内容

• 公共类型
• 特性
• 公共函数
• 公共槽
• 信号
• 保护函数
• 重实现保护函数
• 详细描述

QAbstractAnimation 类

The QAbstractAnimation 类是所有动画的基。 更多...

头：	#include <QAbstractAnimation>
qmake:	QT += core
Since:	Qt 4.6
继承：	QObject
继承者：	QAnimationGroup , QPauseAnimation , Qt3DAnimation::QKeyframeAnimation , Qt3DAnimation::QMorphingAnimation , Qt3DAnimation::QVertexBlendAnimation ，和 QVariantAnimation

• 所有成员列表，包括继承成员

公共类型

enum	DeletionPolicy { KeepWhenStopped, DeleteWhenStopped }
enum	Direction { Forward, Backward }
enum	State { Stopped, Paused, Running }

特性

currentLoop : const int currentTime : int direction : Direction

duration : const int loopCount : int state : const State

• 1 特性继承自 QObject

公共函数

	QAbstractAnimation (QObject * parent = Q_NULLPTR)
virtual	~QAbstractAnimation ()
int	currentLoop () const
int	currentLoopTime () const
int	currentTime () const
方向	direction () const
virtual int	duration () const = 0
QAnimationGroup *	group () const
int	loopCount () const
void	setDirection (Direction direction )
void	setLoopCount (int loopCount )
状态	state () const
int	totalDuration () const

• 32 公共函数继承自 QObject

公共槽

void	pause ()
void	resume ()
void	setCurrentTime (int msecs )
void	setPaused (bool paused )
void	start (QAbstractAnimation::DeletionPolicy policy = KeepWhenStopped)
void	stop ()

• 1 公共槽继承自 QObject

信号

void	currentLoopChanged (int currentLoop )
void	directionChanged (QAbstractAnimation::Direction newDirection )
void	finished ()
void	stateChanged (QAbstractAnimation::State newState , QAbstractAnimation::State oldState )

• 2 信号继承自 QObject

保护函数

virtual void	updateCurrentTime (int currentTime ) = 0
virtual void	updateDirection (QAbstractAnimation::Direction direction )
virtual void	updateState (QAbstractAnimation::State newState , QAbstractAnimation::State oldState )

重实现保护函数

virtual bool

event (QEvent * event )

• 9 保护函数继承自 QObject

额外继承成员

• 11 静态公共成员继承自 QObject

详细描述

The QAbstractAnimation 类是所有动画的基。

The class defines the functions for the functionality shared by all animations. By inheriting this class, you can create custom animations that plug into the rest of the animation framework.

The progress of an animation is given by its current time ( currentLoopTime ()), which is measured in milliseconds from the start of the animation (0) to its end ( duration ()). The value is updated automatically while the animation is running. It can also be set directly with setCurrentTime ().

At any point an animation is in one of three states: 运行 , Stopped ，或 Paused --as defined by the State enum. The current state can be changed by calling start (), stop (), pause ()，或 resume (). An animation will always reset its current time when it is started. If paused, it will continue with the same current time when resumed. When an animation is stopped, it cannot be resumed, but will keep its current time (until started again). QAbstractAnimation 将发射 stateChanged () 每当其状态改变时。

An animation can loop any number of times by setting the loopCount property. When an animation's current time reaches its duration (), it will reset the current time and keep running. A loop count of 1 (the default value) means that the animation will run one time. Note that a duration of -1 means that the animation will run until stopped; the current time will increase indefinitely. When the current time equals duration () and the animation is in its final loop, the Stopped state is entered, and the finished () 信号被发射。

QAbstractAnimation provides pure virtual functions used by subclasses to track the progress of the animation: duration () 和 updateCurrentTime ()。 duration () function lets you report a duration for the animation (as discussed above). The animation framework calls updateCurrentTime () when current time has changed. By reimplementing this function, you can track the animation progress. Note that neither the interval between calls nor the number of calls to this function are defined; though, it will normally be 60 updates per second.

通过重实现 updateState (), you can track the animation's state changes, which is particularly useful for animations that are not driven by time.

另请参阅 QVariantAnimation , QPropertyAnimation , QAnimationGroup ，和 动画框架 .

