Current design shown below of QgraphicsView and QMainWindow class is an example of the design I have in a different software.
I had to add scrollbars to the QGraphicsView.
The original software has all mouse events handled in QMainWindow.
Questions: What is the way to draw on QGraphicsView through QMainWindow?
import sys
from PyQt4 import QtGui
from PyQt4 import QtCore
class Window(QtGui.QGraphicsView):
def __init__(self, parent=None):
QtGui.QGraphicsView.__init__(self, parent)
self.scene = QtGui.QGraphicsScene(self)
self.scene.setBackgroundBrush(QtGui.QBrush(QtCore.Qt.darkGray, QtCore.Qt.SolidPattern))
self.setScene(self.scene)
#self.setDragMode(QtGui.QGraphicsView.ScrollHandDrag)
self.setTransformationAnchor(QtGui.QGraphicsView.AnchorUnderMouse)
#self.viewport().setCursor(QtCore.Qt.CrossCursor)
self.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
self.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
print "sdsads"
def mousePressEvent(self, ev):
item = QtGui.QGraphicsTextItem("")
item.setPos(ev.x(), ev.y())
self.scene.addItem(item)
print "ev.x() ", ev.x()
class CityscapesLabelTool(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self, parent)
centralwidget = Window()
self.setCentralWidget(centralwidget)
centralwidget.scene.addPixmap(QtGui.QPixmap("exit.png"))
app = QtGui.QApplication(sys.argv)
GUI = CityscapesLabelTool()
GUI.show()
sys.exit(app.exec_())
In a QGraphicsView it is normal to add items to the scene, for example in case you want to draw a polygon you must use QGraphicsPolygonItem, also if you want to get correct points you must use QGraphicsScene instead of QGraphicsView.
In the following example you can indicate the polygon points by left clicking and finish the drawing with the right click.
import sys
from PyQt4 import QtCore, QtGui
class GraphicsScene(QtGui.QGraphicsScene):
def __init__(self, *args, **kwargs):
QtGui.QGraphicsScene.__init__(self, *args, **kwargs)
self.polygon = None
def mousePressEvent(self, ev):
if ev.button() == QtCore.Qt.RightButton:
self.polygon << ev.scenePos()
item = QtGui.QGraphicsPolygonItem(self.polygon)
item.setPen(QtGui.QPen(QtCore.Qt.red))
item.setBrush(QtGui.QBrush(QtCore.Qt.red))
self.addItem(item)
# or
# self.addPolygon(self.polygon, QtGui.QPen(QtCore.Qt.red), QtGui.QBrush(QtCore.Qt.red))
self.polygon = None
else:
if self.polygon is None:
self.polygon = QtGui.QPolygonF()
self.polygon << ev.scenePos()
class Window(QtGui.QGraphicsView):
def __init__(self, parent=None):
QtGui.QGraphicsView.__init__(self, parent)
self.scene =GraphicsScene(QtCore.QRectF(0, 0, 640, 480), self)
self.scene.setBackgroundBrush(QtGui.QBrush(QtCore.Qt.darkGray, QtCore.Qt.SolidPattern))
self.setScene(self.scene)
#self.setDragMode(QtGui.QGraphicsView.ScrollHandDrag)
self.setTransformationAnchor(QtGui.QGraphicsView.AnchorUnderMouse)
#self.viewport().setCursor(QtCore.Qt.CrossCursor)
self.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
self.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
class CityscapesLabelTool(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self, parent)
centralwidget = Window()
self.setCentralWidget(centralwidget)
centralwidget.scene.addPixmap(QtGui.QPixmap("exit.png"))
app = QtGui.QApplication(sys.argv)
GUI = CityscapesLabelTool()
GUI.show()
sys.exit(app.exec_())
Output:
You have an XY problem, where you are looking for the solution for a solution of the main problem without knowing that it is the correct one, according to what you comment your main problem is to add QScrollBar to the QMainWindow, and in that element you want to make drawings, so for that it is not necessary to use a QGraphicsView but a QScrollArea.
