PyQt - can I add a QWidget in paintEvent? - pyqt

Question

I am using PyQt to make an application that, amongst other things, shows information in a simple graphical diagram.
I have done this as a QWidget and reimplemented the paintEvent method to do the drawing. A small and very cut-down example is show below.
from PyQt4.QtCore import *
from PyQt4.QtGui import * # sloppy, I know, but done for speed! :-)
class Example(QMainWindow):
def __init__(self,parent=None):
super(Example,self).__init__(parent)
self.init_ui()
def init_ui(self):
base=QWidget()
layout=QVBoxLayout(base)
self.diagram=Diagram()
layout.addWidget(self.diagram)
self.setCentralWidget(base)
class Diagram(QWidget):
def __init__(self,parent=None):
super(Diagram,self).__init__(parent)
self.width=360
self.height=120
self.leftMargin=10
self.topMargin=10
def paintEvent(self,event=None):
painter=QPainter(self)
painter.setWindow(self.leftMargin,self.topMargin,self.width,self.height)
self.drawConnection(painter, 40, 25, 40, 90)
self.drawConnection(painter, 40, 90, 40, 110)
self.drawConnection(painter, 40, 110, 200, 100)
self.drawItem(painter, 40, 40)
self.drawItem(painter, 40, 90)
self.drawState(painter,200,100)
def drawConnection(self,painter,x0,y0,x1,y1):
pen=QPen()
pen.setWidth(4)
pen.setColor(QColor(50,50,200))
painter.setPen(pen)
painter.drawLine(x0,y0,x1,y1)
def drawItem(self,painter,x,y):
w=40
h=30
r=QRectF(x-(w/2),y-(h/2),w,h)
painter.drawRoundedRect(r,5.0,5.0)
grad=QLinearGradient(QPointF(15.0,20.0),QPointF(30.0,30.0))
pen=QPen()
pen.setWidth(2)
pen.setColor(QColor(10,10,10))
painter.setPen(pen)
brush=QBrush(QColor(0,200,10))
painter.setBrush(brush)
painter.drawRoundedRect(r,5.0,5.0)
def drawState(self,painter,x,y):
w=80
h=60
r=QRectF(x-(w/2),y-(h/2),w,h)
pen=QPen()
pen.setWidth(2)
pen.setColor(QColor(255,10,10))
painter.setPen(pen)
brush=QBrush(QColor(200,200,10))
painter.setBrush(brush)
painter.drawPie(r,5040,1440)
if __name__=='__main__':
app=QApplication(sys.argv)
example=Example()
example.show()
app.exec_()
Is it possible to add a QWidget instead of calling drawItem?
For example, a suitably styled QPushButton could go in place of the rounded rectangles.
Alternatively, what is the best way to go about creating a display that contains both widgets and painted items?

Answer 1

I have written a rounded child widget example, using the QSS.
from PyQt4.QtGui import *
from PyQt4.QtCore import *
import sys
ROUNDED_STYLE_SHEET = """QPushButton {
background-color: red;
border-style: outset;
border-width: 2px;
border-radius: 10px;
border-color: beige;
font: bold 14px;
min-width: 10em;
padding: 6px;
}
"""
class MyWidget(QWidget):
def __init__(self, parent=None):
super(MyWidget, self).__init__(parent)
self.mChildWidget = QPushButton(self)
self.resize(600, 400)
self.mChildWidget.resize(120, 80)
self.mChildWidget.move(300, 200)
self.mChildWidget.setStyleSheet(ROUNDED_STYLE_SHEET)
if __name__ == '__main__':
app = QApplication(sys.argv)
w = MyWidget()
w.show()
app.exec_()