成员类型文档编制

enum QAbstractAnimation:: DeletionPolicy

常量	值	描述
QAbstractAnimation::KeepWhenStopped	0	The animation will not be deleted when stopped.
QAbstractAnimation::DeleteWhenStopped	1	The animation will be automatically deleted when stopped.

enum QAbstractAnimation:: Direction

This enum describes the direction of the animation when in 运行 状态。

常量	值	描述
QAbstractAnimation::Forward	0	The current time of the animation increases with time (i.e., moves from 0 and towards the end / duration).
QAbstractAnimation::Backward	1	The current time of the animation decreases with time (i.e., moves from the end / duration and towards 0).

另请参阅 direction .

enum QAbstractAnimation:: State

此枚举描述动画的状态。

常量	值	描述
QAbstractAnimation::Stopped	0	The animation is not running. This is the initial state of QAbstractAnimation , and the state QAbstractAnimation reenters when finished. The current time remain unchanged until either setCurrentTime () is called, or the animation is started by calling start ().
QAbstractAnimation::Paused	1	The animation is paused (i.e., temporarily suspended). Calling resume () will resume animation activity.
QAbstractAnimation::Running	2	The animation is running. While control is in the event loop, QAbstractAnimation will update its current time at regular intervals, calling updateCurrentTime () when appropriate.

另请参阅 state () 和 stateChanged ().

特性文档编制

currentLoop : const int

This property holds the current loop of the animation

This property describes the current loop of the animation. By default, the animation's loop count is 1, and so the current loop will always be 0. If the loop count is 2 and the animation runs past its duration, it will automatically rewind and restart at current time 0, and current loop 1, and so on.

When the current loop changes, QAbstractAnimation 发射 currentLoopChanged () 信号。

访问函数：

int	currentLoop () const

通知程序信号：

void	currentLoopChanged (int currentLoop )

currentTime : int

This property holds the current time and progress of the animation

This property describes the animation's current time. You can change the current time by calling setCurrentTime, or you can call start () and let the animation run, setting the current time automatically as the animation progresses.

The animation's current time starts at 0, and ends at totalDuration ().

访问函数：

int	currentTime () const
void	setCurrentTime (int msecs )

另请参阅 loopCount and currentLoopTime ().

direction : Direction

This property holds the direction of the animation when it is in 运行 状态。

This direction indicates whether the time moves from 0 towards the animation duration, or from the value of the duration and towards 0 after start () 被调用。

默认情况下，此特性被设为 Forward .

访问函数：

方向	direction () const
void	setDirection (Direction direction )

通知程序信号：

void	directionChanged (QAbstractAnimation::Direction newDirection )

duration : const int

此特性保持动画的持续时间。

If the duration is -1, it means that the duration is undefined. In this case, loopCount 被忽略。

访问函数：

virtual int

duration () const = 0

loopCount : int

This property holds the loop count of the animation

This property describes the loop count of the animation as an integer. By default this value is 1, indicating that the animation should run once only, and then stop. By changing it you can let the animation loop several times. With a value of 0, the animation will not run at all, and with a value of -1, the animation will loop forever until stopped. It is not supported to have loop on an animation that has an undefined duration. It will only run once.

访问函数：

int	loopCount () const
void	setLoopCount (int loopCount )

state : const State

动画的状态。

This property describes the current state of the animation. When the animation state changes, QAbstractAnimation 发射 stateChanged () 信号。

访问函数：

状态	state () const

通知程序信号：

void	stateChanged (QAbstractAnimation::State newState , QAbstractAnimation::State oldState )

成员函数文档编制

QAbstractAnimation:: QAbstractAnimation ( QObject * parent = Q_NULLPTR)

构造 QAbstractAnimation base class, and passes parent to QObject 的构造函数。

另请参阅 QVariantAnimation and QAnimationGroup .

[虚拟] QAbstractAnimation:: ~QAbstractAnimation ()

Stops the animation if it's running, then destroys the QAbstractAnimation . If the animation is part of a QAnimationGroup , it is automatically removed before it's destroyed.

[signal] void QAbstractAnimation:: currentLoopChanged ( int currentLoop )

QAbstractAnimation emits this signal whenever the current loop changes. currentLoop is the current loop.