import sys
from PyQt4 import QtCore, QtGui
class Window(QtGui.QWidget):
def __init__(self, parent=None):
QtGui.QWidget.__init__(self, parent)
self.polygon = None
self.setFixedSize(640, 480)
self.pixmap = None
def mousePressEvent(self, ev):
if self.polygon is None:
self.polygon = QtGui.QPolygon()
self.polygon << ev.pos()
self.update()
def paintEvent(self, ev):
painter = QtGui.QPainter(self)
painter.fillRect(self.rect(), QtGui.QBrush(QtCore.Qt.darkGray, QtCore.Qt.SolidPattern))
painter.drawPixmap(QtCore.QPoint(0, 0), QtGui.QPixmap("exit.png"))
if self.polygon is not None:
painter.setPen(QtCore.Qt.blue)
painter.drawPolyline(self.polygon)
class CityscapesLabelTool(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self, parent)
scroll = QtGui.QScrollArea()
scroll.setBackgroundRole(QtGui.QPalette.Dark)
scroll.setWidget(Window())
scroll.setWidgetResizable(True)
self.setCentralWidget(scroll)
app = QtGui.QApplication(sys.argv)
GUI = CityscapesLabelTool()
GUI.show()
sys.exit(app.exec_())
Related
Q: I am trying to trigger a paint event inside the enter event in Qt but I am getting an error, basically can't call the painter inside the enter mouse event. What I need is to darken the image(as button) as I hover the mouse. Is this even possible? Thank you.
from PySide2 import QtWidgets
from PySide2 import QtGui
from PySide2 import QtCore
class PicButton(QtWidgets.QAbstractButton):
def __init__(self, pixmap, parent=None):
super(PicButton, self).__init__(parent)
self.pixmap = pixmap
def paintEvent(self, event):
painter = QtGui.QPainter(self)
painter.drawPixmap(event.rect(), self.pixmap)
painter.fillRect(event.rect(), QtGui.QBrush(QtGui.QColor (0,0,0,0)))
def enterEvent(self, event):
#error with the line below: 'PySide2.QtGui.QEnterEvent' object has no attribute 'rect'
#painter.fillRect(event.rect(), QtGui.QBrush(QtGui.QColor (0,0,0,128)))
print('hovering')
def sizeHint(self):
return self.pixmap.size()
window_wid = QtWidgets.QWidget()
vlayout_wid = QtWidgets.QVBoxLayout()
myPixmap = QtGui.QPixmap("image.jpg")
my_button = PicButton(myPixmap)
my_button.setCursor(QtGui.QCursor(QtCore.Qt.PointingHandCursor))
my_button.setMaximumSize(200,100)
vlayout_wid.addWidget(my_button)
window_wid.setLayout(vlayout_wid)
window_wid.show()
Ok, I solved the problem with underMouse() within the paintEvent. Not sure if it's the best solution but it's working now. Just wish I was able to brighten the image instead of darkening.
