def __activeControlMoved(self, pos):
# The active control point has moved, update the control
# rectangle
control = self.__activeControl
pos = control.pos()
rect = QRectF(self.__rect)
margins = self.__margins
# TODO: keyboard modifiers and constraints.
anchor = control.anchor()
if anchor & ControlPoint.Top:
rect.setTop(pos.y() + margins.top())
elif anchor & ControlPoint.Bottom:
rect.setBottom(pos.y() - margins.bottom())
if anchor & ControlPoint.Left:
rect.setLeft(pos.x() + margins.left())
elif anchor & ControlPoint.Right:
rect.setRight(pos.x() - margins.right())
changed = self.__rect != rect
self.blockSignals(True)
self.setRect(rect)
self.blockSignals(False)
if changed:
self.rectEdited.emit(rect.normalized())
def __activeControlMoved(self, pos):
# The active control point has moved, update the control
# rectangle
control = self.__activeControl
pos = control.pos()
rect = QRectF(self.__rect)
margins = self.__margins
# TODO: keyboard modifiers and constraints.
anchor = control.anchor()
if anchor & ControlPoint.Top:
rect.setTop(pos.y() + margins.top())
elif anchor & ControlPoint.Bottom:
rect.setBottom(pos.y() - margins.bottom())
if anchor & ControlPoint.Left:
rect.setLeft(pos.x() + margins.left())
elif anchor & ControlPoint.Right:
rect.setRight(pos.x() - margins.right())
changed = self.__rect != rect
self.blockSignals(True)
self.setRect(rect)
self.blockSignals(False)
if changed:
self.rectEdited.emit(rect.normalized())
class RectangleSelectionAction(UserInteraction):
"""
Select items in the scene using a Rectangle selection
"""
def __init__(self, document, *args, **kwargs):
UserInteraction.__init__(self, document, *args, **kwargs)
# The initial selection at drag start
self.initial_selection = None
# Selection when last updated in a mouseMoveEvent
self.last_selection = None
# A selection rect (`QRectF`)
self.selection_rect = None
# Keyboard modifiers
self.modifiers = 0
def mousePressEvent(self, event):
pos = event.scenePos()
any_item = self.scene.item_at(pos)
if not any_item and event.button() & Qt.LeftButton:
self.modifiers = event.modifiers()
self.selection_rect = QRectF(pos, QSizeF(0, 0))
self.rect_item = QGraphicsRectItem(
self.selection_rect.normalized())
self.rect_item.setPen(
QPen(QBrush(QColor(51, 153, 255, 192)), 0.4, Qt.SolidLine,
Qt.RoundCap))
self.rect_item.setBrush(QBrush(QColor(168, 202, 236, 192)))
self.rect_item.setZValue(-100)
# Clear the focus if necessary.
if not self.scene.stickyFocus():
self.scene.clearFocus()
if not self.modifiers & Qt.ControlModifier:
self.scene.clearSelection()
event.accept()
return True
else:
self.cancel(self.ErrorReason)
return False
def mouseMoveEvent(self, event):
if not self.rect_item.scene():
# Add the rect item to the scene when the mouse moves.
self.scene.addItem(self.rect_item)
self.update_selection(event)
return True
def mouseReleaseEvent(self, event):
if event.button() == Qt.LeftButton:
if self.initial_selection is None:
# A single click.
self.scene.clearSelection()
else:
self.update_selection(event)
self.end()
return True
def update_selection(self, event):
"""
Update the selection rectangle from a QGraphicsSceneMouseEvent
`event` instance.
"""
if self.initial_selection is None:
self.initial_selection = set(self.scene.selectedItems())
self.last_selection = self.initial_selection
pos = event.scenePos()
self.selection_rect = QRectF(self.selection_rect.topLeft(), pos)
# Make sure the rect_item does not cause the scene rect to grow.
rect = self._bound_selection_rect(self.selection_rect.normalized())
