#include <qquickframeanimation_p.h>

Inheritance diagram for QQuickFrameAnimation:

Collaboration diagram for QQuickFrameAnimation:

Public Slots
void	start ()
	\qmlmethod QtQuick::FrameAnimation::start()

void	stop ()
	\qmlmethod QtQuick::FrameAnimation::stop()

void	restart ()
	\qmlmethod QtQuick::FrameAnimation::restart()

void	pause ()
	\qmlmethod QtQuick::FrameAnimation::pause()

void	resume ()
	\qmlmethod QtQuick::FrameAnimation::resume()

void	reset ()
	\qmlmethod QtQuick::FrameAnimation::reset()

Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe

Signals
void	triggered ()

void	runningChanged ()

void	pausedChanged ()

void	currentFrameChanged ()

void	frameTimeChanged ()

void	smoothFrameTimeChanged ()

void	elapsedTimeChanged ()

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
	QQuickFrameAnimation (QObject *parent=nullptr)
	\qmltype FrameAnimation \nativetype QQuickFrameAnimation \inqmlmodule QtQuick

bool	isRunning () const
	\qmlsignal QtQuick::FrameAnimation::triggered()

void	setRunning (bool running)

bool	isPaused () const
	\qmlproperty bool QtQuick::FrameAnimation::paused

void	setPaused (bool paused)

int	currentFrame () const
	\qmlproperty int QtQuick::FrameAnimation::currentFrame \readonly

qreal	frameTime () const
	\qmlproperty qreal QtQuick::FrameAnimation::frameTime \readonly

qreal	smoothFrameTime () const
	\qmlproperty qreal QtQuick::FrameAnimation::smoothFrameTime \readonly

qreal	elapsedTime () const
	\qmlproperty qreal QtQuick::FrameAnimation::elapsedTime \readonly

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	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 QQmlParserStatus
	QQmlParserStatus ()

virtual	~QQmlParserStatus ()

Protected Member Functions
void	classBegin () override

void	componentComplete () override

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
bool	running

bool	paused

int	currentFrame

qreal	frameTime

qreal	smoothFrameTime

qreal	elapsedTime

Properties inherited from QObject
QString	objectName
	the name of this object

Additional Inherited Members
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 26 of file qquickframeanimation_p.h.

Constructor & Destructor Documentation

◆ QQuickFrameAnimation()

QQuickFrameAnimation::QQuickFrameAnimation ( QObject * parent = nullptr )

\qmltype FrameAnimation \nativetype QQuickFrameAnimation \inqmlmodule QtQuick

Since: 6.4

Triggers a handler at every animation frame update.

A FrameAnimation can be used to trigger an action every time animations have progressed and an animation frame has been rendered. See the documentation about the \l{qtquick-visualcanvas-scenegraph.html}{Scene Graph} for in-depth information about the threaded and basic render loops.

For general animations, prefer using NumberAnimation and other Animation elements as those provide declarative way to describe the animations.

FrameAnimation on the other hand should be used for custom imperative animations and in use-cases like these: \list

When you need to run some code on every frame update. Or e.g. every other frame, maybe using progressive rendering.
When the speed / target is changing during the animation, normal QML animations can be too limiting.
When more accurate frame update time is needed, e.g. for fps counter. \endlist

Compared to Timer which allows to set the interval time, FrameAnimation runs always in synchronization with the animation updates. If you have used Timer with a short interval for custom animations like below, please consider switching to use FrameAnimation instead for smoother animations.

// BAD
Timer {
    interval: 16
    repeat: true
    running: true
    onTriggered: {
        // Animate something
    }
}
 
// GOOD
FrameAnimation {
    running: true
    onTriggered: {
        // Animate something
    }
}

Definition at line 146 of file qquickframeanimation.cpp.

Member Function Documentation

◆ classBegin()

void QQuickFrameAnimation::classBegin ( )

overrideprotectedvirtual

Implements QQmlParserStatus.

Definition at line 421 of file qquickframeanimation.cpp.

◆ componentComplete()

void QQuickFrameAnimation::componentComplete ( )

overrideprotectedvirtual

Implements QQmlParserStatus.

Definition at line 430 of file qquickframeanimation.cpp.

