To send two arguments to a function with the click of a button

Question

I have used QT Designer to have two QLineEdit's to take input from the user. After the user enters the values , when the Enter button is clicked I need the buttons to pass the values to the disk_angles function.

How to pass two strings to a function via signals with the press of a button? Here is my code

class Maindialog(QMainWindow,diskgui.Ui_MainWindow):

    pass_arguments = SIGNAL((str,),(str,))

    def __init__(self,parent = None):

        super(Maindialog,self).__init__(parent)
        self.setupUi(self)

        self.connect(self.Home,SIGNAL("clicked()"),self.home_commands)
        self.connect(self.AutoFocus,SIGNAL("clicked()"),self.auto_focus)

        self.Enter.clicked.connect(self.entervalues)
        self.connect(self,SIGNAL("pass arguments"),self.Criterion_disk_angles)

    def entervalues(self):
        if self.RotationEdit.text() != "" and self.TiltEdit.text() != "":
        self.RotationEdit = str(self.RotationEdit.text())
        self.TiltEdit = str(self.TiltEdit.text())
        self.pass_arguments.emit(self.RotationEdit,self.TiltEdit)

    def disk_angles(self,rotation_angle, tilt_angle):

I have tried to pass tuples as input to the signal pass_arguments = SIGNAL((str,),(str,)) but I get the error

         pass_arguments = SIGNAL((str,),(str,))
         TypeError: SIGNAL() takes exactly one argument (2 given)

Did you read the error? `SIGNAL` take 1 argument, but you provided 2... — Andrew Li, Jan 19 '17 at 17:23
@Andrew Li Yes but I read you can pass two arguments in a signal if you pass it as a tuple. But I mite have understood it wrong — Raghavendra MG, Jan 19 '17 at 17:24
and self.pass_arguments.emit((self.RotationEdit,self.TiltEdit)) — eyllanesc, Jan 19 '17 at 17:25
@RaghavendraMG `(str,),(str,)` isn't just one tuple, it's *two* tuples... — Andrew Li, Jan 19 '17 at 17:26
@eyllanesc Now I am getting the error TypeError: 'SIGNAL' called with wrong argument types: SIGNAL(type, type) Supported signatures: SIGNAL(unicode) — Raghavendra MG, Jan 19 '17 at 17:28
@RaghavendraMG Pass the correct type of argument... if you want tuples for multiple arguments learn about unpacking. — Andrew Li, Jan 19 '17 at 17:35

eyllanesc · Accepted Answer · 2017-01-19T17:43:40.360

In PyQt5 it is recommended to use the new style, In addition you are sending 2 tuples of place of one, here I show an example of a correct implementation.

import sys

from PyQt5.QtCore import QObject, pyqtSignal
from PyQt5.QtWidgets import QApplication, QPushButton


class Widget(QObject):
    sig = pyqtSignal((str, str))

    def __init__(self, parent=None):
        super(Widget, self).__init__(parent=parent)
        self.sig.connect(self.printer)

    def click(self):
        self.sig.emit("hello", "bye")

    def printer(self, text1, text2):
        print(text1, text2)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    w = QPushButton()
    w1 = Widget()
    w.clicked.connect(w1.click)
    w.show()
    sys.exit(app.exec_())

To send two arguments to a function with the click of a button

1 Answers1