The QPinchGesture class describes a pinch gesture made by the user.\inmodule QtWidgets. More...

#include <qgesture.h>

Inheritance diagram for QPinchGesture:

Collaboration diagram for QPinchGesture:

Public Types
enum	ChangeFlag { ScaleFactorChanged = 0x1 , RotationAngleChanged = 0x2 , CenterPointChanged = 0x4 }
	This enum describes the changes that can occur to the properties of the gesture object. More...

Public Types inherited from QGesture
enum	GestureCancelPolicy { CancelNone = 0 , CancelAllInContext }
	This enum describes how accepting a gesture can cancel other gestures automatically. More...

Public Member Functions
	QPinchGesture (QObject *parent=nullptr)

	~QPinchGesture ()
	Destructor.

ChangeFlags	totalChangeFlags () const

void	setTotalChangeFlags (ChangeFlags value)

ChangeFlags	changeFlags () const

void	setChangeFlags (ChangeFlags value)

QPointF	startCenterPoint () const

QPointF	lastCenterPoint () const

QPointF	centerPoint () const

void	setStartCenterPoint (const QPointF &value)

void	setLastCenterPoint (const QPointF &value)

void	setCenterPoint (const QPointF &value)

qreal	totalScaleFactor () const

qreal	lastScaleFactor () const

qreal	scaleFactor () const

void	setTotalScaleFactor (qreal value)

void	setLastScaleFactor (qreal value)

void	setScaleFactor (qreal value)

qreal	totalRotationAngle () const

qreal	lastRotationAngle () const

qreal	rotationAngle () const

void	setTotalRotationAngle (qreal value)

void	setLastRotationAngle (qreal value)

void	setRotationAngle (qreal value)

Public Member Functions inherited from QGesture
	QGesture (QObject *parent=nullptr)

	~QGesture ()
	Destroys the gesture object.

Qt::GestureType	gestureType () const

Qt::GestureState	state () const

QPointF	hotSpot () const

void	setHotSpot (const QPointF &value)

bool	hasHotSpot () const

void	unsetHotSpot ()

void	setGestureCancelPolicy (GestureCancelPolicy policy)

GestureCancelPolicy	gestureCancelPolicy () const

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.

void	moveToThread (QThread *thread)
	Changes the thread affinity for this object and its children.

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::milliseconds time, Qt::TimerType timerType=Qt::CoarseTimer)

void	killTimer (int id)
	Kills the timer with timer identifier, id.

template<typename T >
T	findChild (const QString &aName=QString(), 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 (const QString &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 >
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`.

Properties
ChangeFlags	totalChangeFlags
	the property of the gesture that has change

ChangeFlags	changeFlags
	the property of the gesture that has changed in the current step

qreal	totalScaleFactor
	the total scale factor

qreal	lastScaleFactor
	the last scale factor recorded for this gesture

qreal	scaleFactor
	the current scale factor

qreal	totalRotationAngle
	the total angle covered by the gesture

qreal	lastRotationAngle
	the last reported angle covered by the gesture motion

qreal	rotationAngle
	the angle covered by the gesture motion

QPointF	startCenterPoint
	the starting position of the center point

QPointF	lastCenterPoint
	the last position of the center point recorded for this gesture

QPointF	centerPoint
	the current center point

Properties inherited from QGesture
Qt::GestureState	state
	the current state of the gesture

Qt::GestureType	gestureType
	the type of the gesture

QGesture::GestureCancelPolicy	gestureCancelPolicy
	the policy for deciding what happens on accepting a gesture

QPointF	hotSpot
	The point that is used to find the receiver for the gesture event.

bool	hasHotSpot
	whether the gesture has a hot-spot

Properties inherited from QObject
QString	objectName
	the name of this object

Friends
class	QPinchGestureRecognizer

Additional Inherited Members
Public Slots inherited from QObject
void	deleteLater ()
	\threadsafe

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.

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 Member Functions inherited from QGesture
	QGesture (QGesturePrivate &dd, QObject *parent)

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)

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

The QPinchGesture class describes a pinch gesture made by the user.

\inmodule QtWidgets.

Since: 4.6

A pinch gesture is a form of touch user input in which the user typically touches two points on the input device with a thumb and finger, before moving them closer together or further apart to change the scale factor, zoom, or level of detail of the user interface.

For an overview of gesture handling in Qt and information on using gestures in your applications, see the \l{Gestures in Widgets and Graphics View} document.

Instead of repeatedly applying the same pinching gesture, the user may continue to touch the input device in one place, and apply a second touch to a new point, continuing the gesture. When this occurs, gesture events will continue to be delivered to the target object, containing an instance of QPinchGesture in the Qt::GestureUpdated state.

