The scheduler responsible for running Commands. More...

#include <frc2/command/CommandScheduler.h>

Inheritance diagram for frc2::CommandScheduler:

Public Types
using	Action = std::function< void(const Command &)>

using	InterruptAction = std::function< void(const Command &, const std::optional< Command * > &)>

Public Member Functions
	~CommandScheduler () override

	CommandScheduler (const CommandScheduler &)=delete

CommandScheduler &	operator= (const CommandScheduler &)=delete

void	SetPeriod (units::second_t period)
	Changes the period of the loop overrun watchdog. More...

frc::EventLoop *	GetActiveButtonLoop () const
	Get the active button poll. More...

void	SetActiveButtonLoop (frc::EventLoop *loop)
	Replace the button poll with another one. More...

frc::EventLoop *	GetDefaultButtonLoop () const
	Get the default button poll. More...

void	Schedule (const CommandPtr &command)
	Schedules a command for execution. More...

void	Schedule (Command *command)
	Schedules a command for execution. More...

void	Schedule (std::span< Command *const > commands)
	Schedules multiple commands for execution. More...

void	Schedule (std::initializer_list< Command * > commands)
	Schedules multiple commands for execution. More...

void	Run ()
	Runs a single iteration of the scheduler. More...

void	RegisterSubsystem (Subsystem *subsystem)
	Registers subsystems with the scheduler. More...

void	UnregisterSubsystem (Subsystem *subsystem)
	Un-registers subsystems with the scheduler. More...

void	RegisterSubsystem (std::initializer_list< Subsystem * > subsystems)

void	RegisterSubsystem (std::span< Subsystem *const > subsystems)

void	UnregisterSubsystem (std::initializer_list< Subsystem * > subsystems)

void	UnregisterSubsystem (std::span< Subsystem *const > subsystems)

void	UnregisterAllSubsystems ()
	Un-registers all registered Subsystems with the scheduler. More...

template<std::derived_from< Command > T>
void	SetDefaultCommand (Subsystem *subsystem, T &&defaultCommand)
	Sets the default command for a subsystem. More...

void	SetDefaultCommand (Subsystem *subsystem, CommandPtr &&defaultCommand)
	Sets the default command for a subsystem. More...

void	RemoveDefaultCommand (Subsystem *subsystem)
	Removes the default command for a subsystem. More...

Command *	GetDefaultCommand (const Subsystem *subsystem) const
	Gets the default command associated with this subsystem. More...

void	Cancel (Command *command)
	Cancels commands. More...

void	Cancel (const CommandPtr &command)
	Cancels commands. More...

void	Cancel (std::span< Command *const > commands)
	Cancels commands. More...

void	Cancel (std::initializer_list< Command * > commands)
	Cancels commands. More...

void	CancelAll ()
	Cancels all commands that are currently scheduled. More...

bool	IsScheduled (std::span< const Command *const > commands) const
	Whether the given commands are running. More...

bool	IsScheduled (std::initializer_list< const Command * > commands) const
	Whether the given commands are running. More...

bool	IsScheduled (const Command *command) const
	Whether a given command is running. More...

bool	IsScheduled (const CommandPtr &command) const
	Whether a given command is running. More...

Command *	Requiring (const Subsystem *subsystem) const
	Returns the command currently requiring a given subsystem. More...

void	Disable ()
	Disables the command scheduler. More...

void	Enable ()
	Enables the command scheduler. More...

void	OnCommandInitialize (Action action)
	Adds an action to perform on the initialization of any command by the scheduler. More...

void	OnCommandExecute (Action action)
	Adds an action to perform on the execution of any command by the scheduler. More...

void	OnCommandInterrupt (Action action)
	Adds an action to perform on the interruption of any command by the scheduler. More...

void	OnCommandInterrupt (InterruptAction action)
	Adds an action to perform on the interruption of any command by the scheduler. More...

void	OnCommandFinish (Action action)
	Adds an action to perform on the finishing of any command by the scheduler. More...

void	RequireUngrouped (const Command *command)
	Requires that the specified command hasn't already been added to a composition. More...

void	RequireUngrouped (std::span< const std::unique_ptr< Command > > commands)
	Requires that the specified commands have not already been added to a composition. More...

void	RequireUngrouped (std::initializer_list< const Command * > commands)
	Requires that the specified commands have not already been added to a composition. More...

void	RequireUngroupedAndUnscheduled (const Command *command)
	Requires that the specified command has not already been added to a composition and is not currently scheduled. More...

void	RequireUngroupedAndUnscheduled (std::span< const std::unique_ptr< Command > > commands)
	Requires that the specified commands have not already been added to a composition and are not currently scheduled. More...

void	RequireUngroupedAndUnscheduled (std::initializer_list< const Command * > commands)
	Requires that the specified commands have not already been added to a composition and are not currently scheduled. More...

void	InitSendable (wpi::SendableBuilder &builder) override
	Initializes this Sendable object. More...

