我使用pyqt4.8和python2.7

我創建QGraphicsView并插入QGraphicsScene.比View更大的場景,需要滾動.視圖有垂直和水平滾動,但我想通過鼠標中鍵滾動.

我創建鼠標事件功能,但運動到奇怪.

def mousePressEvent(self, event):

self.__mousePressPos = None

self.__mouseMovePos = None

if event.button() == Qt.MidButton:

self.__mousePressPos = event.globalPos()

self.__mouseMovePos = event.globalPos()

else:

super(MyView, self).mousePressEvent(event)

def mouseMoveEvent(self, event):

if event.buttons() == Qt.MidButton:

curPos = self.__mousePressPos - self.__mouseMovePos

self.centerOn(curPos.x(), curPos.y())

self.__mouseMovePos = globalPos

else:

super(MyView, self).mouseMoveEvent(event)

def mouseReleaseEvent(self, event):

if self.__mousePressPos is not None:

moved = event.globalPos() - self.__mousePressPos

if moved.manhattanLength() > 3:

event.ignore()

return

super(MyView, self).mouseReleaseEvent(event)

首先,場景移動與鼠標的移動不對應.我懷疑是視口的相對大小和場景的責任.以及舞臺的規模.

其次,我無法移動視口外的場景,它到達邊緣時停止.

讓第二個仍然可以容忍.讓它保持原樣,但如何計算正確移動的場景的正確偏移移動鼠標,無論它被捕獲的位置？

解決方法:

我的解決方案不是調用centerOn方法,而是使用QGraphicView的滾動條：

class MyView(QtGui.QGraphicsView):

def mousePressEvent(self, event):

if event.button() == Qt.MidButton: # or Qt.MiddleButton

self.__prevMousePos = event.pos()

else:

super(MyView, self).mousePressEvent(event)

def mouseMoveEvent(self, event):

if event.buttons() == Qt.MidButton: # or Qt.MiddleButton

offset = self.__prevMousePos - event.pos()

self.__prevMousePos = event.pos()

self.verticalScrollBar().setValue(self.verticalScrollBar().value() + offset.y())

self.horizontalScrollBar().setValue(self.horizontalScrollBar().value() + offset.x())

else:

super(MyView, self).mouseMoveEvent(event)

標簽：qgraphicsview,python,pyqt,mouseevent,qgraphicsscene

來源： https://codeday.me/bug/20190824/1709005.html

《新程序員》：云原生和全面數字化實踐50位技術專家共同創作，文字、視頻、音頻交互閱讀

總結

以上是生活随笔為你收集整理的qgraphicsview鼠标移动图片_如何在中间鼠标的QGraphicsView中滚动QGraphicsScene？的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。