#include <qqmlsynchronizer_p.h>

Inheritance diagram for QQmlSynchronizer:

Collaboration diagram for QQmlSynchronizer:

Signals
void	sourceObjectChanged ()
void	sourcePropertyChanged ()
void	targetObjectChanged ()
void	targetPropertyChanged ()
void	valueBounced (QObject *object, const QString &property)
void	valueIgnored (QObject *object, const QString &property)
Signals inherited from QObject
void	destroyed (QObject *=nullptr)
	This signal is emitted immediately before the object obj is destroyed, after any instances of QPointer have been notified, and cannot be blocked.
void	objectNameChanged (const QString &objectName, QPrivateSignal)
	This signal is emitted after the object's name has been changed.

Public Member Functions
	QQmlSynchronizer (QObject *parent=nullptr)
	\qmlmodule Qt.labs.synchronizer \title Qt Labs Synchronizer QML Types
QObject *	sourceObject () const
	\qmlproperty QtObject Qt.labs.synchronizer::Synchronizer::sourceObject
void	setSourceObject (QObject *object)
QString	sourceProperty () const
	\qmlproperty string Qt.labs.synchronizer::Synchronizer::sourceProperty
void	setSourceProperty (const QString &property)
QObject *	targetObject () const
	\qmlproperty QtObject Qt.labs.synchronizer::Synchronizer::targetObject
void	setTargetObject (QObject *object)
QString	targetProperty () const
	\qmlproperty string Qt.labs.synchronizer::Synchronizer::targetProperty
void	setTargetProperty (const QString &property)
Public Member Functions inherited from QObject
Q_INVOKABLE	QObject (QObject *parent=nullptr)
	Constructs an object with parent object parent.
virtual	~QObject ()
	Destroys the object, deleting all its child objects.
virtual bool	event (QEvent *event)
	This virtual function receives events to an object and should return true if the event e was recognized and processed.
virtual bool	eventFilter (QObject watched, QEvent event)
	Filters events if this object has been installed as an event filter for the watched object.
QString	objectName () const
Q_WEAK_OVERLOAD void	setObjectName (const QString &name)
	Sets the object's name to name.
void	setObjectName (QAnyStringView name)
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
QBindable< QString >	bindableObjectName ()
bool	isWidgetType () const
	Returns `true` if the object is a widget; otherwise returns `false`.
bool	isWindowType () const
	Returns `true` if the object is a window; otherwise returns `false`.
bool	isQuickItemType () const
	Returns `true` if the object is a QQuickItem; otherwise returns `false`.
bool	isQmlObjectType () const
	Returns whether the object has been created by the QML engine or ownership has been explicitly set via QJSEngine::setObjectOwnership().
bool	signalsBlocked () const noexcept
	Returns `true` if signals are blocked; otherwise returns `false`.
bool	blockSignals (bool b) noexcept
	If block is true, signals emitted by this object are blocked (i.e., emitting a signal will not invoke anything connected to it).
QThread *	thread () const
	Returns the thread in which the object lives.
bool	moveToThread (QThread *thread QT6_DECL_NEW_OVERLOAD_TAIL)
	Changes the thread affinity for this object and its children and returns `true` on success.
int	startTimer (int interval, Qt::TimerType timerType=Qt::CoarseTimer)
	This is an overloaded function that will start a timer of type timerType and a timeout of interval milliseconds.
int	startTimer (std::chrono::nanoseconds time, Qt::TimerType timerType=Qt::CoarseTimer)
void	killTimer (int id)
	Kills the timer with timer identifier, id.
void	killTimer (Qt::TimerId id)
template<typename T>
T	findChild (QAnyStringView aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns the child of this object that can be cast into type T and that is called name, or \nullptr if there is no such object.
template<typename T>
QList< T >	findChildren (QAnyStringView aName, Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	Returns all children of this object with the given name that can be cast to type T, or an empty list if there are no such objects.
template<typename T>
T	findChild (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
template<typename T>
QList< T >	findChildren (Qt::FindChildOptions options=Qt::FindChildrenRecursively) const
	This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.
const QObjectList &	children () const
	Returns a list of child objects.
void	setParent (QObject *parent)
	Makes the object a child of parent.
void	installEventFilter (QObject *filterObj)
	Installs an event filter filterObj on this object.
void	removeEventFilter (QObject *obj)
	Removes an event filter object obj from this object.
QMetaObject::Connection	connect (const QObject sender, const char signal, const char *member, Qt::ConnectionType type=Qt::AutoConnection) const
bool	disconnect (const char signal=nullptr, const QObject receiver=nullptr, const char *member=nullptr) const
bool	disconnect (const QObject receiver, const char member=nullptr) const
void	dumpObjectTree () const
	Dumps a tree of children to the debug output.
void	dumpObjectInfo () const
	Dumps information about signal connections, etc.
bool	setProperty (const char *name, const QVariant &value)
	Sets the value of the object's name property to value.
bool	setProperty (const char *name, QVariant &&value)
QVariant	property (const char *name) const
	Returns the value of the object's name property.
QList< QByteArray >	dynamicPropertyNames () const
QBindingStorage *	bindingStorage ()
const QBindingStorage *	bindingStorage () const
QObject *	parent () const
	Returns a pointer to the parent object.
bool	inherits (const char *classname) const
	Returns `true` if this object is an instance of a class that inherits className or a QObject subclass that inherits className; otherwise returns `false`.
Public Member Functions inherited from QQmlPropertyValueSource
	QQmlPropertyValueSource ()
	Constructs a QQmlPropertyValueSource.
virtual	~QQmlPropertyValueSource ()
	Destroys the value source.
Public Member Functions inherited from QQmlFinalizerHook
virtual	~QQmlFinalizerHook ()

