StateContext Class Reference

#include <StateContext.h>

Public Member Functions
	StateContext ()=default
	~StateContext ()=default
template<typename T >
void	set (const QString &key, T &&value)
template<typename T >
std::optional< T >	get (const QString &key) const
template<typename T >
T	getOr (const QString &key, const T &defaultValue) const
bool	contains (const QString &key) const
template<typename T >
bool	containsType (const QString &key) const
bool	remove (const QString &key)
void	clear ()
	Clear all stored values.
int	count () const
	Get the number of stored values.
QStringList	keys () const
	Get all keys in the context.
void	setVariant (const QString &key, const QVariant &value)
	Store a QVariant value.
QVariant	variant (const QString &key) const
	Retrieve a QVariant value.
bool	containsVariant (const QString &key) const
	Check if a variant key exists.

Detailed Description

Type-safe context for passing data between states in a state machine.

StateContext provides a way for states to share data without tight coupling. Data is stored by key and can be retrieved with type checking.

Example usage:

// In producer state
context->set("userId", 42);
context->set("userName", QString("Alice"));
 
// In consumer state
auto userId = context->get<int>("userId");
if (userId) {
    qDebug() << "User ID:" << *userId;
}

The context can also be accessed via QGCStateMachine::context().

Definition at line 30 of file StateContext.h.

Constructor & Destructor Documentation

StateContext()

StateContext::StateContext ( )

default

~StateContext()

StateContext::~StateContext ( )

default

Member Function Documentation

clear()

void StateContext::clear ( )

inline

Clear all stored values.

Definition at line 108 of file StateContext.h.

contains()

bool StateContext::contains ( const QString &  key ) const

inline

Check if a key exists in the context

Parameters

key	The key to check

Returns

true if the key exists

Definition at line 81 of file StateContext.h.

containsType()

template<typename T >

bool StateContext::containsType ( const QString &  key ) const

inline

Check if a key exists and holds the specified type

Parameters

key	The key to check

Returns

true if key exists and holds type T

Definition at line 90 of file StateContext.h.

containsVariant()

bool StateContext::containsVariant ( const QString &  key ) const

inline

Check if a variant key exists.

Definition at line 142 of file StateContext.h.

count()

int StateContext::count ( ) const

inline

Get the number of stored values.

Definition at line 114 of file StateContext.h.

get()

template<typename T >

std::optional< T > StateContext::get ( const QString &  key ) const

inline

Retrieve a value by key with type checking

Parameters

key	The key to look up

Returns

The value if found and type matches, std::nullopt otherwise

Definition at line 53 of file StateContext.h.

getOr()

template<typename T >

T StateContext::getOr ( const QString &  key, const T &  defaultValue  ) const

inline

Retrieve a value by key, returning a default if not found

Parameters

key	The key to look up
defaultValue	Value to return if key not found or type mismatch

Returns

The stored value or defaultValue

Definition at line 72 of file StateContext.h.

keys()

QStringList StateContext::keys ( ) const

inline

Get all keys in the context.

Definition at line 120 of file StateContext.h.

remove()

bool StateContext::remove ( const QString &  key )

inline

Remove a value by key

Parameters

key	The key to remove

Returns

true if the key was found and removed

Definition at line 102 of file StateContext.h.

set()

template<typename T >

void StateContext::set ( const QString &  key, T &&  value  )

inline

Store a value with the given key

Parameters

key	Unique identifier for the value
value	The value to store

Definition at line 44 of file StateContext.h.

setVariant()

void StateContext::setVariant ( const QString &  key, const QVariant &  value  )

inline

Store a QVariant value.

Definition at line 130 of file StateContext.h.

variant()

QVariant StateContext::variant ( const QString &  key ) const

inline

Retrieve a QVariant value.

Definition at line 136 of file StateContext.h.

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

• src/Utilities/StateMachine/Helpers/StateContext.h