RadioBox Signal Confusion

Question

I tried to create multi QRadioButton in different QGroupBox. After that I would like to print() which QRadioButton pressed in screen.

When I push first button in QGroupBox there is no problem. However, In second try first and second button printted to screen. If you try my code, you will see cleary what I meant

After code work well, I will connect different function for each QRadioButton. This is why output signal is importnat for me

Here is my code;

from PyQt5.QtWidgets import *


import sys


class ButtonWidget(QWidget):

    def __init__(self):
        super(ButtonWidget, self).__init__()

        groups = {"Functions": ("Sinus", "Cosines"),
                  "Colors": ("Red", "Green"),
                  "Lines": ("Solid", "Dashed")
                  }

        # Main Group
        main_group = QGroupBox("Operations")
        main_group_layout = QHBoxLayout()

        # loop on group names
        for group, buttons in groups.items():
            group_box = QGroupBox(group)
            group_layout = QVBoxLayout()
            for button_text in buttons:
                button = QRadioButton(button_text)
                button.setObjectName("radiobutton_%s" % button_text)

                button.toggled.connect(self.radio_func)

                group_layout.addWidget(button)

            group_box.setLayout(group_layout)
            main_group_layout.addWidget(group_box)

        main_group.setLayout(main_group_layout)

        # Widget
        main_widget = QWidget()
        main_widget_layout = QVBoxLayout()
        main_widget.setLayout(main_widget_layout)
        main_widget_layout.addWidget(main_group)
        # Layout Set
        self.setLayout(main_widget_layout)

        self.show()

    def radio_func(self):
        radio_btn = self.sender()
        print(f"{radio_btn.text()}\n-------------------")


if __name__ == "__main__":
    app = QApplication(sys.argv)
    ui = ButtonWidget()
    sys.exit(app.exec_())

When I use QPushButton instead of QRadioButton, there isn't such problem, but I need to use QRadioButton — Gokberk, May 25 '20 at 19:42

score 2 · Accepted Answer · answered May 25 '20 at 19:46

The toggled signal notifies of the change of state in the QRadioButton, at the beginning all are unchecked so when pressing one button one of them changes status from unchecked to checked, when you press another button then the button that is checked changes to unchecked, and the pressed change from unchecked to checked, that is, there are 2 buttons that change state so 2 signals will be emitted.

One possible solution is to use the state transmitted by the signal:

def radio_func(self, on):
    if on:
        radio_btn = self.sender()
        print(f"{radio_btn.text()}\n-------------------")

Another solution is to use the clicked signal:

button.clicked.connect(self.radio_func)

Thank you for your time. How can I set default check "let's say sinus" ? For my code — Gokberk, May 25 '20 at 19:49
@Gokberk use `if button_text == "Foo text": button.setChecked(True)` — eyllanesc, May 25 '20 at 19:51

RadioBox Signal Confusion

1 Answers1