title: pyQt5: Cannot connect QSpinBox::valueChanged(int)
body: <p>I am new to Python and Qt. Currently, I am trying to build the UI for a larger application, but I am running into problems regarding signals and slots.</p>
  
  <p>Here is my code:</p>
  
  <pre><code>from PyQt5 import QtCore, QtGui, QtWidgets
  from PyQt5.QtCore import QObject, pyqtSlot
  import sys
  
  
  class Ui_configDialog(QtWidgets.QDialog):
      def __init__(self):
          super(Ui_configDialog, self).__init__()
  
          self.setupUi()
  
      def setupUi(self):
          self.setObjectName("configDialog")
          self.setWindowModality(QtCore.Qt.WindowModal)
          self.resize(425, 380)
  
          row1 = DataRow(self)
  
          self.show()
  
  
  class DataRow:
      def __init__(self, dialog):
          rect = QtCore.QRect(10, 40, 91, 30)
  
          self.text_fRep = QtWidgets.QSpinBox(dialog)
          self.text_fRep.setGeometry(rect.translated(100, 0))
          self.connect_signal()
  
      @pyqtSlot(int)
      def fRep_changed(self, value):
          print(value)
  
      def connect_signal(self):
          self.text_fRep.valueChanged.connect(self.fRep_changed)
  
  
  if __name__ == "__main__":
      app = QtWidgets.QApplication(sys.argv)
      dialog = Ui_configDialog()
      sys.exit(app.exec_())
  </code></pre>
  
  <p>What I am trying to achieve is, that the slot fRep_changed is called whenever the value of the QSpinBox object is changed. But with this code I receive a compile error:</p>
  
  <pre><code>QObject::connect: Cannot connect QSpinBox::valueChanged(int) to (null)::fRep_changed(int)
  TypeError: connect() failed between valueChanged(int) and fRep_changed()
  </code></pre>
  
  <p>I cannot see, why I shouldn't be able to connect the signal to the slot.</p>
  
  <p>I also removed the @pyqtSlot(int). The application starts, but nothing happens when the value is changed.</p>
  
  <p>Thank you for your help in advance!</p>