QGraphicsItem のサブクラスがあり、そのインスタンスを「Control + LMB クリック」でシーンに追加したいと考えています。問題は、本来の 2 倍の座標の位置にアイテムが追加されることです。同時に、scene.addEllipse(...) で楕円を追加すると正常に動作します。
#!/usr/bin/env python
import sys
from PyQt4.QtCore import (QPointF, QRectF, Qt, )
from PyQt4.QtGui import (QApplication, QMainWindow, QGraphicsItem,
QGraphicsScene, QGraphicsView, QPen, QStyle)
MapSize = (512, 512)
class DraggableMark(QGraphicsItem):
def __init__(self, position, scene):
super(DraggableMark, self).__init__(None, scene)
self.setFlags(QGraphicsItem.ItemIsSelectable | QGraphicsItem.ItemIsMovable)
self.rect = QRectF(position.x(), position.y(), 15, 15)
self.setPos(position)
scene.clearSelection()
def boundingRect(self):
return self.rect
def paint(self, painter, option, widget):
pen = QPen(Qt.SolidLine)
pen.setColor(Qt.black)
pen.setWidth(1)
if option.state & QStyle.State_Selected:
pen.setColor(Qt.blue)
painter.setPen(pen)
painter.drawEllipse(self.rect)
class GraphicsScene(QGraphicsScene):
def __init__(self, parent=None):
super(GraphicsScene, self).__init__(parent)
self.setSceneRect(0, 0, *MapSize)
def mousePressEvent(self, event):
super(GraphicsScene, self).mousePressEvent(event)
if event.button() != Qt.LeftButton:
return
modifiers = QApplication.keyboardModifiers()
pos = event.scenePos()
if modifiers == Qt.ControlModifier:
print("Control + Click: (%d, %d)" % (pos.x(), pos.y()))
DraggableMark(pos, self)
self.addEllipse(QRectF(pos.x(), pos.y(), 10, 10))
else:
print("Click: (%d, %d)" % (pos.x(), pos.y()))
class MainWindow(QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.scene = GraphicsScene(self)
self.scene.addRect(QRectF(0, 0, *MapSize), Qt.red)
self.view = QGraphicsView()
self.view.setScene(self.scene)
self.view.resize(self.scene.width(), self.scene.height())
self.setCentralWidget(self.view)
if __name__ == "__main__":
app = QApplication(sys.argv)
window = MainWindow()
rect = QApplication.desktop().availableGeometry()
window.resize(int(rect.width()), int(rect.height()))
window.show()
app.exec_()