Public Member Functions inherited from wpi::Sendable
virtual	~Sendable ()=default

virtual void	InitSendable (SendableBuilder &builder)=0
	Initializes this Sendable object. More...

Public Member Functions inherited from wpi::SendableHelper< CommandScheduler >
	SendableHelper (const SendableHelper &rhs)=default

	SendableHelper (SendableHelper &&rhs)

SendableHelper &	operator= (const SendableHelper &rhs)=default

SendableHelper &	operator= (SendableHelper &&rhs)

Static Public Member Functions
static CommandScheduler &	GetInstance ()
	Returns the Scheduler instance. More...

Friends
class	CommandTestBase

template<typename T >
class	CommandTestBaseWithParam

Additional Inherited Members
Protected Member Functions inherited from wpi::SendableHelper< CommandScheduler >
	SendableHelper ()=default

	~SendableHelper ()

Detailed Description

The scheduler responsible for running Commands.

A Command-based robot should call Run() on the singleton instance in its periodic block in order to run commands synchronously from the main loop. Subsystems should be registered with the scheduler using RegisterSubsystem() in order for their Periodic() methods to be called and for their default commands to be scheduled.

This class is provided by the NewCommands VendorDep

Member Typedef Documentation

◆ Action

using frc2::CommandScheduler::Action = std::function<void(const Command&)>

◆ InterruptAction

using frc2::CommandScheduler::InterruptAction = std::function<void(const Command&, const std::optional<Command*>&)>

Constructor & Destructor Documentation

◆ ~CommandScheduler()

frc2::CommandScheduler::~CommandScheduler ( )

override

◆ CommandScheduler()

frc2::CommandScheduler::CommandScheduler ( const CommandScheduler & )

delete

Member Function Documentation

◆ Cancel() [1/4]

void frc2::CommandScheduler::Cancel ( Command * command )

Cancels commands.

The scheduler will only call Command::End() method of the canceled command with true, indicating they were canceled (as opposed to finishing normally).

Commands will be canceled even if they are not scheduled as interruptible.

Parameters

command the command to cancel

◆ Cancel() [2/4]

void frc2::CommandScheduler::Cancel ( const CommandPtr & command )

Cancels commands.

The scheduler will only call Command::End() method of the canceled command with true, indicating they were canceled (as opposed to finishing normally).

Commands will be canceled even if they are not scheduled as interruptible.

Parameters

command the command to cancel

◆ Cancel() [3/4]

void frc2::CommandScheduler::Cancel ( std::initializer_list< Command * > commands )

Cancels commands.

The scheduler will only call Command::End() method of the canceled command with true, indicating they were canceled (as opposed to finishing normally).

Commands will be canceled even if they are not scheduled as interruptible.

Parameters

commands the commands to cancel

◆ Cancel() [4/4]

void frc2::CommandScheduler::Cancel ( std::span< Command *const > commands )

Cancels commands.

The scheduler will only call Command::End() method of the canceled command with true, indicating they were canceled (as opposed to finishing normally).

Commands will be canceled even if they are not scheduled as interruptible.

Parameters

commands the commands to cancel

◆ CancelAll()

void frc2::CommandScheduler::CancelAll ( )

Cancels all commands that are currently scheduled.

◆ Disable()

void frc2::CommandScheduler::Disable ( )

Disables the command scheduler.

◆ Enable()

void frc2::CommandScheduler::Enable ( )

Enables the command scheduler.

◆ GetActiveButtonLoop()

frc::EventLoop * frc2::CommandScheduler::GetActiveButtonLoop ( ) const

Get the active button poll.

Returns: a reference to the current frc::EventLoop object polling buttons.

◆ GetDefaultButtonLoop()

frc::EventLoop * frc2::CommandScheduler::GetDefaultButtonLoop ( ) const

Get the default button poll.

Returns: a reference to the default frc::EventLoop object polling buttons.