from PySide2 import QtWidgets
from PySide2 import QtGui
from PySide2 import QtCore
class PicButton(QtWidgets.QAbstractButton):
def __init__(self, pixmap, parent=None):
super(PicButton, self).__init__(parent)
self.pixmap = pixmap
self.pressed.connect(self.update)
self.released.connect(self.update)
def paintEvent(self, event):
#pix = self.pixmap_hover if self.underMouse() else self.pixmap
painter = QtGui.QPainter(self)
painter.drawPixmap(event.rect(), self.pixmap)
pix = painter.fillRect(event.rect(), QtGui.QBrush(QtGui.QColor (0,0,0,128))) if self.underMouse() else self.pixmap
def enterEvent(self, event):
self.update()
def leaveEvent(self, event):
self.update()
def sizeHint(self):
return QtCore.QSize(200, 100)
window_wid = QtWidgets.QWidget()
vlayout_wid = QtWidgets.QVBoxLayout()
pixmap = QtGui.QPixmap("image.jpg")
my_button = PicButton(pixmap)
my_button.setCursor(QtGui.QCursor(QtCore.Qt.PointingHandCursor))
#my_button.setMaximumSize(200,100)
vlayout_wid.addWidget(my_button)
window_wid.setLayout(vlayout_wid)
window_wid.show()
I have recently created a widget with Qpaint, which I want to pass value to it, at the same time force the Qpaint Widget to draw from input values. The idea is to define a data value from a Qdialog and pass it to main widget, and pass the value to Qpaint Widget class. I would like to have, when user clicks on the button 'Getting values' a dialog widget would appear and insert some int values, then pass it to main Widget. from there pass value to correct class Paint. Which would draw and display the result. I tried with Qlabel, to assign value first to Qlabel or QlineEdit,
class Button(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Button, self).__init__(parent)
---------
self.value = QtWidgets.QLabel()
--------
Then inside the paint class call the value or text of those. then assign it to Qpaint event. But seems does not work.'
class Paint(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Paint, self).__init__(parent)
self.button = Button()
self.Value = self.button.value
---------
painter.drawRect(100,100,250,250) <----- instead of value 250 having self.Value
The code Main.py
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
from datainput import *
class Foo(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Foo, self).__init__(parent)
self.setGeometry(QtCore.QRect(200, 100, 800, 800))
self.button = Button()
self.paint = Paint()
self.lay = QtWidgets.QVBoxLayout()
self.lay.addWidget(self.paint)
self.lay.addWidget(self.button)
self.setLayout(self.lay)
class Paint(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Paint, self).__init__(parent)
self.button = Button()
self.Value = self.button.value
self.setBackgroundRole(QtGui.QPalette.Base)
self.setAutoFillBackground(True)
def paintEvent(self, event):
self.pen = QtGui.QPen()
self.brush = QtGui.QBrush( QtCore.Qt.gray, QtCore.Qt.Dense7Pattern)
painter = QtGui.QPainter(self)
painter.setRenderHint(QtGui.QPainter.Antialiasing)
painter.setPen(self.pen)
painter.setBrush(self.brush)
painter.drawRect(100,100,250,250)
painter.setBrush(QtGui.QBrush())
class Button(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Button, self).__init__(parent)
getbutton = QtWidgets.QPushButton('Getting values')
Alay = QtWidgets.QVBoxLayout(self)
Alay.addWidget(getbutton)
self.value = QtWidgets.QLabel()
getbutton.clicked.connect(self.getbuttonfunc)
def getbuttonfunc(self):
subwindow=Dinput()
subwindow.setWindowModality(QtCore.Qt.ApplicationModal)
if subwindow.exec_() == QtWidgets.QDialog.Accepted:
self._output = subwindow.valueEdit.text()
return self.value.setText(self._output)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = Foo()
w.show()
sys.exit(app.exec_())
Input Qdialog code, datainput.py
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class Dinput(QtWidgets.QDialog):
def __init__(self, parent=None):
super(Dinput, self).__init__(parent)
valuelabel = QtWidgets.QLabel('Input: ')
self.valueEdit = QtWidgets.QLineEdit()
buttonBox = QtWidgets.QDialogButtonBox()
buttonBox.setStandardButtons(QtWidgets.QDialogButtonBox.Cancel|QtWidgets.QDialogButtonBox.Ok)
buttonBox.accepted.connect(self.accept)
buttonBox.rejected.connect(self.close)
self.Alay = QtWidgets.QHBoxLayout()
self.Alay.addWidget(valuelabel)
self.Alay.addWidget(self.valueEdit)
self.Blay = QtWidgets.QVBoxLayout()
self.Blay.addLayout(self.Alay)
self.Blay.addWidget(buttonBox)
self.setLayout(self.Blay)
def closeEvent(self, event):
super(Dinput, self).closeEvent(event)
def accept(self):
super(Dinput, self).accept()
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = Dinput()
w.show()
sys.exit(app.exec_())
Visualization
I appreciate any help. Thankssss
datainput is irrelevant, your task is only to obtain a number so for space question I will not use it and instead I will use QInputDialog::getInt(). Going to the problem, the strategy in these cases where the value can be obtained at any time is to notify the change to the other view through a signal, in the slot that receives the value is to update a variable that stores the value and call update so that it calls when necessary to paintEvent, and in the paintEvent use the variable that stores the value.
