QAbstractAnimation

The QAbstractAnimation class is the base of all animations. More

Inheritance diagram of PySide2.QtCore.QAbstractAnimation

Inherited by: QAnimationGroup, QParallelAnimationGroup, QPauseAnimation, QPropertyAnimation, QSequentialAnimationGroup, QVariantAnimation

New in version 4.6.

Synopsis

Functions

Virtual functions

Slots

Signals

Detailed Description

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: Running , Stopped , or Paused –as defined by the State enum. The current state can be changed by calling start() , stop() , pause() , or 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 will emit stateChanged() whenever its state changes.

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() signal is emitted.

QAbstractAnimation provides pure virtual functions used by subclasses to track the progress of the animation: duration() and updateCurrentTime() . The 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.

By reimplementing updateState() , you can track the animation’s state changes, which is particularly useful for animations that are not driven by time.

class PySide2.QtCore.QAbstractAnimation([parent=None])
param parent

PySide2.QtCore.QObject

Constructs the QAbstractAnimation base class, and passes parent to QObject ‘s constructor.

PySide2.QtCore.QAbstractAnimation.Direction

This enum describes the direction of the animation when in Running state.

Constant

Description

QAbstractAnimation.Forward

The current time of the animation increases with time (i.e., moves from 0 and towards the end / duration).

QAbstractAnimation.Backward

The current time of the animation decreases with time (i.e., moves from the end / duration and towards 0).

See also

direction

PySide2.QtCore.QAbstractAnimation.State

This enum describes the state of the animation.

Constant

Description

QAbstractAnimation.Stopped

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

The animation is paused (i.e., temporarily suspended). Calling resume() will resume animation activity.

QAbstractAnimation.Running

The animation is running. While control is in the event loop, QAbstractAnimation will update its current time at regular intervals, calling updateCurrentTime() when appropriate.

See also

state() stateChanged()

PySide2.QtCore.QAbstractAnimation.DeletionPolicy

Constant

Description

QAbstractAnimation.KeepWhenStopped

The animation will not be deleted when stopped.

QAbstractAnimation.DeleteWhenStopped

The animation will be automatically deleted when stopped.

PySide2.QtCore.QAbstractAnimation.currentLoop()
Return type

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 emits the currentLoopChanged() signal.

PySide2.QtCore.QAbstractAnimation.currentLoopChanged(currentLoop)
Parameters

currentLoop – int

PySide2.QtCore.QAbstractAnimation.currentLoopTime()
Return type

int

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

See also

duration() currentTime

PySide2.QtCore.QAbstractAnimation.currentTime()
Return type

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 , 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() .

See also

loopCount currentLoopTime()

PySide2.QtCore.QAbstractAnimation.direction()
Return type

Direction

This property holds the direction of the animation when it is in Running state..

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() has been called.

By default, this property is set to Forward .

PySide2.QtCore.QAbstractAnimation.directionChanged(arg__1)
Parameters

arg__1Direction

PySide2.QtCore.QAbstractAnimation.duration()
Return type

int

This property holds the duration of the animation..

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

PySide2.QtCore.QAbstractAnimation.finished()
PySide2.QtCore.QAbstractAnimation.group()
Return type

PySide2.QtCore.QAnimationGroup

If this animation is part of a QAnimationGroup , this function returns a pointer to the group; otherwise, it returns None .

See also

addAnimation()

PySide2.QtCore.QAbstractAnimation.loopCount()
Return type

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.

PySide2.QtCore.QAbstractAnimation.pause()

Pauses the animation. When the animation is paused, state() returns Paused. The value of currentTime will remain unchanged until resume() or start() is called. If you want to continue from the current time, call resume() .

See also

start() state() resume()

PySide2.QtCore.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.

See also

start() pause() state()

PySide2.QtCore.QAbstractAnimation.setCurrentTime(msecs)
Parameters

msecs – 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 , 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() .

See also

loopCount currentLoopTime()

PySide2.QtCore.QAbstractAnimation.setDirection(direction)
Parameters

directionDirection

This property holds the direction of the animation when it is in Running state..

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() has been called.

By default, this property is set to Forward .

PySide2.QtCore.QAbstractAnimation.setLoopCount(loopCount)
Parameters

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.

PySide2.QtCore.QAbstractAnimation.setPaused(arg__1)
Parameters

arg__1 – bool

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

See also

state() pause() resume()

PySide2.QtCore.QAbstractAnimation.start([policy=KeepWhenStopped])
Parameters

policyDeletionPolicy

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 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.

See also

stop() state()

PySide2.QtCore.QAbstractAnimation.state()
Return type

State

This property holds state of the animation..

This property describes the current state of the animation. When the animation state changes, QAbstractAnimation emits the stateChanged() signal.

PySide2.QtCore.QAbstractAnimation.stateChanged(newState, oldState)
Parameters
PySide2.QtCore.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() and currentLoop() > loopCount() - 1), the finished() signal is emitted.

See also

start() state()

PySide2.QtCore.QAbstractAnimation.totalDuration()
Return type

int

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

See also

duration() currentTime

PySide2.QtCore.QAbstractAnimation.updateCurrentTime(currentTime)
Parameters

currentTime – int

This pure virtual function is called every time the animation’s currentTime changes.

See also

updateState()

PySide2.QtCore.QAbstractAnimation.updateDirection(direction)
Parameters

directionDirection

This virtual function is called by QAbstractAnimation when the direction of the animation is changed. The direction argument is the new direction.

See also

setDirection() direction()

PySide2.QtCore.QAbstractAnimation.updateState(newState, oldState)
Parameters

This virtual function is called by QAbstractAnimation when the state of the animation is changed from oldState to newState .

See also

start() stop() pause() resume()