# Need that 0.5 constant otherwise the sceneRect will still
# grow (anti-aliasing correction by QGraphicsScene?)
pw = self.rect_item.pen().width() + 0.5
self.rect_item.setRect(rect.adjusted(pw, pw, -pw, -pw))
selected = self.scene.items(self.selection_rect.normalized(),
Qt.IntersectsItemShape, Qt.AscendingOrder)
selected = set([item for item in selected if \
item.flags() & Qt.ItemIsSelectable])
if self.modifiers & Qt.ControlModifier:
for item in selected | self.last_selection | \
self.initial_selection:
item.setSelected((item in selected)
^ (item in self.initial_selection))
else:
for item in selected.union(self.last_selection):
item.setSelected(item in selected)
self.last_selection = set(self.scene.selectedItems())
def end(self):
self.initial_selection = None
self.last_selection = None
self.modifiers = 0
self.rect_item.hide()
if self.rect_item.scene() is not None:
self.scene.removeItem(self.rect_item)
UserInteraction.end(self)
def viewport_rect(self):
"""
Return the bounding rect of the document's viewport on the scene.
"""
view = self.document.view()
vsize = view.viewport().size()
viewportrect = QRect(0, 0, vsize.width(), vsize.height())
return view.mapToScene(viewportrect).boundingRect()
def _bound_selection_rect(self, rect):
"""
Bound the selection `rect` to a sensible size.
"""
srect = self.scene.sceneRect()
vrect = self.viewport_rect()
maxrect = srect.united(vrect)
return rect.intersected(maxrect)
class RectangleSelectionAction(UserInteraction):
"""
Select items in the scene using a Rectangle selection
"""
def __init__(self, document, *args, **kwargs):
UserInteraction.__init__(self, document, *args, **kwargs)
# The initial selection at drag start
self.initial_selection = None
# Selection when last updated in a mouseMoveEvent
self.last_selection = None
# A selection rect (`QRectF`)
self.selection_rect = None
# Keyboard modifiers
self.modifiers = 0
def mousePressEvent(self, event):
pos = event.scenePos()
any_item = self.scene.item_at(pos)
if not any_item and event.button() & Qt.LeftButton:
self.modifiers = event.modifiers()
self.selection_rect = QRectF(pos, QSizeF(0, 0))
self.rect_item = QGraphicsRectItem(
self.selection_rect.normalized()
)
self.rect_item.setPen(
QPen(QBrush(QColor(51, 153, 255, 192)),
0.4, Qt.SolidLine, Qt.RoundCap)
)
self.rect_item.setBrush(
QBrush(QColor(168, 202, 236, 192))
)
self.rect_item.setZValue(-100)
# Clear the focus if necessary.
if not self.scene.stickyFocus():
self.scene.clearFocus()
if not self.modifiers & Qt.ControlModifier:
self.scene.clearSelection()
event.accept()
return True
else:
self.cancel(self.ErrorReason)
return False
def mouseMoveEvent(self, event):
if not self.rect_item.scene():
# Add the rect item to the scene when the mouse moves.
self.scene.addItem(self.rect_item)
self.update_selection(event)
return True
def mouseReleaseEvent(self, event):
if event.button() == Qt.LeftButton:
if self.initial_selection is None:
# A single click.
self.scene.clearSelection()
else:
self.update_selection(event)
self.end()
return True
def update_selection(self, event):
"""
Update the selection rectangle from a QGraphicsSceneMouseEvent
`event` instance.
"""
if self.initial_selection is None:
self.initial_selection = set(self.scene.selectedItems())
self.last_selection = self.initial_selection
pos = event.scenePos()
self.selection_rect = QRectF(self.selection_rect.topLeft(), pos)
# Make sure the rect_item does not cause the scene rect to grow.
rect = self._bound_selection_rect(self.selection_rect.normalized())
# Need that 0.5 constant otherwise the sceneRect will still
# grow (anti-aliasing correction by QGraphicsScene?)
pw = self.rect_item.pen().width() + 0.5
self.rect_item.setRect(rect.adjusted(pw, pw, -pw, -pw))
selected = self.scene.items(self.selection_rect.normalized(),
Qt.IntersectsItemShape,
Qt.AscendingOrder)
selected = set([item for item in selected if \
item.flags() & Qt.ItemIsSelectable])
if self.modifiers & Qt.ControlModifier:
for item in selected | self.last_selection | \
self.initial_selection:
item.setSelected(
(item in selected) ^ (item in self.initial_selection)
)
else:
for item in selected.union(self.last_selection):
item.setSelected(item in selected)
self.last_selection = set(self.scene.selectedItems())
def end(self):
self.initial_selection = None
self.last_selection = None
self.modifiers = 0
self.rect_item.hide()
if self.rect_item.scene() is not None:
self.scene.removeItem(self.rect_item)
UserInteraction.end(self)
def viewport_rect(self):
"""
Return the bounding rect of the document's viewport on the scene.