import sys
from PyQt5 import QtCore, QtGui, QtWidgets
class Foo(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Foo, self).__init__(parent)
self.setGeometry(QtCore.QRect(200, 100, 800, 800))
self.button = Button()
self.paint = Paint()
self.button.valueChanged.connect(self.paint.set_size_square)
self.lay = QtWidgets.QVBoxLayout(self)
self.lay.addWidget(self.paint)
self.lay.addWidget(self.button)
class Paint(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Paint, self).__init__(parent)
self.setBackgroundRole(QtGui.QPalette.Base)
self.setAutoFillBackground(True)
self._size_square = 250
#QtCore.pyqtSlot(int)
def set_size_square(self, v):
self._size_square = v
self.update()
def paintEvent(self, event):
pen = QtGui.QPen()
brush = QtGui.QBrush( QtCore.Qt.gray, QtCore.Qt.Dense7Pattern)
painter = QtGui.QPainter(self)
painter.setRenderHint(QtGui.QPainter.Antialiasing)
painter.setPen(pen)
painter.setBrush(brush)
r = QtCore.QRect(QtCore.QPoint(100, 100), self._size_square*QtCore.QSize(1, 1))
painter.drawRect(r)
class Button(QtWidgets.QWidget):
valueChanged = QtCore.pyqtSignal(int)
def __init__(self, parent=None):
super(Button, self).__init__(parent)
getbutton = QtWidgets.QPushButton('Getting values')
Alay = QtWidgets.QVBoxLayout(self)
Alay.addWidget(getbutton)
self.value = QtWidgets.QLabel()
getbutton.clicked.connect(self.getbuttonfunc)
#QtCore.pyqtSlot()
def getbuttonfunc(self):
number, ok = QtWidgets.QInputDialog.getInt(self, self.tr("Set Number"),
self.tr("Input:"), 1, 1)
if ok:
self.valueChanged.emit(number)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = Foo()
w.show()
sys.exit(app.exec_())
I have a scene like this
class Scene(QtWidgets.QGraphicsScene):
def __init__(self, parent=None):
super(Scene, self).__init__(parent)
def mousePressEvent(self, event):
print('scene pressed')
self.wid = MyRect(event.pos(), event.pos())
self.addItem(self.wid)
self.wid.show()
I would like class MyRect(QtWidgets.QGraphicsRectItem) with painter, mouse event and so on to be a draggable rectangle.
all stuff in MyRect
So then I could have many Rectangle to the scene and even after draw line between them and so on (kind of diagram app), but keeping objects related editable options in MyRect, MyLine , ....
