The StatefulActionNode is the preferred way to implement asynchronous Actions. It is actually easier to use correctly, when compared with ThreadedAction. More...

#include <action_node.h>

Inheritance diagram for BT::StatefulActionNode:

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Collaboration diagram for BT::StatefulActionNode:

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Public Member Functions
	StatefulActionNode (const std::string &name, const NodeConfig &config)

virtual NodeStatus	onStart ()=0

virtual NodeStatus	onRunning ()=0
	method invoked when the action is already in the RUNNING state.

virtual void	onHalted ()=0

bool	isHaltRequested () const

Public Member Functions inherited from BT::ActionNodeBase
	ActionNodeBase (const std::string &name, const NodeConfig &config)

	ActionNodeBase (const ActionNodeBase &)=delete

ActionNodeBase &	operator= (const ActionNodeBase &)=delete

	ActionNodeBase (ActionNodeBase &&)=delete

ActionNodeBase &	operator= (ActionNodeBase &&)=delete

virtual NodeType	type () const override final

Public Member Functions inherited from BT::LeafNode
	LeafNode (const std::string &name, const NodeConfig &config)

	LeafNode (const LeafNode &)=delete

LeafNode &	operator= (const LeafNode &)=delete

	LeafNode (LeafNode &&)=delete

LeafNode &	operator= (LeafNode &&)=delete

Public Member Functions inherited from BT::TreeNode
	TreeNode (std::string name, NodeConfig config)
	TreeNode main constructor.

	TreeNode (const TreeNode &other)=delete

TreeNode &	operator= (const TreeNode &other)=delete

	TreeNode (TreeNode &&other) noexcept

TreeNode &	operator= (TreeNode &&other) noexcept

virtual BT::NodeStatus	executeTick ()
	The method that should be used to invoke tick() and setStatus();.

void	haltNode ()

bool	isHalted () const

NodeStatus	status () const

const std::string &	name () const
	Name of the instance, not the type.

BT::NodeStatus	waitValidStatus ()

virtual NodeType	type () const =0

StatusChangeSubscriber	subscribeToStatusChange (StatusChangeCallback callback)
	subscribeToStatusChange is used to attach a callback to a status change. When StatusChangeSubscriber goes out of scope (it is a shared_ptr) the callback is unsubscribed automatically.

void	setPreTickFunction (PreTickCallback callback)

void	setPostTickFunction (PostTickCallback callback)

void	setTickMonitorCallback (TickMonitorCallback callback)

uint16_t	UID () const

const std::string &	fullPath () const

const std::string &	registrationName () const
	registrationName is the ID used by BehaviorTreeFactory to create an instance.

const NodeConfig &	config () const

template<typename T >
Result	getInput (const std::string &key, T &destination) const

template<typename T >
Expected< Timestamp >	getInputStamped (const std::string &key, T &destination) const
	getInputStamped is similar to getInput(dey, destination), but it returns also the Timestamp object, that can be used to check if a value was updated and when.

template<typename T >
Expected< T >	getInput (const std::string &key) const

template<typename T >
Expected< StampedValue< T > >	getInputStamped (const std::string &key) const

template<typename T >
Result	setOutput (const std::string &key, const T &value)
	setOutput modifies the content of an Output port

AnyPtrLocked	getLockedPortContent (const std::string &key)
	getLockedPortContent should be used when:

StringView	getRawPortValue (const std::string &key) const

void	emitWakeUpSignal ()
	Notify that the tree should be ticked again()

bool	requiresWakeUp () const

Protected Member Functions
NodeStatus	tick () override final
	Method to be implemented by the user.

void	halt () override final

Protected Member Functions inherited from BT::TreeNode
NodeConfig &	config ()

virtual BT::NodeStatus	tick ()=0
	Method to be implemented by the user.

void	resetStatus ()
	Set the status to IDLE.

void	setRegistrationID (StringView ID)

void	setWakeUpInstance (std::shared_ptr< WakeUpSignal > instance)

void	modifyPortsRemapping (const PortsRemapping &new_remapping)

void	setStatus (NodeStatus new_status)
	setStatus changes the status of the node. it will throw if you try to change the status to IDLE, because your parent node should do that, not the user!

PreScripts &	preConditionsScripts ()

PostScripts &	postConditionsScripts ()

template<typename T >
T	parseString (const std::string &str) const

Additional Inherited Members
Public Types inherited from BT::TreeNode
typedef std::shared_ptr< TreeNode >	Ptr

using	StatusChangeSignal = Signal< TimePoint, const TreeNode &, NodeStatus, NodeStatus >

using	StatusChangeSubscriber = StatusChangeSignal::Subscriber

using	StatusChangeCallback = StatusChangeSignal::CallableFunction

using	PreTickCallback = std::function< NodeStatus(TreeNode &)>

using	PostTickCallback = std::function< NodeStatus(TreeNode &, NodeStatus)>

using	TickMonitorCallback = std::function< void(TreeNode &, NodeStatus, std::chrono::microseconds)>

Static Public Member Functions inherited from BT::TreeNode
static bool	isBlackboardPointer (StringView str, StringView *stripped_pointer=nullptr)
	Check a string and return true if it matches the pattern: {...}.

static StringView	stripBlackboardPointer (StringView str)

static Expected< StringView >	getRemappedKey (StringView port_name, StringView remapped_port)

template<class DerivedT , typename... ExtraArgs>
static std::unique_ptr< TreeNode >	Instantiate (const std::string &name, const NodeConfig &config, ExtraArgs... args)

Protected Types inherited from BT::TreeNode
using	PreScripts = std::array< ScriptFunction, size_t(PreCond::COUNT_)>

using	PostScripts = std::array< ScriptFunction, size_t(PostCond::COUNT_)>

Detailed Description

The StatefulActionNode is the preferred way to implement asynchronous Actions. It is actually easier to use correctly, when compared with ThreadedAction.

It is particularly useful when your code contains a request-reply pattern, i.e. when the actions sends an asynchronous request, then checks periodically if the reply has been received and, eventually, analyze the reply to determine if the result is SUCCESS or FAILURE.

-) an action that was in IDLE state will call onStart()

-) A RUNNING action will call onRunning()

-) if halted, method onHalted() is invoked

Member Function Documentation

◆ halt()

void BT::StatefulActionNode::halt ( )

finaloverrideprotectedvirtual

The method used to interrupt the execution of a RUNNING node. Only Async nodes that may return RUNNING should implement it.

Implements BT::TreeNode.

◆ onHalted()

virtual void BT::StatefulActionNode::onHalted ( )

pure virtual

when the method halt() is called and the action is RUNNING, this method is invoked. This is a convenient place todo a cleanup, if needed.

Implemented in BT::SleepNode, and BT::TestNode.

◆ onRunning()

virtual NodeStatus BT::StatefulActionNode::onRunning ( )

pure virtual

method invoked when the action is already in the RUNNING state.

Implemented in BT::SleepNode, and BT::TestNode.

◆ onStart()

virtual NodeStatus BT::StatefulActionNode::onStart ( )

pure virtual

Method called once, when transitioning from the state IDLE. If it returns RUNNING, this becomes an asynchronous node.

Implemented in BT::SleepNode, and BT::TestNode.

◆ tick()

NodeStatus BT::StatefulActionNode::tick ( )

finaloverrideprotectedvirtual

Method to be implemented by the user.

Implements BT::TreeNode.

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

include/behaviortree_cpp/action_node.h

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ halt()

◆ onHalted()

◆ onRunning()

◆ onStart()

◆ tick()