"""
view = self.document.view()
vsize = view.viewport().size()
viewportrect = QRect(0, 0, vsize.width(), vsize.height())
return view.mapToScene(viewportrect).boundingRect()
def _bound_selection_rect(self, rect):
"""
Bound the selection `rect` to a sensible size.
"""
srect = self.scene.sceneRect()
vrect = self.viewport_rect()
maxrect = srect.united(vrect)
return rect.intersected(maxrect)
class ControlPointRect(QGraphicsObject):
Free = 0
KeepAspectRatio = 1
KeepCenter = 2
rectChanged = Signal(QRectF)
rectEdited = Signal(QRectF)
def __init__(self, parent=None, rect=None, constraints=0, **kwargs):
QGraphicsObject.__init__(self, parent, **kwargs)
self.setFlag(QGraphicsItem.ItemHasNoContents)
self.setFlag(QGraphicsItem.ItemIsFocusable)
self.__rect = rect if rect is not None else QRectF()
self.__margins = QMargins()
points = [
ControlPoint(self, ControlPoint.Left),
ControlPoint(self, ControlPoint.Top),
ControlPoint(self, ControlPoint.TopLeft),
ControlPoint(self, ControlPoint.Right),
ControlPoint(self, ControlPoint.TopRight),
ControlPoint(self, ControlPoint.Bottom),
ControlPoint(self, ControlPoint.BottomLeft),
ControlPoint(self, ControlPoint.BottomRight),
]
assert points == sorted(points, key=lambda p: p.anchor())
self.__points = dict((p.anchor(), p) for p in points)
if self.scene():
self.__installFilter()
for p in points:
p.setFlag(QGraphicsItem.ItemIsFocusable)
p.setFocusProxy(self)
self.controlPoint(ControlPoint.Top).setConstraint(Qt.Vertical)
self.controlPoint(ControlPoint.Bottom).setConstraint(Qt.Vertical)
self.controlPoint(ControlPoint.Left).setConstraint(Qt.Horizontal)
self.controlPoint(ControlPoint.Right).setConstraint(Qt.Horizontal)
self.__constraints = constraints
self.__activeControl = None
self.__pointsLayout()
def controlPoint(self, anchor):
"""
Return the anchor point (:class:`ControlPoint`) at anchor position
or `None` if an anchor point is not set.
"""
return self.__points.get(anchor)
def setRect(self, rect):
"""
Set the control point rectangle (:class:`QRectF`)
"""
if self.__rect != rect:
self.__rect = QRectF(rect)
self.__pointsLayout()
self.prepareGeometryChange()
self.rectChanged.emit(rect.normalized())
def rect(self):
"""
Return the control point rectangle.
"""
# Return the rect normalized. During the control point move the
# rect can change to an invalid size, but the layout must still
# know to which point does an unnormalized rect side belong,
# so __rect is left unnormalized.
# NOTE: This means all signal emits (rectChanged/Edited) must
# also emit normalized rects
return self.__rect.normalized()
rect_ = Property(QRectF, fget=rect, fset=setRect, user=True)
def setControlMargins(self, *margins):
"""Set the controls points on the margins around `rect`
"""
if len(margins) > 1:
margins = QMargins(*margins)
else:
margins = margins[0]
if isinstance(margins, int):
margins = QMargins(margins, margins, margins, margins)
if self.__margins != margins:
self.__margins = margins
self.__pointsLayout()
def controlMargins(self):
return self.__margins
def setConstraints(self, constraints):
raise NotImplementedError
def isControlActive(self):
"""Return the state of the control. True if the control is
active (user is dragging one of the points) False otherwise.
