FallbackChainState Class Reference

#include <FallbackChainState.h>

Inheritance diagram for FallbackChainState:

Collaboration diagram for FallbackChainState:

Classes
struct	StrategyEntry

Public Types
using	Strategy = std::function< bool()>
	Strategy action - returns true on success.
Public Types inherited from QGCAbstractState
using	EntryCallback = std::function< void()>
using	ExitCallback = std::function< void()>
using	EventHandler = std::function< bool(QEvent *)>

Signals
void	tryingStrategy (const QString &name, int index, int total)
	Emitted when trying a strategy.
void	strategyFailed (const QString &name)
	Emitted when a strategy fails and moving to next.
void	strategySucceeded (const QString &name)
	Emitted when a strategy succeeds.
Signals inherited from QGCAbstractState
void	advance ()
void	error ()

Public Member Functions
	FallbackChainState (const QString &stateName, QState *parent)
void	addStrategy (const QString &name, Strategy action)
QString	successfulStrategy () const
	Get the name of the strategy that succeeded.
int	currentStrategyIndex () const
	Get the current strategy index being tried.
int	strategyCount () const
	Get the total number of strategies.
Public Member Functions inherited from QGCState
	QGCState (const QString &stateName, QState *parentState)
template<typename PointerToMemberFunction >
QSignalTransition *	addThisTransition (PointerToMemberFunction signal, QAbstractState *target)
	Simpler version of QState::addTransition which assumes the sender is this.
void	setLocalErrorState (QAbstractState *errorState)
QAbstractState *	localErrorState () const
	Get the per-state error state (nullptr if using global)
void	setProperty (QObject *object, const char *name, const QVariant &value)
void	setEnabled (QObject *object, bool enabled)
	Convenience overload for setting enabled state on widgets/controls.
void	setVisible (QObject *object, bool visible)
	Convenience overload for setting visible state on widgets/controls.
Public Member Functions inherited from QGCAbstractState
	QGCAbstractState (const QString &stateName, QState *parent)
QGCStateMachine *	machine () const
Vehicle *	vehicle () const
QString	stateName () const
class StateContext *	context () const
void	setOnEntry (EntryCallback callback)
	Set a callback to be invoked when the state is entered.
void	setOnExit (ExitCallback callback)
	Set a callback to be invoked when the state is exited.
void	setCallbacks (EntryCallback onEntry, ExitCallback onExit=nullptr)
	Set both entry and exit callbacks.
void	setEventHandler (EventHandler handler)
	Set a custom event handler for this state.

Protected Member Functions
void	onEnter () override
	Override to perform actions on state entry.
Protected Member Functions inherited from QGCAbstractState
virtual void	onLeave ()
	Override to perform actions on state exit.
void	onEntry (QEvent *event) override
void	onExit (QEvent *event) override
bool	event (QEvent *event) override

Detailed Description

A state that tries multiple strategies in order until one succeeds.

Strategies are executed in the order they were added. If a strategy succeeds, the state emits advance(). If all strategies fail, error() is emitted.

Example usage:

auto* state = new FallbackChainState("Connect", &machine);
state->addStrategy("Primary", []() { return connectPrimary(); });
state->addStrategy("Backup", []() { return connectBackup(); });
state->addStrategy("Offline", []() { return goOffline(); });
 
state->addTransition(state, &FallbackChainState::advance, connectedState);
state->addTransition(state, &FallbackChainState::error, failedState);

Definition at line 22 of file FallbackChainState.h.

Member Typedef Documentation

Strategy

using FallbackChainState::Strategy = std::function<bool()>

Strategy action - returns true on success.

Definition at line 29 of file FallbackChainState.h.

Constructor & Destructor Documentation

FallbackChainState()

FallbackChainState::FallbackChainState	(	const QString &	stateName,
		QState *	parent
	)

Definition at line 4 of file FallbackChainState.cc.

Member Function Documentation

addStrategy()

void FallbackChainState::addStrategy	(	const QString &	name,
		Strategy	action
	)

Add a strategy to the chain

Parameters

name	Strategy name for logging
action	Strategy action (returns true on success)

Definition at line 9 of file FallbackChainState.cc.

currentStrategyIndex()

int FallbackChainState::currentStrategyIndex ( ) const

inline

Get the current strategy index being tried.

Definition at line 47 of file FallbackChainState.h.

onEnter()

void FallbackChainState::onEnter ( )

overrideprotectedvirtual

Override to perform actions on state entry.

Reimplemented from QGCAbstractState.

Definition at line 14 of file FallbackChainState.cc.

strategyCount()

int FallbackChainState::strategyCount ( ) const

inline

Get the total number of strategies.

Definition at line 50 of file FallbackChainState.h.

strategyFailed

void FallbackChainState::strategyFailed ( const QString &  name )

signal

Emitted when a strategy fails and moving to next.

strategySucceeded

void FallbackChainState::strategySucceeded ( const QString &  name )

signal

Emitted when a strategy succeeds.

successfulStrategy()

QString FallbackChainState::successfulStrategy ( ) const

inline

Get the name of the strategy that succeeded.

Definition at line 44 of file FallbackChainState.h.

tryingStrategy

void FallbackChainState::tryingStrategy ( const QString &  name, int  index, int  total  )

signal

Emitted when trying a strategy.

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The documentation for this class was generated from the following files:

• src/Utilities/StateMachine/States/FallbackChainState.h
• src/Utilities/StateMachine/States/FallbackChainState.cc