Protected Member Functions
void	setTarget (const QQmlProperty &target) final
	Set the target property for the value source.
void	componentFinalized () final
	The customization point provided by this interface.
Protected Member Functions inherited from QObject
QObject *	sender () const
	Returns a pointer to the object that sent the signal, if called in a slot activated by a signal; otherwise it returns \nullptr.
int	senderSignalIndex () const
int	receivers (const char *signal) const
	Returns the number of receivers connected to the signal.
bool	isSignalConnected (const QMetaMethod &signal) const
virtual void	timerEvent (QTimerEvent *event)
	This event handler can be reimplemented in a subclass to receive timer events for the object.
virtual void	childEvent (QChildEvent *event)
	This event handler can be reimplemented in a subclass to receive child events.
virtual void	customEvent (QEvent *event)
	This event handler can be reimplemented in a subclass to receive custom events.
virtual void	connectNotify (const QMetaMethod &signal)
virtual void	disconnectNotify (const QMetaMethod &signal)
	QObject (QObjectPrivate &dd, QObject *parent=nullptr)

Properties
QObject *	sourceObject
QString	sourceProperty
QObject *	targetObject
QString	targetProperty
Properties inherited from QObject
QString	objectName
	the name of this object

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe
Static Public Member Functions inherited from QObject
static QMetaObject::Connection	connect (const QObject sender, const char signal, const QObject receiver, const char member, Qt::ConnectionType=Qt::AutoConnection)
	\threadsafe
static QMetaObject::Connection	connect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &method, Qt::ConnectionType type=Qt::AutoConnection)
template<typename Func1, typename Func2>
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::ContextTypeForFunctor< Func2 >::ContextType context, Func2 &&slot, Qt::ConnectionType type=Qt::AutoConnection)
template<typename Func1, typename Func2>
static QMetaObject::Connection	connect (const typename QtPrivate::FunctionPointer< Func1 >::Object *sender, Func1 signal, Func2 &&slot)
static bool	disconnect (const QObject sender, const char signal, const QObject receiver, const char member)
	\threadsafe
static bool	disconnect (const QObject sender, const QMetaMethod &signal, const QObject receiver, const QMetaMethod &member)
static bool	disconnect (const QMetaObject::Connection &)
	Disconnect a connection.
template<typename Func1, typename Func2>
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const typename QtPrivate::FunctionPointer< Func2 >::Object receiver, Func2 slot)
template<typename Func1>
static bool	disconnect (const typename QtPrivate::FunctionPointer< Func1 >::Object sender, Func1 signal, const QObject receiver, void **zero)
Protected Attributes inherited from QObject
QScopedPointer< QObjectData >	d_ptr
Related Symbols inherited from QObject
template< class T > T	qobject_cast (const QObject *object)
	Returns the given object cast to type T if the object is of type T (or of a subclass); otherwise returns \nullptr.
template< typename T > T	qFindChildqFindChildren (const QObject *obj, const QString &name)()
template< typename T > QList< T >	qFindChildrenqFindChildren (const QObject *obj, const QString &name)()
	QObjectList
	\macro Q_CLASSINFO(Name, Value)