◆ currentFrame()

int QQuickFrameAnimation::currentFrame ( ) const

\qmlproperty int QtQuick::FrameAnimation::currentFrame \readonly

This property holds the number of frame updates since the start. When the frame animation is restarted, currentFrame starts from 0.

The following example shows how to react on frame updates.

FrameAnimation {
    running: true
    onTriggered: {
        // Run code on every frame update.
    }
}

This property can also be used for rendering only every nth frame. Consider an advanced usage where the UI contains two heavy elements and to reach smooth 60fps overall frame rate, you decide to render these heavy elements at 30fps, first one on every even frames and second one on every odd frames:

FrameAnimation {
    running: true
    onTriggered: {
        if (currentFrame % 2 == 0)
            updateUIElement1();
        else
            updateUIElement2();
   }
}

By default, frame is 0.

Definition at line 248 of file qquickframeanimation.cpp.

◆ currentFrameChanged

void QQuickFrameAnimation::currentFrameChanged ( )

signal

◆ elapsedTime()

qreal QQuickFrameAnimation::elapsedTime ( ) const

\qmlproperty qreal QtQuick::FrameAnimation::elapsedTime \readonly

This property holds the time (in seconds) since the previous start.

By default, elapsedTime is 0.

Definition at line 327 of file qquickframeanimation.cpp.

◆ elapsedTimeChanged

void QQuickFrameAnimation::elapsedTimeChanged ( )

signal

◆ frameTime()

qreal QQuickFrameAnimation::frameTime ( ) const

\qmlproperty qreal QtQuick::FrameAnimation::frameTime \readonly

This property holds the time (in seconds) since the previous frame update.

The following example shows how to use frameTime to animate item with varying speed, adjusting to screen refresh rates and possible fps drops.

Rectangle {
    id: rect
    property real speed: 90
    width: 100
    height: 100
    color: "red"
    anchors.centerIn: parent
}
 
FrameAnimation {
    id: frameAnimation
    running: true
    onTriggered: {
        // Rotate the item speed-degrees / second.
        rect.rotation += rect.speed * frameTime
    }
}

By default, frameTime is 0.

Definition at line 285 of file qquickframeanimation.cpp.

◆ frameTimeChanged

void QQuickFrameAnimation::frameTimeChanged ( )

signal

◆ isPaused()

bool QQuickFrameAnimation::isPaused ( ) const

\qmlproperty bool QtQuick::FrameAnimation::paused

If set to true, pauses the frame animation; otherwise resumes it.

paused defaults to false.

See also: pause(), resume()

Definition at line 195 of file qquickframeanimation.cpp.

◆ isRunning()

bool QQuickFrameAnimation::isRunning ( ) const

\qmlsignal QtQuick::FrameAnimation::triggered()

This signal is emitted when the FrameAnimation has progressed to a new frame.

\qmlproperty bool QtQuick::FrameAnimation::running

If set to true, starts the frame animation; otherwise stops it.

running defaults to false.

See also: stop(), start(), restart()

Definition at line 169 of file qquickframeanimation.cpp.

◆ pause

void QQuickFrameAnimation::pause ( )

slot

\qmlmethod QtQuick::FrameAnimation::pause()

Pauses the frame animation

If the frame animation is already paused or not running, calling this method has no effect. The paused property will be true following a call to pause().

Definition at line 379 of file qquickframeanimation.cpp.

◆ pausedChanged

void QQuickFrameAnimation::pausedChanged ( )

signal

◆ reset

void QQuickFrameAnimation::reset ( )

slot

\qmlmethod QtQuick::FrameAnimation::reset()

Resets the frame animation properties

Calling this method resets the frame and elapsedTime to their initial values (0). This method has no effect on running or paused properties and can be called while they are true or false.

The difference between calling reset() and restart() is that reset() will always initialize the properties while restart() initializes them only at the next frame update which doesn't happen e.g. if restart() is immediately followed by pause().

Definition at line 409 of file qquickframeanimation.cpp.

◆ restart

void QQuickFrameAnimation::restart ( )

slot

\qmlmethod QtQuick::FrameAnimation::restart()

Restarts the frame animation

If the FrameAnimation is not running it will be started, otherwise it will be stopped, reset to initial state and started. The running property will be true following a call to restart().

