Pyside2 如何移动盒子?

Question

如果我按左键移动鼠标，我想移动我的 SimpleItem 对象。如果我按下对象，我已经成功地获得了鼠标光标的位置。但我不知道如何将项目移动到那个位置。你能帮我吗？

import sys
from PySide2 import QtGui, QtWidgets, QtCore

class SimpleItem(QtWidgets.QGraphicsItem):
def __init__(self):
QtWidgets.QGraphicsItem.__init__(self)
self.location = 1.0
def boundingRect(self):
penWidth = 1.0
return QtCore.QRectF(-10 - penWidth / 2, -10 - penWidth / 2,
20 + penWidth, 20 + penWidth)
def paint(self, painter, option, widget):
rect = self.boundingRect()
painter.drawRect(rect)
def mousePressEvent(self, event):
print("hello")
def mouseMoveEvent(self, event):
print(event.pos())

if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
scene = QtWidgets.QGraphicsScene()
item = SimpleItem()
scene.addItem(item)
view = QtWidgets.QGraphicsView(scene)
view.show()
sys.exit(app.exec_())

Answer 1

在QGraphicsXXXItem的情况下，没有必要覆盖任何方法来启用移动，只需启用标志QGraphicsItem::ItemIsMovable即可。

import sys
from PySide2 import QtGui, QtWidgets, QtCore

class SimpleItem(QtWidgets.QGraphicsItem):
def __init__(self):
QtWidgets.QGraphicsItem.__init__(self)
self.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable, True)
def boundingRect(self):
penWidth = 1.0
return QtCore.QRectF(-10 - penWidth / 2, -10 - penWidth / 2,
20 + penWidth, 20 + penWidth)
def paint(self, painter, option, widget):
rect = self.boundingRect()
painter.drawRect(rect)

if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
scene = QtWidgets.QGraphicsScene()
item = SimpleItem()
scene.addItem(item)
view = QtWidgets.QGraphicsView(scene)
view.show()
sys.exit(app.exec_())