"""
return self.__activeControl is not None
def itemChange(self, change, value):
if change == QGraphicsItem.ItemSceneHasChanged and self.scene():
self.__installFilter()
return QGraphicsObject.itemChange(self, change, value)
def sceneEventFilter(self, obj, event):
try:
obj = toGraphicsObjectIfPossible(obj)
if isinstance(obj, ControlPoint):
etype = event.type()
if (etype == QEvent.GraphicsSceneMousePress
and event.button() == Qt.LeftButton):
self.__setActiveControl(obj)
elif (etype == QEvent.GraphicsSceneMouseRelease
and event.button() == Qt.LeftButton):
self.__setActiveControl(None)
except Exception:
log.error("Error in 'ControlPointRect.sceneEventFilter'",
exc_info=True)
return QGraphicsObject.sceneEventFilter(self, obj, event)
def __installFilter(self):
# Install filters on the control points.
try:
for p in self.__points.values():
p.installSceneEventFilter(self)
except Exception:
log.error("Error in ControlPointRect.__installFilter",
exc_info=True)
def __pointsLayout(self):
"""Layout the control points
"""
rect = self.__rect
margins = self.__margins
rect = rect.adjusted(-margins.left(), -margins.top(), margins.right(),
margins.bottom())
center = rect.center()
cx, cy = center.x(), center.y()
left, top, right, bottom = rect.left(), rect.top(), rect.right(
), rect.bottom()
self.controlPoint(ControlPoint.Left).setPos(left, cy)
self.controlPoint(ControlPoint.Right).setPos(right, cy)
self.controlPoint(ControlPoint.Top).setPos(cx, top)
self.controlPoint(ControlPoint.Bottom).setPos(cx, bottom)
self.controlPoint(ControlPoint.TopLeft).setPos(left, top)
self.controlPoint(ControlPoint.TopRight).setPos(right, top)
self.controlPoint(ControlPoint.BottomLeft).setPos(left, bottom)
self.controlPoint(ControlPoint.BottomRight).setPos(right, bottom)
def __setActiveControl(self, control):
if self.__activeControl != control:
if self.__activeControl is not None:
self.__activeControl.positionChanged[QPointF].disconnect(
self.__activeControlMoved)
self.__activeControl = control
if control is not None:
control.positionChanged[QPointF].connect(
self.__activeControlMoved)
def __activeControlMoved(self, pos):
# The active control point has moved, update the control
# rectangle
control = self.__activeControl
pos = control.pos()
rect = QRectF(self.__rect)
margins = self.__margins
# TODO: keyboard modifiers and constraints.
anchor = control.anchor()
if anchor & ControlPoint.Top:
rect.setTop(pos.y() + margins.top())
elif anchor & ControlPoint.Bottom:
rect.setBottom(pos.y() - margins.bottom())
if anchor & ControlPoint.Left:
rect.setLeft(pos.x() + margins.left())
elif anchor & ControlPoint.Right:
rect.setRight(pos.x() - margins.right())
changed = self.__rect != rect
self.blockSignals(True)
self.setRect(rect)
self.blockSignals(False)
if changed:
self.rectEdited.emit(rect.normalized())
def boundingRect(self):
return QRectF()
class ControlPointRect(QGraphicsObject):
Free = 0
KeepAspectRatio = 1
KeepCenter = 2
rectChanged = Signal(QRectF)
rectEdited = Signal(QRectF)
def __init__(self, parent=None, rect=None, constraints=0, **kwargs):
QGraphicsObject.__init__(self, parent, **kwargs)
self.setFlag(QGraphicsItem.ItemHasNoContents)
self.setFlag(QGraphicsItem.ItemIsFocusable)
self.__rect = rect if rect is not None else QRectF()
self.__margins = QMargins()
points = \
[ControlPoint(self, ControlPoint.Left),
ControlPoint(self, ControlPoint.Top),
ControlPoint(self, ControlPoint.TopLeft),
ControlPoint(self, ControlPoint.Right),
ControlPoint(self, ControlPoint.TopRight),
ControlPoint(self, ControlPoint.Bottom),
ControlPoint(self, ControlPoint.BottomLeft),
ControlPoint(self, ControlPoint.BottomRight)
]
assert(points == sorted(points, key=lambda p: p.anchor()))
self.__points = dict((p.anchor(), p) for p in points)
if self.scene():
self.__installFilter()
for p in points:
p.setFlag(QGraphicsItem.ItemIsFocusable)
p.setFocusProxy(self)
self.controlPoint(ControlPoint.Top).setConstraint(Qt.Vertical)
self.controlPoint(ControlPoint.Bottom).setConstraint(Qt.Vertical)
self.controlPoint(ControlPoint.Left).setConstraint(Qt.Horizontal)
self.controlPoint(ControlPoint.Right).setConstraint(Qt.Horizontal)
self.__constraints = constraints
self.__activeControl = None
self.__pointsLayout()
def controlPoint(self, anchor):
"""
Return the anchor point (:class:`ControlPoint`) at anchor position
or `None` if an anchor point is not set.