◆ GetDefaultCommand()

Command * frc2::CommandScheduler::GetDefaultCommand ( const Subsystem * subsystem ) const

Gets the default command associated with this subsystem.

Null if this subsystem has no default command associated with it.

Parameters

subsystem the subsystem to inquire about

Returns: the default command associated with the subsystem

◆ GetInstance()

static CommandScheduler & frc2::CommandScheduler::GetInstance ( )

static

Returns the Scheduler instance.

Returns: the instance

◆ InitSendable()

void frc2::CommandScheduler::InitSendable ( wpi::SendableBuilder & builder )

overridevirtual

Initializes this Sendable object.

Parameters

builder sendable builder

Implements wpi::Sendable.

◆ IsScheduled() [1/4]

bool frc2::CommandScheduler::IsScheduled ( const Command * command ) const

Whether a given command is running.

Note that this only works on commands that are directly scheduled by the scheduler; it will not work on commands inside of CommandGroups, as the scheduler does not see them.

Parameters

command the command to query

Returns: whether the command is currently scheduled

◆ IsScheduled() [2/4]

bool frc2::CommandScheduler::IsScheduled ( const CommandPtr & command ) const

Whether a given command is running.

Note that this only works on commands that are directly scheduled by the scheduler; it will not work on commands inside of CommandGroups, as the scheduler does not see them.

Parameters

command the command to query

Returns: whether the command is currently scheduled

◆ IsScheduled() [3/4]

bool frc2::CommandScheduler::IsScheduled ( std::initializer_list< const Command * > commands ) const

Whether the given commands are running.

Note that this only works on commands that are directly scheduled by the scheduler; it will not work on commands inside of CommandGroups, as the scheduler does not see them.

Parameters

commands the command to query

Returns: whether the command is currently scheduled

◆ IsScheduled() [4/4]

bool frc2::CommandScheduler::IsScheduled ( std::span< const Command *const > commands ) const

Whether the given commands are running.

Note that this only works on commands that are directly scheduled by the scheduler; it will not work on commands inside of CommandGroups, as the scheduler does not see them.

Parameters

commands the command to query

Returns: whether the command is currently scheduled

◆ OnCommandExecute()

void frc2::CommandScheduler::OnCommandExecute ( Action action )

Adds an action to perform on the execution of any command by the scheduler.

Parameters

action the action to perform

◆ OnCommandFinish()

void frc2::CommandScheduler::OnCommandFinish ( Action action )

Adds an action to perform on the finishing of any command by the scheduler.

Parameters

action the action to perform

◆ OnCommandInitialize()

void frc2::CommandScheduler::OnCommandInitialize ( Action action )

Adds an action to perform on the initialization of any command by the scheduler.

Parameters

action the action to perform

◆ OnCommandInterrupt() [1/2]

void frc2::CommandScheduler::OnCommandInterrupt ( Action action )

Adds an action to perform on the interruption of any command by the scheduler.

Parameters

action the action to perform

◆ OnCommandInterrupt() [2/2]

void frc2::CommandScheduler::OnCommandInterrupt ( InterruptAction action )

Adds an action to perform on the interruption of any command by the scheduler.

The action receives the interrupted command and an optional containing the interrupting command, or nullopt if it was not canceled by a command (e.g., by Cancel()).

Parameters

action the action to perform

◆ operator=()

CommandScheduler & frc2::CommandScheduler::operator= ( const CommandScheduler & )

delete

◆ RegisterSubsystem() [1/3]

void frc2::CommandScheduler::RegisterSubsystem ( std::initializer_list< Subsystem * > subsystems )

◆ RegisterSubsystem() [2/3]

void frc2::CommandScheduler::RegisterSubsystem ( std::span< Subsystem *const > subsystems )

◆ RegisterSubsystem() [3/3]

void frc2::CommandScheduler::RegisterSubsystem ( Subsystem * subsystem )

Registers subsystems with the scheduler.

This must be called for the subsystem's periodic block to run when the scheduler is run, and for the subsystem's default command to be scheduled. It is recommended to call this from the constructor of your subsystem implementations.

Parameters

subsystem the subsystem to register

◆ RemoveDefaultCommand()

void frc2::CommandScheduler::RemoveDefaultCommand ( Subsystem * subsystem )

Removes the default command for a subsystem.

The current default command will run until another command is scheduled that requires the subsystem, at which point the current default command will not be re-scheduled.

