PySide2.QtScxml.QScxmlStateMachine.isInitialized()
Return type

bool

PySide2.QtScxml.QScxmlStateMachine.isInvoked()
Return type

bool

PySide2.QtScxml.QScxmlStateMachine.isRunning()
Return type

bool

Returns true if the state machine is running, false otherwise.

PySide2.QtScxml.QScxmlStateMachine.loader()
Return type

Loader

See also

setLoader()

PySide2.QtScxml.QScxmlStateMachine.loaderChanged(loader)
Parameters

loaderLoader

PySide2.QtScxml.QScxmlStateMachine.log(label, msg)
Parameters
  • label – unicode

  • msg – unicode

PySide2.QtScxml.QScxmlStateMachine.name()
Return type

unicode

PySide2.QtScxml.QScxmlStateMachine.parseErrors()
Return type

PySide2.QtScxml.QScxmlStateMachine.reachedStableState()
PySide2.QtScxml.QScxmlStateMachine.runningChanged(running)
Parameters

runningbool

PySide2.QtScxml.QScxmlStateMachine.sessionId()
Return type

unicode

PySide2.QtScxml.QScxmlStateMachine.setDataModel(model)
Parameters

modelQScxmlDataModel

Sets the data model for this state machine to model . There is a 1:1 relation between state machines and models. After setting the model once you cannot change it anymore. Any further attempts to set the model using this method will be ignored.

See also

dataModel()

PySide2.QtScxml.QScxmlStateMachine.setInitialValues(initialValues)
Parameters

initialValues

See also

initialValues()

PySide2.QtScxml.QScxmlStateMachine.setLoader(loader)
Parameters

loaderLoader

See also

loader()

PySide2.QtScxml.QScxmlStateMachine.setRunning(running)
Parameters

runningbool

Starts the state machine if running is true , or stops it otherwise.

PySide2.QtScxml.QScxmlStateMachine.setTableData(tableData)
Parameters

tableDataQScxmlTableData

See also

tableData()

PySide2.QtScxml.QScxmlStateMachine.start()

Starts this state machine. The machine will reset its configuration and transition to the initial state. When a final top-level state is entered, the machine will emit the finished() signal.

Note

A state machine will not run without a running event loop, such as the main application event loop started with exec() or exec() .

PySide2.QtScxml.QScxmlStateMachine.stateNames([compress=true])
Parameters

compressbool

Return type

list of strings

Retrieves a list of state names of all states.

When compress is true (the default), the states that contain child states will be filtered out and only the leaf states will be returned. When it is false , the full list of all states will be returned.

The returned list does not contain the states of possible nested state machines.

Note

The order of the state names in the list is the order in which the states occurred in the SCXML document.

PySide2.QtScxml.QScxmlStateMachine.stop()

Stops this state machine. The machine will not execute any further state transitions. Its running property is set to false .

PySide2.QtScxml.QScxmlStateMachine.submitEvent(event)
Parameters

eventQScxmlEvent

Submits the SCXML event event to the internal or external event queue depending on the priority of the event.

When a delay is set, the event will be queued for delivery after the timeout has passed. The state machine takes ownership of event and deletes it after processing.

PySide2.QtScxml.QScxmlStateMachine.submitEvent(eventName)
Parameters

eventName – unicode

PySide2.QtScxml.QScxmlStateMachine.submitEvent(eventName, data)
Parameters
  • eventName – unicode

  • data – object

A utility method to create and submit an external event with the specified eventName as the name and data as the payload data.

PySide2.QtScxml.QScxmlStateMachine.tableData()
Return type

QScxmlTableData

See also

setTableData()

PySide2.QtScxml.QScxmlStateMachine.tableDataChanged(tableData)
Parameters

tableDataQScxmlTableData