"""
return self.__points.get(anchor)
def setRect(self, rect):
"""
Set the control point rectangle (:class:`QRectF`)
"""
if self.__rect != rect:
self.__rect = QRectF(rect)
self.__pointsLayout()
self.prepareGeometryChange()
self.rectChanged.emit(rect.normalized())
def rect(self):
"""
Return the control point rectangle.
"""
# Return the rect normalized. During the control point move the
# rect can change to an invalid size, but the layout must still
# know to which point does an unnormalized rect side belong,
# so __rect is left unnormalized.
# NOTE: This means all signal emits (rectChanged/Edited) must
# also emit normalized rects
return self.__rect.normalized()
rect_ = Property(QRectF, fget=rect, fset=setRect, user=True)
def setControlMargins(self, *margins):
"""Set the controls points on the margins around `rect`
"""
if len(margins) > 1:
margins = QMargins(*margins)
else:
margins = margins[0]
if isinstance(margins, int):
margins = QMargins(margins, margins, margins, margins)
if self.__margins != margins:
self.__margins = margins
self.__pointsLayout()
def controlMargins(self):
return self.__margins
def setConstraints(self, constraints):
raise NotImplementedError
def isControlActive(self):
"""Return the state of the control. True if the control is
active (user is dragging one of the points) False otherwise.
"""
return self.__activeControl is not None
def itemChange(self, change, value):
if change == QGraphicsItem.ItemSceneHasChanged and self.scene():
self.__installFilter()
return QGraphicsObject.itemChange(self, change, value)
def sceneEventFilter(self, obj, event):
try:
obj = toGraphicsObjectIfPossible(obj)
if isinstance(obj, ControlPoint):
etype = event.type()
if etype == QEvent.GraphicsSceneMousePress and \
event.button() == Qt.LeftButton:
self.__setActiveControl(obj)
elif etype == QEvent.GraphicsSceneMouseRelease and \
event.button() == Qt.LeftButton:
self.__setActiveControl(None)
except Exception:
log.error("Error in 'ControlPointRect.sceneEventFilter'",
exc_info=True)
return QGraphicsObject.sceneEventFilter(self, obj, event)
def __installFilter(self):
# Install filters on the control points.
try:
for p in self.__points.values():
p.installSceneEventFilter(self)
except Exception:
log.error("Error in ControlPointRect.__installFilter",
exc_info=True)
def __pointsLayout(self):
"""Layout the control points
"""
rect = self.__rect
margins = self.__margins
rect = rect.adjusted(-margins.left(), -margins.top(),
margins.right(), margins.bottom())
center = rect.center()
cx, cy = center.x(), center.y()
left, top, right, bottom = \
rect.left(), rect.top(), rect.right(), rect.bottom()
self.controlPoint(ControlPoint.Left).setPos(left, cy)
self.controlPoint(ControlPoint.Right).setPos(right, cy)
self.controlPoint(ControlPoint.Top).setPos(cx, top)
self.controlPoint(ControlPoint.Bottom).setPos(cx, bottom)
self.controlPoint(ControlPoint.TopLeft).setPos(left, top)
self.controlPoint(ControlPoint.TopRight).setPos(right, top)
self.controlPoint(ControlPoint.BottomLeft).setPos(left, bottom)
self.controlPoint(ControlPoint.BottomRight).setPos(right, bottom)
def __setActiveControl(self, control):
if self.__activeControl != control:
if self.__activeControl is not None:
self.__activeControl.positionChanged[QPointF].disconnect(
self.__activeControlMoved
)
self.__activeControl = control
if control is not None:
control.positionChanged[QPointF].connect(
self.__activeControlMoved
)
def __activeControlMoved(self, pos):
# The active control point has moved, update the control
# rectangle
control = self.__activeControl
pos = control.pos()
rect = QRectF(self.__rect)
margins = self.__margins
# TODO: keyboard modifiers and constraints.
anchor = control.anchor()
if anchor & ControlPoint.Top:
rect.setTop(pos.y() + margins.top())
elif anchor & ControlPoint.Bottom:
rect.setBottom(pos.y() - margins.bottom())
if anchor & ControlPoint.Left:
rect.setLeft(pos.x() + margins.left())
elif anchor & ControlPoint.Right:
rect.setRight(pos.x() - margins.right())
changed = self.__rect != rect
self.blockSignals(True)
self.setRect(rect)
self.blockSignals(False)
if changed:
self.rectEdited.emit(rect.normalized())
def boundingRect(self):
return QRectF()
class ControlPointRect(QGraphicsObject):
class Constraint(enum.IntEnum):
Free = 0
KeepAspectRatio = 1
KeepCenter = 2
Free = Constraint.Free
KeepAspectRatio = Constraint.KeepAspectRatio
KeepCenter = Constraint.KeepCenter
rectChanged = Signal(QRectF)
rectEdited = Signal(QRectF)
def __init__(self, parent=None, rect=QRectF(), constraints=Free, **kwargs):
# type: (Optional[QGraphicsItem], QRectF, Constraint, Any) -> None
super().__init__(parent, **kwargs)
self.setFlag(QGraphicsItem.ItemHasNoContents)
self.setFlag(QGraphicsItem.ItemIsFocusable)
self.__rect = QRectF(rect) if rect is not None else QRectF()
self.__margins = QMargins()
points = [
ControlPoint(self,
ControlPoint.Left,
constraint=Qt.Horizontal,
cursor=Qt.SizeHorCursor),
ControlPoint(self,
ControlPoint.Top,
constraint=Qt.Vertical,
cursor=Qt.SizeVerCursor),
ControlPoint(self, ControlPoint.TopLeft,
cursor=Qt.SizeFDiagCursor),
ControlPoint(self,
ControlPoint.Right,
constraint=Qt.Horizontal,
cursor=Qt.SizeHorCursor),
ControlPoint(self,
ControlPoint.TopRight,
cursor=Qt.SizeBDiagCursor),
ControlPoint(self,
ControlPoint.Bottom,
constraint=Qt.Vertical,
cursor=Qt.SizeVerCursor),
ControlPoint(self,
ControlPoint.BottomLeft,
cursor=Qt.SizeBDiagCursor),
ControlPoint(self,
ControlPoint.BottomRight,
cursor=Qt.SizeFDiagCursor)
]
assert (points == sorted(points, key=lambda p: p.anchor()))
self.__points = dict((p.anchor(), p) for p in points)
if self.scene():
self.__installFilter()
for p in points:
p.setFlag(QGraphicsItem.ItemIsFocusable)
p.setFocusProxy(self)
self.__constraints = constraints
self.__activeControl = None # type: Optional[ControlPoint]
self.__pointsLayout()
def controlPoint(self, anchor):
# type: (ControlPoint.Anchor) -> ControlPoint
"""
Return the anchor point (:class:`ControlPoint`) for anchor position.
"""
return self.__points[anchor]
def setRect(self, rect):
# type: (QRectF) -> None
"""
Set the control point rectangle (:class:`QRectF`)
"""
if self.__rect != rect:
self.__rect = QRectF(rect)
self.__pointsLayout()
self.prepareGeometryChange()
self.rectChanged.emit(rect.normalized())
def rect(self):
# type: () -> QRectF
"""
Return the control point rectangle.