See also: QPanGesture, QSwipeGesture

Definition at line 102 of file qgesture.h.

Member Enumeration Documentation

◆ ChangeFlag

enum QPinchGesture::ChangeFlag

This enum describes the changes that can occur to the properties of the gesture object.

\value ScaleFactorChanged The scale factor held by scaleFactor changed. \value RotationAngleChanged The rotation angle held by rotationAngle changed. \value CenterPointChanged The center point held by centerPoint changed.

See also: changeFlags, totalChangeFlags

Enumerator
ScaleFactorChanged
RotationAngleChanged
CenterPointChanged

Definition at line 108 of file qgesture.h.

Constructor & Destructor Documentation

◆ QPinchGesture()

QPinchGesture::QPinchGesture ( QObject * parent = nullptr )

explicit

Definition at line 461 of file qgesture.cpp.

References QGesture::gestureType, and Qt::PinchGesture.

◆ ~QPinchGesture()

QPinchGesture::~QPinchGesture ( )

Destructor.

Definition at line 470 of file qgesture.cpp.

Member Function Documentation

◆ centerPoint()

QPointF QPinchGesture::centerPoint ( ) const

Definition at line 504 of file qgesture.cpp.

◆ changeFlags()

QPinchGesture::ChangeFlags QPinchGesture::changeFlags ( ) const

Definition at line 484 of file qgesture.cpp.

◆ lastCenterPoint()

QPointF QPinchGesture::lastCenterPoint ( ) const

Definition at line 499 of file qgesture.cpp.

◆ lastRotationAngle()

qreal QPinchGesture::lastRotationAngle ( ) const

Definition at line 561 of file qgesture.cpp.

◆ lastScaleFactor()

qreal QPinchGesture::lastScaleFactor ( ) const

Definition at line 530 of file qgesture.cpp.

◆ rotationAngle()

qreal QPinchGesture::rotationAngle ( ) const

Definition at line 566 of file qgesture.cpp.

◆ scaleFactor()

qreal QPinchGesture::scaleFactor ( ) const

Definition at line 535 of file qgesture.cpp.

◆ setCenterPoint()

void QPinchGesture::setCenterPoint ( const QPointF & value )

Definition at line 519 of file qgesture.cpp.

◆ setChangeFlags()

void QPinchGesture::setChangeFlags ( ChangeFlags value )

Definition at line 489 of file qgesture.cpp.

Referenced by QMacPinchGestureRecognizer::reset().

Here is the caller graph for this function:

◆ setLastCenterPoint()

void QPinchGesture::setLastCenterPoint ( const QPointF & value )

Definition at line 514 of file qgesture.cpp.

◆ setLastRotationAngle()

void QPinchGesture::setLastRotationAngle ( qreal value )

Definition at line 576 of file qgesture.cpp.

◆ setLastScaleFactor()

void QPinchGesture::setLastScaleFactor ( qreal value )

Definition at line 545 of file qgesture.cpp.

◆ setRotationAngle()

void QPinchGesture::setRotationAngle ( qreal value )

Definition at line 581 of file qgesture.cpp.

◆ setScaleFactor()

void QPinchGesture::setScaleFactor ( qreal value )

Definition at line 550 of file qgesture.cpp.

◆ setStartCenterPoint()

void QPinchGesture::setStartCenterPoint ( const QPointF & value )

Definition at line 509 of file qgesture.cpp.

◆ setTotalChangeFlags()

void QPinchGesture::setTotalChangeFlags ( ChangeFlags value )

Definition at line 479 of file qgesture.cpp.

◆ setTotalRotationAngle()

void QPinchGesture::setTotalRotationAngle ( qreal value )

Definition at line 571 of file qgesture.cpp.

◆ setTotalScaleFactor()

void QPinchGesture::setTotalScaleFactor ( qreal value )

Definition at line 540 of file qgesture.cpp.

◆ startCenterPoint()

QPointF QPinchGesture::startCenterPoint ( ) const

Definition at line 494 of file qgesture.cpp.

◆ totalChangeFlags()

QPinchGesture::ChangeFlags QPinchGesture::totalChangeFlags ( ) const

Definition at line 474 of file qgesture.cpp.

◆ totalRotationAngle()

qreal QPinchGesture::totalRotationAngle ( ) const

Definition at line 556 of file qgesture.cpp.

◆ totalScaleFactor()

qreal QPinchGesture::totalScaleFactor ( ) const

Definition at line 525 of file qgesture.cpp.

