QGraphicsItemAnimation¶
Synopsis¶
Functions¶
- def clear ()
- def horizontalScaleAt (step)
- def horizontalShearAt (step)
- def item ()
- def matrixAt (step)
- def posAt (step)
- def posList ()
- def rotationAt (step)
- def rotationList ()
- def scaleList ()
- def setItem (item)
- def setPosAt (step, pos)
- def setRotationAt (step, angle)
- def setScaleAt (step, sx, sy)
- def setShearAt (step, sh, sv)
- def setTimeLine (timeLine)
- def setTranslationAt (step, dx, dy)
- def shearList ()
- def timeLine ()
- def translationList ()
- def verticalScaleAt (step)
- def verticalShearAt (step)
- def xTranslationAt (step)
- def yTranslationAt (step)
Virtual functions¶
- def afterAnimationStep (step)
- def beforeAnimationStep (step)
Detailed Description¶
The PySide.QtGui.QGraphicsItemAnimation class provides simple animation support for PySide.QtGui.QGraphicsItem .
The PySide.QtGui.QGraphicsItemAnimation class animates a PySide.QtGui.QGraphicsItem . You can schedule changes to the item’s transformation matrix at specified steps. The PySide.QtGui.QGraphicsItemAnimation class has a current step value. When this value changes the transformations scheduled at that step are performed. The current step of the animation is set with the setStep() function.
PySide.QtGui.QGraphicsItemAnimation will do a simple linear interpolation between the nearest adjacent scheduled changes to calculate the matrix. For instance, if you set the position of an item at values 0.0 and 1.0, the animation will show the item moving in a straight line between these positions. The same is true for scaling and rotation.
It is usual to use the class with a PySide.QtCore.QTimeLine . The timeline’s PySide.QtCore.QTimeLine.valueChanged() signal is then connected to the setStep() slot. For example, you can set up an item for rotation by calling setRotationAt() for different step values. The animations timeline is set with the PySide.QtGui.QGraphicsItemAnimation.setTimeLine() function.
An example animation with a timeline follows:
ball = QGraphicsEllipseItem(0, 0, 20, 20) timer = QTimeLine(5000) timer.setFrameRange(0, 100) animation = QGraphicsItemAnimation() animation.setItem(ball) animation.setTimeLine(timer) for i in range(200): animation.setPosAt(i / 200.0, QPointF(i, i)) scene = QGraphicsScene() scene.setSceneRect(0, 0, 250, 250) scene.addItem(ball) view = QGraphicsView(scene) view.show() timer.start()Note that steps lie between 0.0 and 1.0. It may be necessary to use PySide.QtCore.QTimeLine.setUpdateInterval() . The default update interval is 40 ms. A scheduled transformation cannot be removed when set, so scheduling several transformations of the same kind (e.g., rotations) at the same step is not recommended.
See also
PySide.QtCore.QTimeLine Graphics View Framework
- class PySide.QtGui.QGraphicsItemAnimation([parent=None])¶
Parameters: parent – PySide.QtCore.QObject Constructs an animation object with the given parent .
- PySide.QtGui.QGraphicsItemAnimation.afterAnimationStep(step)¶
Parameters: step – PySide.QtCore.qreal This method is meant to be overridden in subclasses that need to execute additional code after a new step has taken place. The animation step is provided for use in cases where the action depends on its value.
- PySide.QtGui.QGraphicsItemAnimation.beforeAnimationStep(step)¶
Parameters: step – PySide.QtCore.qreal This method is meant to be overridden by subclassed that needs to execute additional code before a new step takes place. The animation step is provided for use in cases where the action depends on its value.
- PySide.QtGui.QGraphicsItemAnimation.clear()¶
Clears the scheduled transformations used for the animation, but retains the item and timeline.
- PySide.QtGui.QGraphicsItemAnimation.horizontalScaleAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the horizontal scale for the item at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.horizontalShearAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the horizontal shear for the item at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.item()¶
Return type: PySide.QtGui.QGraphicsItem Returns the item on which the animation object operates.