注意： 通知程序信号对于特性 currentLoop .

另请参阅 currentLoop () 和 loopCount ().

int QAbstractAnimation:: currentLoopTime () const

Returns the current time inside the current loop. It can go from 0 to duration ().

另请参阅 duration () 和 currentTime .

[signal] void QAbstractAnimation:: directionChanged ( QAbstractAnimation::Direction newDirection )

QAbstractAnimation emits this signal whenever the direction has been changed. newDirection is the new direction.

注意： 通知程序信号对于特性 direction .

另请参阅 direction .

[pure virtual] int QAbstractAnimation:: duration () const

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.

注意： Getter 函数对于特性 duration .

另请参阅 loopCount .

[virtual protected] bool QAbstractAnimation:: event ( QEvent * event )

重实现自 QObject::event ().

[signal] void QAbstractAnimation:: finished ()

QAbstractAnimation emits this signal after the animation has stopped and has reached the end.

此信号被发射在 stateChanged ().

另请参阅 stateChanged ().

QAnimationGroup *QAbstractAnimation:: group () const

若此动画属于 QAnimationGroup , this function returns a pointer to the group; otherwise, it returns 0.

另请参阅 QAnimationGroup::addAnimation ().

[slot] void QAbstractAnimation:: pause ()

暂停动画。当动画被暂停时， state () returns Paused. The value of currentTime will remain unchanged until resume () 或 start () is called. If you want to continue from the current time, call resume ().

另请参阅 start (), state ()，和 resume ().

[slot] void QAbstractAnimation:: resume ()

Resumes the animation after it was paused. When the animation is resumed, it emits the resumed() and stateChanged () signals. The currenttime is not changed.

另请参阅 start (), pause ()，和 state ().

[slot] void QAbstractAnimation:: setPaused ( bool paused )

若 paused is true, the animation is paused. If paused is false, the animation is resumed.

另请参阅 state (), pause ()，和 resume ().

[slot] void QAbstractAnimation:: start ( QAbstractAnimation::DeletionPolicy policy = KeepWhenStopped)

Starts the animation. The policy argument says whether or not the animation should be deleted when it's done. When the animation starts, the stateChanged () signal is emitted, and state () returns Running. When control reaches the event loop, the animation will run by itself, periodically calling updateCurrentTime () as the animation progresses.

If the animation is currently stopped or has already reached the end, calling start() will rewind the animation and start again from the beginning. When the animation reaches the end, the animation will either stop, or if the loop level is more than 1, it will rewind and continue from the beginning.

If the animation is already running, this function does nothing.

另请参阅 stop () 和 state ().

[signal] void QAbstractAnimation:: stateChanged ( QAbstractAnimation::State newState , QAbstractAnimation::State oldState )

QAbstractAnimation emits this signal whenever the state of the animation has changed from oldState to newState . This signal is emitted after the virtual updateState () 函数被调用。

注意： 通知程序信号对于特性 state .

另请参阅 updateState ().

[slot] void QAbstractAnimation:: stop ()

Stops the animation. When the animation is stopped, it emits the stateChanged () signal, and state () returns Stopped. The current time is not changed.

If the animation stops by itself after reaching the end (i.e., currentLoopTime () == duration () 和 currentLoop () > loopCount () - 1), the finished () 信号被发射。

另请参阅 start () 和 state ().

int QAbstractAnimation:: totalDuration () const

Returns the total and effective duration of the animation, including the loop count.

另请参阅 duration () 和 currentTime .

[pure virtual protected] void QAbstractAnimation:: updateCurrentTime ( int currentTime )

This pure virtual function is called every time the animation's currentTime 改变。

另请参阅 updateState ().

[virtual protected] void QAbstractAnimation:: updateDirection ( QAbstractAnimation::Direction direction )

此虚函数被调用由 QAbstractAnimation when the direction of the animation is changed. The direction argument is the new direction.

另请参阅 setDirection () 和 direction ().

[virtual protected] void QAbstractAnimation:: updateState ( QAbstractAnimation::State newState , QAbstractAnimation::State oldState )

此虚函数被调用由 QAbstractAnimation when the state of the animation is changed from oldState to newState .

另请参阅 start (), stop (), pause ()，和 resume ().