我如何两次应用BlurEffect（QtWidgets.QGraphicsBlurEffect）？

Question

我有此代码

import sys                                                         # +++
from PyQt5.QtCore import Qt, QUrl
from PyQt5.QtWidgets import QApplication, QWidget, QMainWindow, QVBoxLayout, QLabel
from PyQt5.QtQml import QQmlApplicationEngine
from PyQt5.QtCore import (QCoreApplication, QMetaObject, QObject, QPoint,
    QRect, QSize, QUrl, Qt)
from PyQt5 import QtCore, QtGui, QtWidgets


'''
from PySide2.QtCore import Qt, QUrl
from PySide2.QtWidgets import QApplication, QWidget, QMainWindow, QVBoxLayout, QLabel
from PySide2.QtQml import QQmlApplicationEngine
from PySide2.QtCore import (QCoreApplication, QMetaObject, QObject, QPoint,
    QRect, QSize, QUrl, Qt)
from PySide2 import QtCore, QtGui, QtWidgets
'''



class BlurEffect(QtWidgets.QGraphicsBlurEffect):
    effectRect = None

    def setEffectRect(self, rect):
        self.effectRect = rect
        self.update()

    def draw(self, qp):
        if self.effectRect is None or self.effectRect.isNull():
            # no valid effect rect to be used, use the default implementation
            super().draw(qp)
            print('bao')
        else:
            qp.save()
            # clip the drawing so that it's restricted to the effectRect
            qp.setClipRect(self.effectRect)
            # call the default implementation, which will draw the effect
            super().draw(qp)
            # get the full region that should be painted
            fullRegion = QtGui.QRegion(qp.viewport())
            # and subtract the effect rectangle
            fullRegion -= QtGui.QRegion(self.effectRect)
            qp.setClipRegion(fullRegion)
            # draw the *source*, which has no effect applied
            self.drawSource(qp)
            qp.restore()


class Window(QtWidgets.QWidget):
    def __init__(self):
        super().__init__()

        background = QtGui.QPixmap('background.png')

        # apply a background to this widget, note that this only serves for the
        # graphics effect to know what's outside the boundaries
        p = self.palette()
        p.setBrush(p.Window, QtGui.QBrush(background))
        self.setPalette(p)

        self.resize(background.size())

        # this layout is only for the child "sub" widget
        mainLayout = QtWidgets.QVBoxLayout(self)
        mainLayout.setContentsMargins(0, 0, 0, 0)

        # the "sub" widget, that contains the main interface
        self.subWidget = QtWidgets.QWidget()
        mainLayout.addWidget(self.subWidget)
        # set the background for the subwidget; note that we can't use setPalette()
        # because palette and fonts are inherited by children; using ".QWidget"
        # we ensure that the background is only applied to the subwidget
        self.subWidget.setStyleSheet('''
            .QWidget {
                background-image: url(background.png);
            }
        ''')

        # some random widgets
        subLayout = QtWidgets.QGridLayout(self.subWidget)
        for row in range(3):
            for col in range(3):
                btn = QtWidgets.QPushButton()
                subLayout.addWidget(btn, row, col)

        btn.setText('Open menu')
        btn.setFocus()
        btn.clicked.connect(self.openMenu)

        # create an instance of our effect subclass, and apply it to the subwidget
        self.effect = BlurEffect()
        self.subWidget.setGraphicsEffect(self.effect)
        self.effect.setEnabled(False)
        self.effect.setBlurRadius(10)









        # create the menu container, that *HAS* to have this main widget as parent
        self.topMenu = QtWidgets.QWidget(self)
        self.topMenu.setVisible(False)
        self.topMenu.setFixedWidth(200)
        # move the menu outside the window left margin
        self.topMenu.move(-self.topMenu.width(), 0)

        menuLayout = QtWidgets.QVBoxLayout(self.topMenu)
        menuLayout.addSpacing(20)
        for b in range(4):
            btn = QtWidgets.QPushButton('Button {}'.format(b + 1))
            menuLayout.addWidget(btn)

        menuLayout.addSpacing(10)

        closeButton = QtWidgets.QPushButton('Close menu')
        menuLayout.addWidget(closeButton)
        closeButton.clicked.connect(self.closeMenu)
        # a stretch to ensure that the items are always aligned on top
        menuLayout.addStretch(1)