Parameters

subsystem the subsystem whose default command will be removed

◆ RequireUngrouped() [1/3]

void frc2::CommandScheduler::RequireUngrouped ( const Command * command )

Requires that the specified command hasn't already been added to a composition.

Parameters

command The command to check

Exceptions

if	the given commands have already been composed.

◆ RequireUngrouped() [2/3]

void frc2::CommandScheduler::RequireUngrouped ( std::initializer_list< const Command * > commands )

Requires that the specified commands have not already been added to a composition.

Parameters

commands The commands to check

Exceptions

IllegalArgumentException if the given commands have already been composed.

◆ RequireUngrouped() [3/3]

void frc2::CommandScheduler::RequireUngrouped ( std::span< const std::unique_ptr< Command > > commands )

Requires that the specified commands have not already been added to a composition.

Parameters

commands The commands to check

Exceptions

if	the given commands have already been composed.

◆ RequireUngroupedAndUnscheduled() [1/3]

void frc2::CommandScheduler::RequireUngroupedAndUnscheduled ( const Command * command )

Requires that the specified command has not already been added to a composition and is not currently scheduled.

Parameters

command The command to check

Exceptions

IllegalArgumentException if the given command has already been composed or scheduled.

◆ RequireUngroupedAndUnscheduled() [2/3]

void frc2::CommandScheduler::RequireUngroupedAndUnscheduled ( std::initializer_list< const Command * > commands )

Requires that the specified commands have not already been added to a composition and are not currently scheduled.

Parameters

commands The commands to check

Exceptions

IllegalArgumentException if the given commands have already been composed or scheduled.

◆ RequireUngroupedAndUnscheduled() [3/3]

void frc2::CommandScheduler::RequireUngroupedAndUnscheduled ( std::span< const std::unique_ptr< Command > > commands )

Requires that the specified commands have not already been added to a composition and are not currently scheduled.

Parameters

commands The commands to check

Exceptions

IllegalArgumentException if the given commands have already been composed.

◆ Requiring()

Command * frc2::CommandScheduler::Requiring ( const Subsystem * subsystem ) const

Returns the command currently requiring a given subsystem.

Null if no command is currently requiring the subsystem

Parameters

subsystem the subsystem to be inquired about

Returns: the command currently requiring the subsystem

◆ Run()

void frc2::CommandScheduler::Run ( )

Runs a single iteration of the scheduler.

The execution occurs in the following order:

Subsystem periodic methods are called.

Button bindings are polled, and new commands are scheduled from them.

Currently-scheduled commands are executed.

End conditions are checked on currently-scheduled commands, and commands that are finished have their end methods called and are removed.

Any subsystems not being used as requirements have their default methods started.

◆ Schedule() [1/4]

void frc2::CommandScheduler::Schedule ( Command * command )

Schedules a command for execution.

Does nothing if the command is already scheduled. If a command's requirements are not available, it will only be started if all the commands currently using those requirements have been scheduled as interruptible. If this is the case, they will be interrupted and the command will be scheduled.

Parameters

command the command to schedule

◆ Schedule() [2/4]

void frc2::CommandScheduler::Schedule ( const CommandPtr & command )

Schedules a command for execution.

Does nothing if the command is already scheduled. If a command's requirements are not available, it will only be started if all the commands currently using those requirements are interruptible. If this is the case, they will be interrupted and the command will be scheduled.

Parameters

command the command to schedule

◆ Schedule() [3/4]

void frc2::CommandScheduler::Schedule ( std::initializer_list< Command * > commands )

Schedules multiple commands for execution.

Does nothing for commands already scheduled.

Parameters

commands the commands to schedule

◆ Schedule() [4/4]

void frc2::CommandScheduler::Schedule ( std::span< Command *const > commands )

Schedules multiple commands for execution.

Does nothing for commands already scheduled.

Parameters

commands the commands to schedule

◆ SetActiveButtonLoop()

void frc2::CommandScheduler::SetActiveButtonLoop ( frc::EventLoop * loop )

Replace the button poll with another one.

Parameters

loop	the new button polling loop object.

◆ SetDefaultCommand() [1/2]

void frc2::CommandScheduler::SetDefaultCommand	(	Subsystem *	subsystem,
		CommandPtr &&	defaultCommand
	)

Sets the default command for a subsystem.