I thought :
class MyRect(QtWidgets.QGraphicsRectItem):
def __init__(self, begin, end, parent=None):
super().__init__(parent)
self.begin = begin
self.end = end
def paintEvent(self, event):
print('painting')
qp = QtGui.QPainter(self)
qp.drawRect(QtCore.QRect(self.begin, self.end))
def mousePressEvent(self, event):
self.begin = event.pos()
self.end = event.pos()
self.update()
def mouseMoveEvent(self, event):
self.end = event.pos()
self.update()
def mouseReleaseEvent(self, event):
self.begin = event.pos()
self.end = event.pos()
self.update()
But I does not work (paint event not initiated whereas mousepressed event in scene is intiated)
I did not find what I wanted through the web so started totry do it by myself. I'm pretty sure it is a must known starting point but I cannot find it
First of all a QGraphicsItem is not a QWidget, so it has those events and does not handle them directly, that's what QGraphicsView and QGraphicsScene do. For example you say that you want to have a moveable rectangle because that task is simple is QGraphicsView, it is not necessary to overwrite:
from PyQt5 import QtCore, QtWidgets
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
scene = QtWidgets.QGraphicsScene(self)
view = QtWidgets.QGraphicsView(scene)
self.setCentralWidget(view)
rect_item = QtWidgets.QGraphicsRectItem(QtCore.QRectF(0, 0, 100, 100))
rect_item.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable, True)
scene.addItem(rect_item)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
w.resize(640, 480)
w.show()
sys.exit(app.exec_())
If you want to change the way you paint the rectangle you must overwrite the paint() method as shown below:
from PyQt5 import QtCore, QtGui, QtWidgets
class RectItem(QtWidgets.QGraphicsRectItem):
def paint(self, painter, option, widget=None):
super(RectItem, self).paint(painter, option, widget)
painter.save()
painter.setRenderHint(QtGui.QPainter.Antialiasing)
painter.setBrush(QtCore.Qt.red)
painter.drawEllipse(option.rect)
painter.restore()
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
scene = QtWidgets.QGraphicsScene(self)
view = QtWidgets.QGraphicsView(scene)
self.setCentralWidget(view)
rect_item = RectItem(QtCore.QRectF(0, 0, 100, 100))
rect_item.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable, True)
scene.addItem(rect_item)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
w.resize(640, 480)
w.show()
sys.exit(app.exec_())
Update:
from PyQt5 import QtCore, QtGui, QtWidgets
class GraphicsScene(QtWidgets.QGraphicsScene):
def __init__(self, parent=None):
super(GraphicsScene, self).__init__(QtCore.QRectF(-500, -500, 1000, 1000), parent)
self._start = QtCore.QPointF()
self._current_rect_item = None
def mousePressEvent(self, event):
if self.itemAt(event.scenePos(), QtGui.QTransform()) is None:
self._current_rect_item = QtWidgets.QGraphicsRectItem()
self._current_rect_item.setBrush(QtCore.Qt.red)
self._current_rect_item.setFlag(QtWidgets.QGraphicsItem.ItemIsMovable, True)
self.addItem(self._current_rect_item)
self._start = event.scenePos()
r = QtCore.QRectF(self._start, self._start)
self._current_rect_item.setRect(r)
super(GraphicsScene, self).mousePressEvent(event)
def mouseMoveEvent(self, event):
if self._current_rect_item is not None:
r = QtCore.QRectF(self._start, event.scenePos()).normalized()
self._current_rect_item.setRect(r)
super(GraphicsScene, self).mouseMoveEvent(event)
def mouseReleaseEvent(self, event):
self._current_rect_item = None
super(GraphicsScene, self).mouseReleaseEvent(event)
class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
scene =GraphicsScene(self)
view = QtWidgets.QGraphicsView(scene)
self.setCentralWidget(view)
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
w.resize(640, 480)
w.show()
sys.exit(app.exec_())
Due to some restrictions image has to be in the class QMainWindow and scrollbars have to be the QGraphicsView class.
This means that I have to add image in QGraphicsView class through QMainWindow class. "exit.png" exists in the folder from where I run this code.
What is the proper way to add this picture?
