[FIXED] Multiple QGraphicsViews and QGraphicsScenes in a MainWindow

Issue

I am looking to develop a Qt application whose main/parent widget is capable of 'holding' one or more "special" widgets. Each special widget displays a separate QGraphicsView and QGraphicsScene.

As far as I can see there can only be one central widget to which a graphics view can be set i.e. QMainWindow::setCentralWidget( QGraphicsView ), whereas I would like to have multiple graphics views.

Here is my failed quick and dirty attempt (in PySide)

#!/usr/bin/python

from PySide import QtGui
import sys

class MyApp(QtGui.QMainWindow):
    def __init__(self):
        QtGui.QMainWindow.__init__(self)
        layout = QtGui.QHBoxLayout()

        self.scene1 = QtGui.QGraphicsScene(self)
        self.scene1.addRect(5,5,200,200)
        self.view1 = QtGui.QGraphicsView(self.scene1, self)

        self.scene2 = QtGui.QGraphicsScene(self)
        self.scene2.addLine(500,500,300,300)
        self.view2 = QtGui.QGraphicsView(self.scene1, self)

        layout.addWidget(self.view1)
        layout.addWidget(self.view2)

        self.setLayout(layout)
        self.show()

if __name__=="__main__":
    app=QtGui.QApplication(sys.argv)
    myapp = MyApp()
    sys.exit(app.exec_())

Solution

QMainWindow has a default layout, you do not have to set it. In Qt a QWidget can be used as a container, so we create a widget that will be the container of the QGraphicsViews and also the centralwidget:

class MyApp(QtGui.QMainWindow):
    def __init__(self, parent=None):
        super(MyApp, self).__init__(parent)

        self.scene1 = QtGui.QGraphicsScene(self)
        self.scene1.addRect(5,5,200,200)
        self.view1 = QtGui.QGraphicsView(self.scene1)

        self.scene2 = QtGui.QGraphicsScene(self)
        self.scene2.addLine(500,500,300,300)
        self.view2 = QtGui.QGraphicsView(self.scene2)

        central_widget = QtGui.QWidget()
        layout = QtGui.QHBoxLayout(central_widget)
        layout.addWidget(self.view1)
        layout.addWidget(self.view2)
        self.setCentralWidget(central_widget)
        self.show()

Answered By - eyllanesc