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//! [0]
class SimpleItem(QGraphicsItem):
def boundingRect(self):
penWidth = 1.0
return QRectF(-10 - penWidth / 2, -10 - penWidth / 2,
20 + penWidth, 20 + penWidth)
def paint(self, painter, option, widget):
painter.drawRoundedRect(-10, -10, 20, 20, 5, 5)
//! [0]
//! [1]
class CustomItem(QGraphicsItem):
...
self.Type = QGraphicsItem.UserType + 1
def type(self):
# Enable the use of qgraphicsitem_cast with this item.
return self.Type
...
//! [1]
//! [2]
item.setCursor(Qt.IBeamCursor)
//! [2]
//! [3]
item.setCursor(Qt.IBeamCursor)
//! [3]
//! [4]
rect = QGraphicsRectItem()
rect.setPos(100, 100)
rect.sceneTransform().map(QPointF(0, 0))
# returns QPointF(100, 100)
rect.sceneTransform().inverted().map(QPointF(100, 100))
# returns QPointF(0, 0);
//! [4]
//! [5]
rect = QGraphicsRectItem()
rect.setPos(100, 100)
rect.deviceTransform(view.viewportTransform()).map(QPointF(0, 0))
# returns the item's (0, 0) point in view's viewport coordinates
rect.deviceTransform(view.viewportTransform()).inverted().map(QPointF(100, 100))
# returns view's viewport's (100, 100) coordinate in item coordinates
//! [5]
//! [6]
# Rotate an item 45 degrees around (0, 0)
item.rotate(45)
# Rotate an item 45 degrees around (x, y)
item.setTransform(QTransform().translate(x, y).rotate(45).translate(-x, -y))
//! [6]
//! [7]
# Scale an item by 3x2 from its origin
item.scale(3, 2)
# Scale an item by 3x2 from (x, y)
item.setTransform(QTransform().translate(x, y).scale(3, 2).translate(-x, -y))
//! [7]
//! [8]
def boundingRect(self):
penWidth = 1.0
return QRectF(-radius - penWidth / 2, -radius - penWidth / 2,
diameter + penWidth, diameter + penWidth)
//! [8]
//! [9]
def shape(self):
path = QPainterPath()
path.addEllipse(boundingRect())
return path
//! [9]
//! [10]
def paint(self, painter, option, widget):
painter.drawRoundedRect(-10, -10, 20, 20, 5, 5)
//! [10]
//! [11]
ObjectName = 0;
item = scene.itemAt(100, 50)
if len(item.data(ObjectName)) == 0:
if isinstance(ButtonItem, item):
item.setData(ObjectName, "Button")
//! [11]
//! [12]
scene = QGraphicsScene()
ellipse = scene.addEllipse(QRectF(-10, -10, 20, 20))
line = scene.addLine(QLineF(-10, -10, 20, 20))
line.installSceneEventFilter(ellipse)
# line's events are filtered by ellipse's sceneEventFilter() function.
ellipse.installSceneEventFilter(line)
# ellipse's events are filtered by line's sceneEventFilter() function.
//! [12]
//! [13]
def contextMenuEvent(self, event):
menu = QMenu()
removeAction = menu.addAction("Remove")
markAction = menu.addAction("Mark")
selectedAction = menu.exec(event.screenPos())
// ...
//! [13]
//! [14]
def __init__(self):
self.setAcceptDrops(true)
...
def dragEnterEvent(self, event):
event.setAccepted(event.mimeData().hasFormat("text/plain"))
//! [14]
//! [15]
def itemChange(self, change, value):
if change == ItemPositionChange && scene():
# value is the new position.
rect = scene().sceneRect()
if !rect.contains(value):
# Keep the item inside the scene rect.
value.setX(qMin(rect.right(), qMax(value.x(), rect.left())))
value.setY(qMin(rect.bottom(), qMax(value.y(), rect.top())))
return value
return QGraphicsItem.itemChange(self, change, value)
//! [15]
//! [16]
def setRadius(self, newRadius):
if radius != newRadius:
prepareGeometryChange()
radius = newRadius
//! [16]
//! [17]
# Group all selected items together
group = scene.createItemGroup(scene.selecteditems())
# Destroy the group, and delete the group item
scene.destroyItemGroup(group)
//! [17]
//! [QGraphicsItem type]
class CustomItem(QGraphicsItem):
...
self.Type = QGraphicsItem.UserType + 1
def type(self):
# Enable the use of qgraphicsitem_cast with this item.
return self.Type
...
//! [QGraphicsItem type]
//! [18]
class QGraphicsPathItem (QAbstractGraphicsShapeItem):
Type = 2
def type(self):
return QGraphicsPathItem.Type
# ...
//! [18]
//! [19]
xform = item.deviceTransform(view.viewportTransform())
deviceRect = xform.mapRect(rect).toAlignedRect()
view.viewport().scroll(dx, dy, deviceRect)
//! [19]
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