- PySide.QtGui.QGraphicsItemAnimation.matrixAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtGui.QMatrix Returns the matrix used to transform the item at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.posAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.QPointF Returns the position of the item at the given step value.
- PySide.QtGui.QGraphicsItemAnimation.posList()¶
Return type: Returns all explicitly inserted positions.
- PySide.QtGui.QGraphicsItemAnimation.reset()¶
Resets the item to its starting position and transformation.
You can call setStep(0) instead.
- PySide.QtGui.QGraphicsItemAnimation.rotationAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the angle at which the item is rotated at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.rotationList()¶
Return type: Returns all explicitly inserted rotations.
- PySide.QtGui.QGraphicsItemAnimation.scaleList()¶
Return type: Returns all explicitly inserted scales.
- PySide.QtGui.QGraphicsItemAnimation.setItem(item)¶
Parameters: item – PySide.QtGui.QGraphicsItem Sets the specified item to be used in the animation.
- PySide.QtGui.QGraphicsItemAnimation.setPosAt(step, pos)¶
Parameters: - step – PySide.QtCore.qreal
- pos – PySide.QtCore.QPointF
Sets the position of the item at the given step value to the point specified.
- PySide.QtGui.QGraphicsItemAnimation.setRotationAt(step, angle)¶
Parameters: - step – PySide.QtCore.qreal
- angle – PySide.QtCore.qreal
Sets the rotation of the item at the given step value to the angle specified.
- PySide.QtGui.QGraphicsItemAnimation.setScaleAt(step, sx, sy)¶
Parameters: - step – PySide.QtCore.qreal
- sx – PySide.QtCore.qreal
- sy – PySide.QtCore.qreal
Sets the scale of the item at the given step value using the horizontal and vertical scale factors specified by sx and sy .
- PySide.QtGui.QGraphicsItemAnimation.setShearAt(step, sh, sv)¶
Parameters: - step – PySide.QtCore.qreal
- sh – PySide.QtCore.qreal
- sv – PySide.QtCore.qreal
Sets the shear of the item at the given step value using the horizontal and vertical shear factors specified by sh and sv .
- PySide.QtGui.QGraphicsItemAnimation.setStep(x)¶
Parameters: x – PySide.QtCore.qreal Sets the current step value for the animation, causing the transformations scheduled at this step to be performed.
- PySide.QtGui.QGraphicsItemAnimation.setTimeLine(timeLine)¶
Parameters: timeLine – PySide.QtCore.QTimeLine Sets the timeline object used to control the rate of animation to the timeLine specified.
- PySide.QtGui.QGraphicsItemAnimation.setTranslationAt(step, dx, dy)¶
Parameters: - step – PySide.QtCore.qreal
- dx – PySide.QtCore.qreal
- dy – PySide.QtCore.qreal
Sets the translation of the item at the given step value using the horizontal and vertical coordinates specified by dx and dy .
- PySide.QtGui.QGraphicsItemAnimation.shearList()¶
Return type: Returns all explicitly inserted shears.
- PySide.QtGui.QGraphicsItemAnimation.timeLine()¶
Return type: PySide.QtCore.QTimeLine Returns the timeline object used to control the rate at which the animation occurs.
- PySide.QtGui.QGraphicsItemAnimation.translationList()¶
Return type: Returns all explicitly inserted translations.
- PySide.QtGui.QGraphicsItemAnimation.verticalScaleAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the vertical scale for the item at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.verticalShearAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the vertical shear for the item at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.xTranslationAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the horizontal translation of the item at the specified step value.
- PySide.QtGui.QGraphicsItemAnimation.yTranslationAt(step)¶
Parameters: step – PySide.QtCore.qreal Return type: PySide.QtCore.qreal Returns the vertical translation of the item at the specified step value.
