Python PyQt事件发生两次
我正在尝试实现从Python PyQt事件发生两次,python,qt,pyqt,signals,Python,Qt,Pyqt,Signals,我正在尝试实现从QListWidget到QGraphicsView的拖放项。我从QGraphicsView继承了自己的类MooView,并封装了dragMove、dragEnter和drop事件。但在测试这一点时,我注意到每个事件都会出现两次 这是我的MooView代码: from PyQt4 import QtCore, QtGui class MooView(QtGui.QGraphicsView): def __init__(self, parent = None):
QListWidget
到QGraphicsView
的拖放项。我从QGraphicsView
继承了自己的类MooView
,并封装了dragMove
、dragEnter
和drop
事件。但在测试这一点时,我注意到每个事件都会出现两次
这是我的MooView
代码:
from PyQt4 import QtCore, QtGui
class MooView(QtGui.QGraphicsView):
def __init__(self, parent = None):
QtGui.QGraphicsView.__init__(self, parent)
self.handlers = {}
self.handlers['dragEnter'] = []
self.handlers['dragEnter'].append(super(MooView, self).dragEnterEvent)
self.handlers['dragLeave'] = []
self.handlers['dragLeave'].append(super(MooView, self).dragLeaveEvent)
self.handlers['dragMove'] = []
self.handlers['dragMove'].append(super(MooView, self).dragMoveEvent)
self.handlers['drop'] = []
self.handlers['drop'].append(super(MooView, self).dropEvent)
def addDragEnterHandler(self, handler):
self.handlers['dragEnter'].append(handler)
def removeDragEnterHandler(self, handler):
self.handlers['dragEnter'].remove(handler)
def addDragLeaveHandler(self, handler):
self.handlers['dragLeave'].append(handler)
def removeDragLeaveHandler(self, handler):
self.handlers['dragLeave'].remove(handler)
def addDragMoveHandler(self, handler):
self.handlers['dragMove'].append(handler)
def removeDragMoveHandler(self, handler):
self.handlers['dragMove'].remove(handler)
def addDropHandler(self, handler):
self.handlers['drop'].append(handler)
def removeDropHandler(self, handler):
self.handlers['drop'].remove(handler)
# handlers
def dragEnterEvent(self, arg):
#res = super(MooView, self).dragEnterEvent(arg)
for h in self.handlers['dragEnter']:
h(arg)
#return res
def dragLeaveEvent(self, arg):
#res = super(MooView, self).dragLeaveEvent(arg)
for h in self.handlers['dragLeave']:
h(arg)
#return res
def dragMoveEvent(self, arg):
#res = super(MooView, self).dragMoveEvent(arg)
for h in self.handlers['dragMove']:
h(arg)
#return res
def dropEvent(self, arg):
#res = super(MooView, self).dropEvent(arg)
for h in self.handlers['drop']:
h(arg)
#return res
这就是我运行核心的方式:
import sys
from PyQt4 import QtCore, QtGui, QtOpenGL
from window import Ui_MainWindow
class Main(QtGui.QMainWindow):
def __init__(self, parent = None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
self.setWindowTitle('Hello, Qt!')
self.scene = QtGui.QGraphicsScene()
self.ui.workspace_view.setScene(self.scene)
rect = QtCore.QRectF(0, 0, 1000, 1000)
self.scene.setSceneRect(0, 0, rect.width(), rect.height())
self.ui.workspace_view.setViewport(QtOpenGL.QGLWidget())
icon = QtGui.QIcon(QtGui.QPixmap(":/Images/50.png"))
text = "50's element"
item = QtGui.QListWidgetItem(icon, text)
self.ui.element_list.addItem(item)
icon = QtGui.QIcon(QtGui.QPixmap(":/Images/40.png"))
text = "40's element"
item = QtGui.QListWidgetItem(icon, text)
self.ui.element_list.addItem(item)
self.ui.workspace_view.addDragEnterHandler(self.workspace_item_drag_enter)
self.ui.workspace_view.addDragMoveHandler(self.workspace_item_drag_move)
self.ui.workspace_view.addDropHandler(self.workspace_item_dropped)
def workspace_item_drag_move(self, e):
#print("item drag move")
e.accept()
def workspace_item_drag_enter(self, e):
print("item drag enter")
e.accept()
def workspace_item_dropped(self, e):
print("item dropped")
if (__name__ == "__main__"):
app = QtGui.QApplication(sys.argv)
myApp = Main()
myApp.show()
sys.exit(app.exec_())
拖放项目时,“项目拖放输入”和“项目拖放”行在终端中各打印两次,例如:
item drag enter
item drag enter
item dropped
item dropped
问题是:如何修复它???正如我在网上读到的,在某些情况下,
QGraphicsView
可以将事件传递给它的qgraphicscene
。这里也是这样:当我从qgraphicscene
继承我的类,并将其用作QGraphicsView
的默认值时(将MooView
替换为QGraphicsView
;详细阅读此答案的其余部分),它按照我的预期工作
现在我有两个源代码部分:moographicscene.py
和main.py
。以下分别是:
from PyQt4 import QtCore, QtGui
class MooGraphicsScene(QtGui.QGraphicsScene):
def __init__(self, parent = None):
QtGui.QGraphicsScene.__init__(self, parent)
def dragMoveEvent(selfs, e):
pass
def dropEvent(self, e):
print("Drop fired!")
def dragEnterEvent(self, e):
e.accept()
print("Drag entered!")
还有这个:
import sys
from PyQt4 import QtCore, QtGui, QtOpenGL
from window import Ui_MainWindow
from MooGraphicsScene import MooGraphicsScene
class Main(QtGui.QMainWindow):
def __init__(self, parent = None):
QtGui.QWidget.__init__(self, parent)
self.ui = Ui_MainWindow()
self.ui.setupUi(self)
self.setWindowTitle('Hello, Qt!')
# Setup Workspace
self.scene = MooGraphicsScene()
self.ui.workspace_view.setScene(self.scene)
rect = QtCore.QRectF(0, 0, 1000, 1000)
self.scene.setSceneRect(0, 0, rect.width(), rect.height())
icon = QtGui.QIcon(QtGui.QPixmap(":/Images/50.png"))
text = "50's element"
item = QtGui.QListWidgetItem(icon, text)
self.ui.element_list.addItem(item)
icon = QtGui.QIcon(QtGui.QPixmap(":/Images/40.png"))
text = "40's element"
item = QtGui.QListWidgetItem(icon, text)
self.ui.element_list.addItem(item)
if (__name__ == "__main__"):
app = QtGui.QApplication(sys.argv)
myApp = Main()
myApp.show()
sys.exit(app.exec_())
希望,这会帮助别人