Friends And Related Symbol Documentation

◆ QPinchGestureRecognizer

friend class QPinchGestureRecognizer

friend

Definition at line 163 of file qgesture.h.

Property Documentation

◆ centerPoint

QPinchGesture::centerPoint

readwrite

the current center point

The center point is the midpoint between the two input points in the gesture.

See also: startCenterPoint, lastCenterPoint

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ changeFlags

QPinchGesture::changeFlags

readwrite

the property of the gesture that has changed in the current step

This property indicates which of the other properties has changed since the previous gesture event included information about this gesture. You can use this information to determine which aspect of your user interface needs to be updated.

See also: totalChangeFlags, scaleFactor, rotationAngle, centerPoint

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ lastCenterPoint

QPinchGesture::lastCenterPoint

readwrite

the last position of the center point recorded for this gesture

See also: centerPoint, startCenterPoint

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ lastRotationAngle

QPinchGesture::lastRotationAngle

readwrite

the last reported angle covered by the gesture motion

The last rotation angle is the angle as reported in the \l rotationAngle property when a previous gesture event was delivered for this gesture.

See also: rotationAngle, totalRotationAngle

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ lastScaleFactor

QPinchGesture::lastScaleFactor

readwrite

the last scale factor recorded for this gesture

The last scale factor contains the scale factor reported in the \l scaleFactor property when a previous gesture event included information about this gesture.

If no previous event was delivered with information about this gesture (i.e., this gesture object contains information about the first movement in the gesture) then this property contains zero.

See also: scaleFactor, totalScaleFactor

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ rotationAngle

QPinchGesture::rotationAngle

readwrite

the angle covered by the gesture motion

See also: totalRotationAngle, lastRotationAngle

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ scaleFactor

QPinchGesture::scaleFactor

readwrite

the current scale factor

The scale factor measures the scale factor associated with the distance between two of the user's inputs on a touch device.

See also: totalScaleFactor, lastScaleFactor

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ startCenterPoint

QPinchGesture::startCenterPoint

readwrite

the starting position of the center point

See also: centerPoint, lastCenterPoint

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ totalChangeFlags

QPinchGesture::totalChangeFlags

readwrite

the property of the gesture that has change

This property indicates which of the other properties has changed since the gesture has started. You can use this information to determine which aspect of your user interface needs to be updated.

See also: changeFlags, scaleFactor, rotationAngle, centerPoint

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ totalRotationAngle

QPinchGesture::totalRotationAngle

readwrite

the total angle covered by the gesture

This total angle measures the complete angle covered by the gesture. Usually, this is equal to the value held by the \l rotationAngle property, except in the case where the user performs multiple rotations by removing and repositioning one of the touch points, as described above. In this case, the total angle will be the sum of the rotation angles for the multiple stages of the gesture.

See also: rotationAngle, lastRotationAngle

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

◆ totalScaleFactor

QPinchGesture::totalScaleFactor

readwrite

the total scale factor

The total scale factor measures the total change in scale factor from the original value to the current scale factor.

See also: scaleFactor, lastScaleFactor

Definition at line 98 of file qgesture.h.

Referenced by operator<<().

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

qtbase/src/widgets/kernel/qgesture.h
qtbase/src/widgets/kernel/qgesture.cpp

Public Types

Public Member Functions

Properties

Friends

Additional Inherited Members

Detailed Description

Member Enumeration Documentation

◆ ChangeFlag

Constructor & Destructor Documentation

◆ QPinchGesture()

◆ ~QPinchGesture()

Member Function Documentation

◆ centerPoint()

◆ changeFlags()

◆ lastCenterPoint()

◆ lastRotationAngle()

◆ lastScaleFactor()

◆ rotationAngle()

◆ scaleFactor()

◆ setCenterPoint()

◆ setChangeFlags()

◆ setLastCenterPoint()

◆ setLastRotationAngle()

◆ setLastScaleFactor()

◆ setRotationAngle()

◆ setScaleFactor()

◆ setStartCenterPoint()

◆ setTotalChangeFlags()

◆ setTotalRotationAngle()

◆ setTotalScaleFactor()

◆ startCenterPoint()

◆ totalChangeFlags()

◆ totalRotationAngle()

◆ totalScaleFactor()

Friends And Related Symbol Documentation

◆ QPinchGestureRecognizer

Property Documentation

◆ centerPoint

◆ changeFlags

◆ lastCenterPoint

◆ lastRotationAngle

◆ lastScaleFactor

◆ rotationAngle

◆ scaleFactor

◆ startCenterPoint

◆ totalChangeFlags

◆ totalRotationAngle

◆ totalScaleFactor