import sys
from PyQt4 import QtGui
from PyQt4 import QtCore
class Window(QtGui.QGraphicsView):
def __init__(self, parent=None):
QtGui.QGraphicsView.__init__(self, parent)
self.scene = QtGui.QGraphicsScene(self)
self.scene.setBackgroundBrush(QtGui.QBrush(QtCore.Qt.darkGray, QtCore.Qt.SolidPattern))
self.setScene(self.scene)
self.setDragMode(QtGui.QGraphicsView.ScrollHandDrag)
self.setTransformationAnchor(QtGui.QGraphicsView.AnchorUnderMouse)
self.viewport().setCursor(QtCore.Qt.CrossCursor)
self.setHorizontalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
self.setVerticalScrollBarPolicy(QtCore.Qt.ScrollBarAlwaysOn)
print "sdsads"
class CityscapesLabelTool(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self, parent)
centralwidget = Window()
self.setCentralWidget(centralwidget)
centralwidget.scene.image = QtGui.QImage("exit.png")
app = QtGui.QApplication(sys.argv)
GUI = CityscapesLabelTool()
GUI.show()
sys.exit(app.exec_())
For this case the solution is to use a QGraphicsPixmapItem:
class CityscapesLabelTool(QtGui.QMainWindow):
def __init__(self, parent=None):
QtGui.QMainWindow.__init__(self, parent)
centralwidget = Window()
self.setCentralWidget(centralwidget)
centralwidget.scene.addPixmap(QtGui.QPixmap("exit.png"))
# or
# item = QtGui.QGraphicsPixmapItem(QtGui.QPixmap("exit.png"))
# centralwidget.scene.addItem(item)
I'm trying to change the background image of the QMainWindow central widget. The QMainWindow's background is fairly easy to change but I can't get the same result with it's central widget. What I tried is the code
self.mdi = QMdiArea()
self.options_window = Options()
self.central_widget = QStackedWidget()
self.mdi.setStyleSheet("{background-image: url(ninja.png);}")
self.setCentralWidget(self.central_widget)
self.central_widget.addWidget(self.mdi)
self.central_widget.addWidget(self.options_window)
self.central_widget.setCurrentWidget(self.mdi)
I also tried with this one
self.mdi = QMdiArea()
self.options_window = Options()
self.central_widget = QStackedWidget()
self.central_widget.setStyleSheet("{background-image: url(ninja.png);}")
self.setCentralWidget(self.central_widget)
self.central_widget.addWidget(self.mdi)
self.central_widget.addWidget(self.options_window)
self.central_widget.setCurrentWidget(self.mdi)
Could anyone give me a light in this problem?
To change the background image of a QWidget you should override the paintEvent method, in your case yours in a QStackedWidget, we create a class that inherits from this:
class StackedWidget(QStackedWidget):
def __init__(self, parent=None):
QStackedWidget.__init__(self, parent=parent)
def paintEvent(self, event):
painter = QPainter(self)
painter.drawPixmap(self.rect(), QPixmap("ninja.png"))
QStackedWidget.paintEvent(self, event)
And then you change:
self.central_widget = QStackedWidget()
to:
self.central_widget = StackedWidget()
Example:
import sys
from PyQt5.QtWidgets import *
from PyQt5.QtGui import *
class StackedWidget(QStackedWidget):
def __init__(self, parent=None):
QStackedWidget.__init__(self, parent=parent)
def paintEvent(self, event):
painter = QPainter(self)
painter.drawPixmap(self.rect(), QPixmap("image.png"))
QStackedWidget.paintEvent(self, event)
class MainWindow(QMainWindow):
def __init__(self, parent=None):
QMainWindow.__init__(self, parent=parent)
self.setCentralWidget(StackedWidget())
if __name__ == '__main__':
app = QApplication(sys.argv)
w = MainWindow()
w.show()
sys.exit(app.exec_())
Screenshot:
The case of QStackedWidget is a special case since this is not shown, this serves to show other widgets, to those widgets you must change the background image.
From your code, the first widget they attach is a QMdiArea, this is also a special case since it has a viewport and this should be changed.
class MdiArea(QMdiArea):
def __init__(self, parent=None):
QMdiArea.__init__(self, parent=parent)
def paintEvent(self, event):
QMdiArea.paintEvent(self, event)
painter = QPainter(self.viewport())
painter.drawPixmap(self.rect(), QPixmap("image.png"))
In your code change:
self.mdi = QMdiArea()
to:
self.mdi = MdiArea()
Screenshots: