Qt
Internal/Contributor docs for the Qt SDK. Note: These are NOT official API docs; those are found at https://doc.qt.io/
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\inmodule QtCore More...
#include <qvariantanimation.h>
Public Types | |
using | KeyValue = std::pair<qreal, QVariant> |
This is a typedef for std::pair<qreal, QVariant>. | |
typedef QList< KeyValue > | KeyValues |
This is a typedef for QList<KeyValue> | |
typedef QVariant(*) | Interpolator(const void *from, const void *to, qreal progress) |
Public Types inherited from QAbstractAnimation | |
enum | Direction { Forward , Backward } |
This enum describes the direction of the animation when in \l Running state. More... | |
enum | State { Stopped , Paused , Running } |
This enum describes the state of the animation. More... | |
enum | DeletionPolicy { KeepWhenStopped = 0 , DeleteWhenStopped } |
\value KeepWhenStopped The animation will not be deleted when stopped. More... | |
Signals | |
void | valueChanged (const QVariant &value) |
QVariantAnimation emits this signal whenever the current value changes. | |
Signals inherited from QAbstractAnimation | |
void | finished () |
QAbstractAnimation emits this signal after the animation has stopped and has reached the end. | |
void | stateChanged (QAbstractAnimation::State newState, QAbstractAnimation::State oldState) |
QAbstractAnimation emits this signal whenever the state of the animation has changed from oldState to newState. | |
void | currentLoopChanged (int currentLoop) |
QAbstractAnimation emits this signal whenever the current loop changes. | |
void | directionChanged (QAbstractAnimation::Direction) |
QAbstractAnimation emits this signal whenever the direction has been changed. | |
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 | |
QVariantAnimation (QObject *parent=nullptr) | |
Construct a QVariantAnimation object. | |
~QVariantAnimation () | |
Destroys the animation. | |
QVariant | startValue () const |
void | setStartValue (const QVariant &value) |
QVariant | endValue () const |
void | setEndValue (const QVariant &value) |
QVariant | keyValueAt (qreal step) const |
Returns the key frame value for the given step. | |
void | setKeyValueAt (qreal step, const QVariant &value) |
Creates a key frame at the given step with the given value. | |
KeyValues | keyValues () const |
Returns the key frames of this animation. | |
void | setKeyValues (const KeyValues &values) |
Replaces the current set of key frames with the given keyValues. | |
QVariant | currentValue () const |
int | duration () const override |
This pure virtual function returns the duration of the animation, and defines for how long QAbstractAnimation should update the current time. | |
void | setDuration (int msecs) |
QBindable< int > | bindableDuration () |
QEasingCurve | easingCurve () const |
void | setEasingCurve (const QEasingCurve &easing) |
QBindable< QEasingCurve > | bindableEasingCurve () |
Public Member Functions inherited from QAbstractAnimation | |
QAbstractAnimation (QObject *parent=nullptr) | |
Constructs the QAbstractAnimation base class, and passes parent to QObject's constructor. | |
virtual | ~QAbstractAnimation () |
Stops the animation if it's running, then destroys the QAbstractAnimation. | |
State | state () const |
QBindable< QAbstractAnimation::State > | bindableState () const |
QAnimationGroup * | group () const |
If this animation is part of a QAnimationGroup, this function returns a pointer to the group; otherwise, it returns \nullptr. | |
Direction | direction () const |
void | setDirection (Direction direction) |
QBindable< Direction > | bindableDirection () |
int | currentTime () const |
QBindable< int > | bindableCurrentTime () |
int | currentLoopTime () const |
Returns the current time inside the current loop. | |
int | loopCount () const |
void | setLoopCount (int loopCount) |
QBindable< int > | bindableLoopCount () |
int | currentLoop () const |
QBindable< int > | bindableCurrentLoop () const |
int | totalDuration () const |
Returns the total and effective duration of the animation, including the loop count. | |
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 | 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 . | |
Protected Member Functions | |
QVariantAnimation (QVariantAnimationPrivate &dd, QObject *parent=nullptr) | |
bool | event (QEvent *event) override |
\reimp | |
void | updateCurrentTime (int) override |
\reimp | |
void | updateState (QAbstractAnimation::State newState, QAbstractAnimation::State oldState) override |
\reimp | |
virtual void | updateCurrentValue (const QVariant &value) |
This virtual function is called every time the animation's current value changes. | |
virtual QVariant | interpolated (const QVariant &from, const QVariant &to, qreal progress) const |
This virtual function returns the linear interpolation between variants from and to, at progress, usually a value between 0 and 1. | |
Protected Member Functions inherited from QAbstractAnimation | |
QAbstractAnimation (QAbstractAnimationPrivate &dd, QObject *parent=nullptr) | |
virtual void | updateDirection (QAbstractAnimation::Direction direction) |
This virtual function is called by QAbstractAnimation when the direction of the animation is changed. | |
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 | |
QVariant | startValue |
the optional start value of the animation | |
QVariant | endValue |
the end value of the animation | |
QVariant | currentValue |
the current value of the animation. | |
int | duration |
the duration of the animation | |
QEasingCurve | easingCurve |
the easing curve of the animation | |
Properties inherited from QAbstractAnimation | |
State | state |
state of the animation. | |
int | loopCount |
the loop count of the animation | |
int | currentTime |
the current time and progress of the animation | |
int | currentLoop |
the current loop of the animation | |
Direction | direction |
the direction of the animation when it is in \l Running state. | |
int | duration |
the duration of the animation. | |
Properties inherited from QObject | |
QString | objectName |
the name of this object | |
Friends | |
template<typename T > | |
void | qRegisterAnimationInterpolator (QVariant(*func)(const T &, const T &, qreal)) |
\threadsafe | |
Additional Inherited Members | |
Public Slots inherited from QAbstractAnimation | |
void | start (QAbstractAnimation::DeletionPolicy policy=KeepWhenStopped) |
Starts the animation. | |
void | pause () |
Pauses the animation. | |
void | resume () |
Resumes the animation after it was paused. | |
void | setPaused (bool) |
If paused is true, the animation is paused. | |
void | stop () |
Stops the animation. | |
void | setCurrentTime (int msecs) |
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) | |
\inmodule QtCore
The QVariantAnimation class provides a base class for animations.
This class is part of \l{The Animation Framework}. It serves as a base class for property and item animations, with functions for shared functionality.
The class performs interpolation over \l{QVariant}s, but leaves using the interpolated values to its subclasses. Currently, Qt provides QPropertyAnimation, which animates Qt \l{Qt's Property System}{properties}. See the QPropertyAnimation class description if you wish to animate such properties.
You can then set start and end values for the property by calling setStartValue() and setEndValue(), and finally call start() to start the animation. QVariantAnimation will interpolate the property of the target object and emit valueChanged(). To react to a change in the current value you have to reimplement the updateCurrentValue() virtual function or connect to said signal.
It is also possible to set values at specified steps situated between the start and end value. The interpolation will then touch these points at the specified steps. Note that the start and end values are defined as the key values at 0.0 and 1.0.
There are two ways to affect how QVariantAnimation interpolates the values. You can set an easing curve by calling setEasingCurve(), and configure the duration by calling setDuration(). You can change how the \l{QVariant}s are interpolated by creating a subclass of QVariantAnimation, and reimplementing the virtual interpolated() function.
Subclassing QVariantAnimation can be an alternative if you have \l{QVariant}s that you do not wish to declare as Qt properties. Note, however, that you in most cases will be better off declaring your QVariant as a property.
Not all QVariant types are supported. Below is a list of currently supported QVariant types:
\list
If you need to interpolate other variant types, including custom types, you have to implement interpolation for these yourself. To do this, you can register an interpolator function for a given type. This function takes 3 parameters: the start value, the end value, and the current progress.
Example:
Another option is to reimplement interpolated(), which returns interpolation values for the value being interpolated.
\omit We need some snippets around here. \endomit
Definition at line 18 of file qvariantanimation.h.
This is a typedef for a pointer to a function with the following signature:
Definition at line 57 of file qvariantanimation.h.
using QVariantAnimation::KeyValue = std::pair<qreal, QVariant> |
This is a typedef for std::pair<qreal, QVariant>.
Definition at line 29 of file qvariantanimation.h.
This is a typedef for QList<KeyValue>
Definition at line 30 of file qvariantanimation.h.
Construct a QVariantAnimation object.
parent is passed to QAbstractAnimation's constructor.
Definition at line 311 of file qvariantanimation.cpp.
QVariantAnimation::~QVariantAnimation | ( | ) |
Destroys the animation.
Definition at line 325 of file qvariantanimation.cpp.
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protected |
Definition at line 318 of file qvariantanimation.cpp.
QBindable< int > QVariantAnimation::bindableDuration | ( | ) |
Definition at line 498 of file qvariantanimation.cpp.
QBindable< QEasingCurve > QVariantAnimation::bindableEasingCurve | ( | ) |
Definition at line 368 of file qvariantanimation.cpp.
QVariant QVariantAnimation::currentValue | ( | ) | const |
Definition at line 620 of file qvariantanimation.cpp.
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overridevirtual |
This pure virtual function returns the duration of the animation, and defines for how long QAbstractAnimation should update the current time.
This duration is local, and does not include the loop count.
A return value of -1 indicates that the animation has no defined duration; the animation should run forever until stopped. This is useful for animations that are not time driven, or where you cannot easily predict its duration (e.g., event driven audio playback in a game).
If the animation is a parallel QAnimationGroup, the duration will be the longest duration of all its animations. If the animation is a sequential QAnimationGroup, the duration will be the sum of the duration of all its animations.
Implements QAbstractAnimation.
Definition at line 477 of file qvariantanimation.cpp.
QEasingCurve QVariantAnimation::easingCurve | ( | ) | const |
Definition at line 351 of file qvariantanimation.cpp.
QVariant QVariantAnimation::endValue | ( | ) | const |
Definition at line 533 of file qvariantanimation.cpp.
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overrideprotectedvirtual |
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protectedvirtual |
This virtual function returns the linear interpolation between variants from and to, at progress, usually a value between 0 and 1.
You can reimplement this function in a subclass of QVariantAnimation to provide your own interpolation algorithm.
Note that in order for the interpolation to work with a QEasingCurve that return a value smaller than 0 or larger than 1 (such as QEasingCurve::InBack) you should make sure that it can extrapolate. If the semantic of the datatype does not allow extrapolation this function should handle that gracefully.
You should call the QVariantAnimation implementation of this function if you want your class to handle the types already supported by Qt (see class QVariantAnimation description for a list of supported types).
Definition at line 666 of file qvariantanimation.cpp.
Returns the key frame value for the given step.
The given step must be in the range 0 to 1. If there is no KeyValue for step, it returns an invalid QVariant.
Definition at line 551 of file qvariantanimation.cpp.
QVariantAnimation::KeyValues QVariantAnimation::keyValues | ( | ) | const |
Returns the key frames of this animation.
Definition at line 583 of file qvariantanimation.cpp.
void QVariantAnimation::setDuration | ( | int | msecs | ) |
Definition at line 483 of file qvariantanimation.cpp.
void QVariantAnimation::setEasingCurve | ( | const QEasingCurve & | easing | ) |
Definition at line 357 of file qvariantanimation.cpp.
Definition at line 538 of file qvariantanimation.cpp.
Creates a key frame at the given step with the given value.
The given step must be in the range 0 to 1.
Definition at line 573 of file qvariantanimation.cpp.
Replaces the current set of key frames with the given keyValues.
the step of the key frames must be in the range 0 to 1.
Definition at line 594 of file qvariantanimation.cpp.
Definition at line 520 of file qvariantanimation.cpp.
QVariant QVariantAnimation::startValue | ( | ) | const |
Definition at line 515 of file qvariantanimation.cpp.
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overrideprotectedvirtual |
This virtual function is called every time the animation's current value changes.
The value argument is the new current value.
The base class implementation does nothing.
Reimplemented in QPropertyAnimation.
Definition at line 110 of file qvariantanimation.cpp.
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overrideprotectedvirtual |
QVariantAnimation emits this signal whenever the current value changes.
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friend |
\threadsafe
Registers a custom interpolator func for the template type {T}. The interpolator has to be registered before the animation is constructed. To unregister (and use the default interpolator) set func to \nullptr.
Definition at line 81 of file qvariantanimation.h.
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read |
the current value of the animation.
This property describes the current value; an interpolated value between the \l{startValue}{start value} and the \l{endValue}{end value}, using the current time for progress. The value itself is obtained from interpolated(), which is called repeatedly as the animation is running.
QVariantAnimation calls the virtual updateCurrentValue() function when the current value changes. This is particularly useful for subclasses that need to track updates. For example, QPropertyAnimation uses this function to animate Qt \l{Qt's Property System}{properties}.
Definition at line 23 of file qvariantanimation.h.
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readwrite |
the duration of the animation
This property describes the duration in milliseconds of the animation. The default duration is 250 milliseconds.
Definition at line 24 of file qvariantanimation.h.
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readwrite |
the easing curve of the animation
This property defines the easing curve of the animation. By default, a linear easing curve is used, resulting in linear interpolation. Other curves are provided, for instance, QEasingCurve::InCirc, which provides a circular entry curve. Another example is QEasingCurve::InOutElastic, which provides an elastic effect on the values of the interpolated variant.
QVariantAnimation will use the QEasingCurve::valueForProgress() to transform the "normalized progress" (currentTime / totalDuration) of the animation into the effective progress actually used by the animation. It is this effective progress that will be the progress when interpolated() is called. Also, the steps in the keyValues are referring to this effective progress.
The easing curve is used with the interpolator, the interpolated() virtual function, and the animation's duration to control how the current value changes as the animation progresses.
Definition at line 25 of file qvariantanimation.h.
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readwrite |
the end value of the animation
This property describes the end value of the animation.
Definition at line 22 of file qvariantanimation.h.
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readwrite |
the optional start value of the animation
This property describes the optional start value of the animation. If omitted, or if a null QVariant is assigned as the start value, the animation will use the current position of the end when the animation is started.
Definition at line 21 of file qvariantanimation.h.