grouping radio buttons in PyQt

Question

import sys
from PyQt4 import QtCore, QtGui

class Class1(QtGui.QMainWindow):
    def __init__(self):
        super(Class1, self).__init__()
        self.func()

             


        

Answer 1

A QMainWindow provides a layout already, you can't simply replace that with your own. Either inherit from a plain QWidget, or create a new widget and add the layout and buttons to that.

Your naming is confusing too, QButtonGroup isn't a layout. It doesn't actually provide any visible UI. If you need a UI element that groups buttons, you should look at QGroupBox instead.

Here's a simple variation on what you have above:

def func(self):
    layout=QtGui.QHBoxLayout()  # layout for the central widget
    widget=QtGui.QWidget(self)  # central widget
    widget.setLayout(layout)

    number_group=QtGui.QButtonGroup(widget) # Number group
    r0=QtGui.QRadioButton("0")
    number_group.addButton(r0)
    r1=QtGui.QRadioButton("1")
    number_group.addButton(r1)
    layout.addWidget(r0)
    layout.addWidget(r1)

    letter_group=QtGui.QButtonGroup(widget) # Letter group
    ra=QtGui.QRadioButton("a")
    letter_group.addButton(ra)
    rb=QtGui.QRadioButton("b")
    letter_group.addButton(rb)
    layout.addWidget(ra)
    layout.addWidget(rb)

    # assign the widget to the main window
    self.setCentralWidget(widget)
    self.show()

Answer 2

Grouping of radio buttons can be done by all containers. You don't necessarily need QGroupBox, you can use QFrame instead or a QTabWidget. Your choice. Here's a sample code.

    self.centralwidget = QtWidgets.QWidget(MainWindow)
    self.layoutWidget1 = QtWidgets.QWidget(self.centralwidget)
    self.frame_1       = QtWidgets.QFrame(self.layoutWidget1)
    self.radio_btn_a   = QtWidgets.QRadioButton(self.frame_1)
    self.radio_btn_a.setGeometry(QtCore.QRect(160, 80, 40, 17))
    self.radio_btn_a.setObjectName("radio_btn_a")
    MainWindow.setCentralWidget(self.centralwidget)