Detailed Description

Definition at line 29 of file qqmlsynchronizer_p.h.

Constructor & Destructor Documentation

◆ QQmlSynchronizer()

QQmlSynchronizer::QQmlSynchronizer ( QObject * parent = nullptr )

\qmlmodule Qt.labs.synchronizer \title Qt Labs Synchronizer QML Types

Synchronizer synchronizes values between two or more properties.

To use this module, import the module with the following line:

\qml import Qt.labs.synchronizer \endqml

\qmltype Synchronizer
\inqmlmodule Qt.labs.synchronizer
\since 6.10
\brief Synchronizes values between two or more properties.

A Synchronizer object binds two or more properties together so that a change
to any one of them automatically updates all others. While doing so, none of
the bindings on any of the properties are broken. You can use Synchronizer if
the direction of data flow between two properties is not pre-determined. For
example, a TextInput may be initialized with a model value but should also
update the model value when editing is finished.

\note The input elements provided by Qt Quick and Qt Quick Controls solve this
      problem by providing user interaction signals separate from value change
      signals and hiding the value assignments in C++ code. You \e{don't} need
      Synchronizer for their internals. However, it may still be useful when
      connecting a control to a model.

Consider the following example.

\section1 Without Synchronizer

\qml

MyCustomTextInput.qml Item { property string text function append(characters: string) { text += characters } [...] } \endqml

You may be inclined to populate the text property from a model and update the model when the textChanged signal is received.

\qml Does not work! Item { id: root property string model: "lorem ipsum" MyCustomTextInput { text: root.model onTextChanged: root.model = text } } \endqml

This does not work. When the append function is called, the text property is modified, and the binding that updates it from the model property is broken. The next time the model is updated independently text is not updated anymore.

To solve this, you can omit the binding altogether and use only signals for updating both properties. This way you would need to give up the convenience of bindings.

Or, you can use Synchronizer.

Definition at line 418 of file qqmlsynchronizer.cpp.

Member Function Documentation

◆ componentFinalized()

void QQmlSynchronizer::componentFinalized ( )

finalprotectedvirtual

The customization point provided by this interface.

See the class description for why it is useful and how it compares to componentComplete.

See also: QQmlParserStatus::componentComplete

Implements QQmlFinalizerHook.

Definition at line 438 of file qqmlsynchronizer.cpp.

◆ setSourceObject()

void QQmlSynchronizer::setSourceObject ( QObject * object )

Definition at line 459 of file qqmlsynchronizer.cpp.

◆ setSourceProperty()

void QQmlSynchronizer::setSourceProperty ( const QString & property )

Definition at line 488 of file qqmlsynchronizer.cpp.

◆ setTarget()

void QQmlSynchronizer::setTarget ( const QQmlProperty & property )

finalprotectedvirtual

Set the target property for the value source.

This method will be called by the QML engine when assigning a value source.

Implements QQmlPropertyValueSource.

Definition at line 423 of file qqmlsynchronizer.cpp.

◆ setTargetObject()

void QQmlSynchronizer::setTargetObject ( QObject * object )

Definition at line 517 of file qqmlsynchronizer.cpp.