Definition at line 366 of file qquickframeanimation.cpp.

◆ resume

void QQuickFrameAnimation::resume ( )

slot

\qmlmethod QtQuick::FrameAnimation::resume()

Resumes a paused frame animation

If the frame animation is not paused or not running, calling this method has no effect. The paused property will be false following a call to resume().

Definition at line 391 of file qquickframeanimation.cpp.

◆ runningChanged

void QQuickFrameAnimation::runningChanged ( )

signal

◆ setPaused()

void QQuickFrameAnimation::setPaused ( bool paused )

Definition at line 201 of file qquickframeanimation.cpp.

◆ setRunning()

void QQuickFrameAnimation::setRunning ( bool running )

Definition at line 175 of file qquickframeanimation.cpp.

◆ smoothFrameTime()

qreal QQuickFrameAnimation::smoothFrameTime ( ) const

\qmlproperty qreal QtQuick::FrameAnimation::smoothFrameTime \readonly

This property holds the smoothed time (in seconds) since the previous frame update.

The following example shows how to use smoothFrameTime to show average fps.

Text {
    text: "fps: " + frameAnimation.fps.toFixed(0)
}
 
FrameAnimation {
    id: frameAnimation
    property real fps: smoothFrameTime > 0 ? (1.0 / smoothFrameTime) : 0
    running: true
}

By default, smoothFrameTime is 0.

Definition at line 313 of file qquickframeanimation.cpp.

◆ smoothFrameTimeChanged

void QQuickFrameAnimation::smoothFrameTimeChanged ( )

signal

◆ start

void QQuickFrameAnimation::start ( )

slot

\qmlmethod QtQuick::FrameAnimation::start()

Starts the frame animation

If the frame animation is already running, calling this method has no effect. The running property will be true following a call to start().

Definition at line 340 of file qquickframeanimation.cpp.

◆ stop

void QQuickFrameAnimation::stop ( )

slot

\qmlmethod QtQuick::FrameAnimation::stop()

Stops the frame animation

If the frame animation is not running, calling this method has no effect. Both the running and paused properties will be false following a call to stop().

Definition at line 352 of file qquickframeanimation.cpp.

◆ triggered

void QQuickFrameAnimation::triggered ( )

signal

Property Documentation

◆ currentFrame

int QQuickFrameAnimation::currentFrame

read

Definition at line 33 of file qquickframeanimation_p.h.

◆ elapsedTime

qreal QQuickFrameAnimation::elapsedTime

read

Definition at line 36 of file qquickframeanimation_p.h.

◆ frameTime

qreal QQuickFrameAnimation::frameTime

read

Definition at line 34 of file qquickframeanimation_p.h.

◆ paused

bool QQuickFrameAnimation::paused

readwrite

Definition at line 32 of file qquickframeanimation_p.h.

◆ running

bool QQuickFrameAnimation::running

readwrite

Definition at line 31 of file qquickframeanimation_p.h.

◆ smoothFrameTime

qreal QQuickFrameAnimation::smoothFrameTime

read

Definition at line 35 of file qquickframeanimation_p.h.

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

qtdeclarative/src/quick/util/qquickframeanimation_p.h (bd131dcbf579f822ac8cee98324dc1355f7cd314)
qtdeclarative/src/quick/util/qquickframeanimation.cpp (a464ff5bfa15201de64d05121dc192dbd4655890)

Public Slots

Signals

Public Member Functions

Protected Member Functions

Properties

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ QQuickFrameAnimation()

Member Function Documentation

◆ classBegin()

◆ componentComplete()

◆ currentFrame()

◆ currentFrameChanged

◆ elapsedTime()

◆ elapsedTimeChanged

◆ frameTime()

◆ frameTimeChanged

◆ isPaused()

◆ isRunning()

◆ pause

◆ pausedChanged

◆ reset

◆ restart

◆ resume

◆ runningChanged

◆ setPaused()

◆ setRunning()

◆ smoothFrameTime()

◆ smoothFrameTimeChanged

◆ start

◆ stop

◆ triggered

Property Documentation

◆ currentFrame

◆ elapsedTime

◆ frameTime

◆ paused

◆ running

◆ smoothFrameTime