        # an animation that will move the menu laterally
        self.menuAnimation = QtCore.QVariantAnimation()
        self.menuAnimation.setDuration(500)
        self.menuAnimation.setEasingCurve(QtCore.QEasingCurve.OutQuart)
        self.menuAnimation.setStartValue(-self.topMenu.width())
        self.menuAnimation.setEndValue(0)
        self.menuAnimation.valueChanged.connect(self.resizeMenu)
        self.menuAnimation.finished.connect(self.animationFinished)

        # a simple transparent widget that is used to hide the menu when
        # clicking outside it; the event filter is to capture click events
        # it may receive
        self.clickGrabber = QtWidgets.QWidget(self)
        self.clickGrabber.installEventFilter(self)
        self.clickGrabber.setVisible(False)

    def resizeMenu(self, value):
        # move the menu and set its geometry to the effect
        self.topMenu.move(value, 0)
        self.effect.setEffectRect(self.topMenu.geometry())

    def openMenu(self):
        if self.topMenu.x() >= 0:
            # the menu is already visible
            return
        # ensure that the menu starts hidden (that is, with its right border
        # aligned to the left of the main widget)
        self.topMenu.move(-self.topMenu.width(), 0)
        self.topMenu.setVisible(True)
        self.topMenu.setFocus()

        # enable the effect, set the forward direction for the animation, and
        # start it; it's important to set the effect rectangle here too, otherwise
        # some flickering might show at the beginning
        self.effect.setEffectRect(self.topMenu.geometry())
        self.effect.setEnabled(True)
        self.menuAnimation.setDirection(QtCore.QVariantAnimation.Forward)
        self.menuAnimation.start()

        # "show" the grabber (it's invisible, but it's there) and resize it
        # to cover the whole window area
        self.clickGrabber.setGeometry(self.rect())
        self.clickGrabber.setVisible(True)
        # ensure that it is stacked under the menu and above everything else
        self.clickGrabber.stackUnder(self.topMenu)

    def closeMenu(self):
        # in case that the menu has changed its size, set again the "start" value
        # to its negative width, then set the animation direction to backwards
        # and start it
        self.menuAnimation.setStartValue(-self.topMenu.width())
        self.menuAnimation.setDirection(QtCore.QVariantAnimation.Backward)
        self.menuAnimation.start()
        # hide the click grabber
        self.clickGrabber.setVisible(False)

    def animationFinished(self):
        # if the animation has ended and the direction was backwards it means that
        # the menu has been closed, hide it and disable the effect
        if self.menuAnimation.direction() == QtCore.QVariantAnimation.Backward:
            self.topMenu.hide()
            self.effect.setEnabled(False)

    def focusNextPrevChild(self, next):
        if self.topMenu.isVisible():
            # a small hack to prevent tab giving focus to widgets when the
            # menu is visible
            return False
        return super().focusNextPrevChild(next)

    def eventFilter(self, source, event):
        if source == self.clickGrabber and event.type() == QtCore.QEvent.MouseButtonPress:
            # the grabber has been clicked, close the menu
            self.closeMenu()
        return super().eventFilter(source, event)

    def resizeEvent(self, event):
        super().resizeEvent(event)
        # always set the menu height to that of the window
        self.topMenu.setFixedHeight(self.height())
        # resize the grabber to the window rectangle, even if it's invisible
        self.clickGrabber.setGeometry(self.rect())
        if self.topMenu.isVisible():
            # resize the effect rectangle
            self.effect.setEffectRect(self.topMenu.geometry())



if __name__ == "__main__":
    app = QtWidgets.QApplication(sys.argv)

    w = Window()
    w.resize(640, 570)  
    w.show()
    sys.exit(app.exec_())

我需要能够一次将模糊效果应用于多个小部件

问题是我添加时

    self.effect2 = BlurEffect()
    self.subWidget.setGraphicsEffect(self.effect2)
    self.effect2.setEnabled(False)
    self.effect2.setBlurRadius(10)

之后

    self.effect = BlurEffect()
    self.subWidget.setGraphicsEffect(self.effect)
    self.effect.setEnabled(False)
    self.effect.setBlurRadius(10)

我收到此错误

跟踪（最近一次通话）：文件openMenu中的“ C：\ Users \ user \ Desktop \ test \ widgets \ menu.py”行157self.effect.setEffectRect（self.topMenu.geometry（））文件“ C：\ Users \ user \ Desktop \ test \ widgets \ menu.py”，第15行，在setEffectRectself.update（）RuntimeError：类型为BlurEffect的包装的C / C ++对象已被删除]

有人知道如何解决此问题吗？

photoshop

Answer 1