◆ setTargetProperty()

void QQmlSynchronizer::setTargetProperty ( const QString & property )

Definition at line 546 of file qqmlsynchronizer.cpp.

◆ sourceObject()

QObject * QQmlSynchronizer::sourceObject ( ) const

\qmlproperty QtObject Qt.labs.synchronizer::Synchronizer::sourceObject

This property holds the \l{sourceObject} part of the \l{sourceObject}/\l{sourceProperty} pair that together can specify one of the properties Synchronizer will synchronize.

Definition at line 453 of file qqmlsynchronizer.cpp.

◆ sourceObjectChanged

void QQmlSynchronizer::sourceObjectChanged ( )

signal

◆ sourceProperty()

QString QQmlSynchronizer::sourceProperty ( ) const

\qmlproperty string Qt.labs.synchronizer::Synchronizer::sourceProperty

This sourceProperty holds the \l{sourceProperty} part of the \l{sourceObject}/\l{sourceProperty} pair that together can specify one of the properties Synchronizer will synchronize.

Definition at line 482 of file qqmlsynchronizer.cpp.

◆ sourcePropertyChanged

void QQmlSynchronizer::sourcePropertyChanged ( )

signal

◆ targetObject()

QObject * QQmlSynchronizer::targetObject ( ) const

\qmlproperty QtObject Qt.labs.synchronizer::Synchronizer::targetObject

This property holds the \l{targetObject} part of the \l{targetObject}/\l{targetProperty} pair that together can specify one of the properties Synchronizer will synchronize.

Definition at line 511 of file qqmlsynchronizer.cpp.

◆ targetObjectChanged

void QQmlSynchronizer::targetObjectChanged ( )

signal

◆ targetProperty()

QString QQmlSynchronizer::targetProperty ( ) const

\qmlproperty string Qt.labs.synchronizer::Synchronizer::targetProperty

This targetProperty holds the \l{targetProperty} part of the \l{targetObject}/\l{targetProperty} pair that together can specify one of the properties Synchronizer will synchronize.

Definition at line 540 of file qqmlsynchronizer.cpp.

◆ targetPropertyChanged

void QQmlSynchronizer::targetPropertyChanged ( )

signal

◆ valueBounced

void QQmlSynchronizer::valueBounced	(	QObject *	object,
		const QString &	property )

signal

◆ valueIgnored

void QQmlSynchronizer::valueIgnored	(	QObject *	object,
		const QString &	property )

signal

Property Documentation

◆ sourceObject

QObject * QQmlSynchronizer::sourceObject

readwrite

Definition at line 35 of file qqmlsynchronizer_p.h.

◆ sourceProperty

QString QQmlSynchronizer::sourceProperty

readwrite

Definition at line 37 of file qqmlsynchronizer_p.h.

◆ targetObject

QObject * QQmlSynchronizer::targetObject

readwrite

Definition at line 39 of file qqmlsynchronizer_p.h.

◆ targetProperty

QString QQmlSynchronizer::targetProperty

readwrite

Definition at line 41 of file qqmlsynchronizer_p.h.

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

qtdeclarative/src/labs/synchronizer/qqmlsynchronizer_p.h (ab008ba17bb60de807e47a469da47fe63de8d0fd)
qtdeclarative/src/labs/synchronizer/qqmlsynchronizer.cpp (9d768789ffd69a92354fdef0c29b25f9e54b4e22)

Signals

Public Member Functions

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QQmlSynchronizer()

Member Function Documentation

◆ componentFinalized()

◆ setSourceObject()

◆ setSourceProperty()

◆ setTarget()

◆ setTargetObject()

◆ setTargetProperty()

◆ sourceObject()

◆ sourceObjectChanged

◆ sourceProperty()

◆ sourcePropertyChanged

◆ targetObject()

◆ targetObjectChanged

◆ targetProperty()

◆ targetPropertyChanged

◆ valueBounced

◆ valueIgnored

Property Documentation

◆ sourceObject

◆ sourceProperty

◆ targetObject

◆ targetProperty