Custom signal not working in PySide

Question

I am new to PySide and I'm trying to emit a signal and receive it from another class.

I have used emit on the object of the MySignal class and signal is being emitted from the MyRadioButton class. Both emit and connect are returning True but as I want, the update method is not being called

This is the basic structure of files and code.

# MySignals.py
from PySide.QtCore import QObject, Signal

class MyCheckedSignal(QObject):
    signal = Signal(str)


# MyRadioButton.py
class MyRadioButton(QWidget, QObject):
    def __init__(self, value=None, label=None):
        QWidget.__init__(self)
        self.__value = value
        self.__checked = False
        self.checkSignal = MySignals.MyCheckedSignal()

    def toggleCheck(self):
        if self.__checked == False:
                self.__checked = True
                self.checkSignal.emit(SIGNAL(self.__value))
        else:
                self.__checked = False


# MyRadioGroup.py
class MyRadioGroup(QObject):
    def __init__(self, radioes=None):
        QObject.__init__(self)
        for radio in radioes:
            # radio is of type MyRadio
            # self.connect(radio, SIGNAL("checked()"), self.update)
            radio.checkSignal.signal.connect(self.update)
            # self.connect(self.update)

    def update(self, value):
        print("Checked", value)

Answer 1

Foreword: Your choice of base class seems strange: your MyRadioButton should probably inherit from QRadioButton and your MyRadioGroup would benefit inheriting from QGroupBox , which is a proper widget, and will therefore integrate well with the rest of the application. Look at the description inside for a concrete example with layouts.

To your specific question, and without using the existing QRadioButton , you don't need to create your special class for the signal. Simply declare your MyRadioButton as follow:

class MyRadioButton(QPushButton):
    checkSignal = QtCore.Signal(str)

    def __init__(self, value=None, label=None):
        QPushButton.__init__(self)
        self.__value = value
        self.__checked = False
        self.setCheckable(True)  # This will 'hold' the button once clicked
        self.clicked.connect(self.toggleCheck)  # Signal emitted on click

    def toggleCheck(self):
        if self.__checked == False:
                self.__checked = True
                self.checkSignal.emit(self.__value)
        else:
                self.__checked = False

Notice that for your toggleCheck method to be activated, you have to connect the signal from QAbstractButton : clicked , to the method. Your RadioGroup then becomes simply (inheriting from QWidget is a good idea if you want to display it in some way):

class MyRadioGroup(QWidget):
    def __init__(self, radioes=None):
        QWidget.__init__(self)
        self.radioes = radioes  # good idea to store a reference to it
        for radio in radioes:
            radio.checkSignal.connect(self.update)

    def update(self, value):
        print("Checked", value)

I will paste below the entire file for you to test. On my setup ( Python 2.7.8 , PySide 1.2.2 ), this work fine.

As an aside: I am confused by your line self.checkSignal.emit(SIGNAL(self.__value)) . What is this SIGNAL ? Maybe I missed something from your question.

---

full example file:

import sys
from PySide import QtGui
from PySide import QtCore

class MyRadioButton(QtGui.QPushButton):
    checkSignal = QtCore.Signal(str)

    def __init__(self, text, value=None, label=None):
        QtGui.QPushButton.__init__(self, text)
        self.__value = value
        self.__checked = False
        self.setCheckable(True)
        self.clicked.connect(self.toggleCheck)

    def toggleCheck(self):
        if self.__checked == False:
                self.__checked = True
                self.checkSignal.emit(self.__value)
        else:
                self.__checked = False


class MyRadioGroup(QtGui.QWidget):
    def __init__(self, radios=None):
        QtGui.QWidget.__init__(self)
        self.radios = radios
        for radio in self.radios:
            radio.checkSignal.connect(self.update)

    def update(self, value):
        print("Checked", value)

app = QtGui.QApplication(sys.argv)

radio1 = MyRadioButton('Hello toto', value='toto')
radio2 = MyRadioButton('Hello titi', value='titi')
group = MyRadioGroup(radios=[radio1, radio2])

vbox = QtGui.QVBoxLayout()
vbox.addWidget(radio1)
vbox.addWidget(radio2)
vbox.addStretch(1)
group.setLayout(vbox)
group.resize(250, 150)
group.setWindowTitle('Signals')
group.show()

sys.exit(app.exec_())