"""
# Return the rect normalized. During the control point move the
# rect can change to an invalid size, but the layout must still
# know to which point does an unnormalized rect side belong,
# so __rect is left unnormalized.
# NOTE: This means all signal emits (rectChanged/Edited) must
# also emit normalized rects
return self.__rect.normalized()
rect_ = Property(QRectF, fget=rect, fset=setRect, user=True)
def setControlMargins(self, *margins):
# type: (int) -> None
"""Set the controls points on the margins around `rect`
"""
if len(margins) > 1:
margins = QMargins(*margins)
elif len(margins) == 1:
margin = margins[0]
margins = QMargins(margin, margin, margin, margin)
else:
raise TypeError
if self.__margins != margins:
self.__margins = margins
self.__pointsLayout()
def controlMargins(self):
# type: () -> QMargins
return QMargins(self.__margins)
def setConstraints(self, constraints):
raise NotImplementedError
def isControlActive(self):
# type: () -> bool
"""Return the state of the control. True if the control is
active (user is dragging one of the points) False otherwise.
"""
return self.__activeControl is not None
def itemChange(self, change, value):
# type: (QGraphicsItem.GraphicsItemChange, Any) -> Any
if change == QGraphicsItem.ItemSceneHasChanged and self.scene():
self.__installFilter()
return super().itemChange(change, value)
def sceneEventFilter(self, obj, event):
# type: (QGraphicsItem, QEvent) -> bool
obj = toGraphicsObjectIfPossible(obj)
if isinstance(obj, ControlPoint):
etype = event.type()
if etype in (QEvent.GraphicsSceneMousePress,
QEvent.GraphicsSceneMouseDoubleClick) and \
event.button() == Qt.LeftButton:
self.__setActiveControl(obj)
elif etype == QEvent.GraphicsSceneMouseRelease and \
event.button() == Qt.LeftButton:
self.__setActiveControl(None)
return super().sceneEventFilter(obj, event)
def __installFilter(self):
# type: () -> None
# Install filters on the control points.
for p in self.__points.values():
p.installSceneEventFilter(self)
def __pointsLayout(self):
# type: () -> None
"""Layout the control points
"""
rect = self.__rect
margins = self.__margins
rect = rect.adjusted(-margins.left(), -margins.top(), margins.right(),
margins.bottom())
center = rect.center()
cx, cy = center.x(), center.y()
left, top, right, bottom = \
rect.left(), rect.top(), rect.right(), rect.bottom()
self.controlPoint(ControlPoint.Left).setPos(left, cy)
self.controlPoint(ControlPoint.Right).setPos(right, cy)
self.controlPoint(ControlPoint.Top).setPos(cx, top)
self.controlPoint(ControlPoint.Bottom).setPos(cx, bottom)
self.controlPoint(ControlPoint.TopLeft).setPos(left, top)
self.controlPoint(ControlPoint.TopRight).setPos(right, top)
self.controlPoint(ControlPoint.BottomLeft).setPos(left, bottom)
self.controlPoint(ControlPoint.BottomRight).setPos(right, bottom)
def __setActiveControl(self, control):
# type: (Optional[ControlPoint]) -> None
if self.__activeControl != control:
if self.__activeControl is not None:
self.__activeControl.positionChanged[QPointF].disconnect(
self.__activeControlMoved)
self.__activeControl = control
if control is not None:
control.positionChanged[QPointF].connect(
self.__activeControlMoved)
def __activeControlMoved(self, pos):
# type: (QPointF) -> None
# The active control point has moved, update the control
# rectangle
control = self.__activeControl
assert control is not None
pos = control.pos()
rect = QRectF(self.__rect)
margins = self.__margins
# TODO: keyboard modifiers and constraints.
anchor = control.anchor()
if anchor & ControlPoint.Top:
rect.setTop(pos.y() + margins.top())
elif anchor & ControlPoint.Bottom:
rect.setBottom(pos.y() - margins.bottom())
if anchor & ControlPoint.Left:
rect.setLeft(pos.x() + margins.left())
elif anchor & ControlPoint.Right:
rect.setRight(pos.x() - margins.right())
changed = self.__rect != rect
self.blockSignals(True)
self.setRect(rect)
self.blockSignals(False)
if changed:
self.rectEdited.emit(rect.normalized())
def boundingRect(self):
# type: () -> QRectF
return QRectF()