Registers that subsystem if it is not already registered. Default commands will run whenever there is no other command currently scheduled that requires the subsystem. Default commands should be written to never end (i.e. their IsFinished() method should return false), as they would simply be re-scheduled if they do. Default commands must also require their subsystem.

Parameters

subsystem	the subsystem whose default command will be set
defaultCommand	the default command to associate with the subsystem

◆ SetDefaultCommand() [2/2]

template<std::derived_from< Command > T>

void frc2::CommandScheduler::SetDefaultCommand	(	Subsystem *	subsystem,
		T &&	defaultCommand
	)

inline

Sets the default command for a subsystem.

Registers that subsystem if it is not already registered. Default commands will run whenever there is no other command currently scheduled that requires the subsystem. Default commands should be written to never end (i.e. their IsFinished() method should return false), as they would simply be re-scheduled if they do. Default commands must also require their subsystem.

Parameters

subsystem	the subsystem whose default command will be set
defaultCommand	the default command to associate with the subsystem

◆ SetPeriod()

void frc2::CommandScheduler::SetPeriod ( units::second_t period )

Changes the period of the loop overrun watchdog.

This should be kept in sync with the TimedRobot period.

◆ UnregisterAllSubsystems()

void frc2::CommandScheduler::UnregisterAllSubsystems ( )

Un-registers all registered Subsystems with the scheduler.

All currently registered subsystems will no longer have their periodic block called, and will not have their default command scheduled.

◆ UnregisterSubsystem() [1/3]

void frc2::CommandScheduler::UnregisterSubsystem ( std::initializer_list< Subsystem * > subsystems )

◆ UnregisterSubsystem() [2/3]

void frc2::CommandScheduler::UnregisterSubsystem ( std::span< Subsystem *const > subsystems )

◆ UnregisterSubsystem() [3/3]

void frc2::CommandScheduler::UnregisterSubsystem ( Subsystem * subsystem )

Un-registers subsystems with the scheduler.

The subsystem will no longer have its periodic block called, and will not have its default command scheduled.

Parameters

subsystem the subsystem to un-register

Friends And Related Function Documentation

◆ CommandTestBase

friend class CommandTestBase

friend

◆ CommandTestBaseWithParam

template<typename T >

friend class CommandTestBaseWithParam

friend

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

frc2/command/CommandScheduler.h

Public Types

Public Member Functions

Static Public Member Functions

Friends

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Action

◆ InterruptAction

Constructor & Destructor Documentation

◆ ~CommandScheduler()

◆ CommandScheduler()

Member Function Documentation

◆ Cancel() [1/4]

◆ Cancel() [2/4]

◆ Cancel() [3/4]

◆ Cancel() [4/4]

◆ CancelAll()

◆ Disable()

◆ Enable()

◆ GetActiveButtonLoop()

◆ GetDefaultButtonLoop()

◆ GetDefaultCommand()

◆ GetInstance()

◆ InitSendable()

◆ IsScheduled() [1/4]

◆ IsScheduled() [2/4]

◆ IsScheduled() [3/4]

◆ IsScheduled() [4/4]

◆ OnCommandExecute()

◆ OnCommandFinish()

◆ OnCommandInitialize()

◆ OnCommandInterrupt() [1/2]

◆ OnCommandInterrupt() [2/2]

◆ operator=()

◆ RegisterSubsystem() [1/3]

◆ RegisterSubsystem() [2/3]

◆ RegisterSubsystem() [3/3]

◆ RemoveDefaultCommand()

◆ RequireUngrouped() [1/3]

◆ RequireUngrouped() [2/3]

◆ RequireUngrouped() [3/3]

◆ RequireUngroupedAndUnscheduled() [1/3]

◆ RequireUngroupedAndUnscheduled() [2/3]

◆ RequireUngroupedAndUnscheduled() [3/3]

◆ Requiring()

◆ Run()

◆ Schedule() [1/4]

◆ Schedule() [2/4]

◆ Schedule() [3/4]

◆ Schedule() [4/4]

◆ SetActiveButtonLoop()

◆ SetDefaultCommand() [1/2]

◆ SetDefaultCommand() [2/2]

◆ SetPeriod()

◆ UnregisterAllSubsystems()

◆ UnregisterSubsystem() [1/3]

◆ UnregisterSubsystem() [2/3]

◆ UnregisterSubsystem() [3/3]

Friends And Related Function Documentation

◆ CommandTestBase

◆ CommandTestBaseWithParam