AttributeError: 'Ui_Form' object has no attribute 'printHam_btn'

Question

I'm started learning QtDesigner (Python) with Qt 4.8.6 and I follow this tutorial:

https://www.youtube.com/watch?v=GLqrzLIIW2E

but it showing me sometimes error in title sometimes AttributeError: 'Ui_Form' object has no attribute 'printHam_btn'. Can someone please tell me what i have to do or fix my code.

Thanks!

I know that this problem is already post in this forum but I can't find out what I have to do in my case.

CODE:

from PyQt4 import QtCore, QtGui
import sys

try:
    _fromUtf8 = QtCore.QString.fromUtf8
except AttributeError:
    def _fromUtf8(s):
        return s

try:
    _encoding = QtGui.QApplication.UnicodeUTF8
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig, _encoding)
except AttributeError:
    def _translate(context, text, disambig):
        return QtGui.QApplication.translate(context, text, disambig)

class Ui_Form(QtGui.QWidget):
    def __init__(self):
        QtGui.QWidget.__init__(self)
        self.setupUi(self)

    def setupUi(self, Form):
        Form.setObjectName(_fromUtf8("Form"))
        Form.resize(400, 300)
        self.verticalLayout_2 = QtGui.QVBoxLayout(Form)
        self.verticalLayout_2.setObjectName(_fromUtf8("verticalLayout_2"))
        self.verticalLayout = QtGui.QVBoxLayout()
        self.verticalLayout.setObjectName(_fromUtf8("verticalLayout"))
        self.print_ham = QtGui.QPushButton(Form)
        self.print_ham.setObjectName(_fromUtf8("print_ham"))
        self.verticalLayout.addWidget(self.print_ham)
        self.verticalLayout_2.addLayout(self.verticalLayout)

        self.retranslateUi(Form)
        QtCore.QMetaObject.connectSlotsByName(Form)

    def retranslateUi(self, Form):
        Form.setWindowTitle(_translate("Form", "Super ham", None))
        self.print_ham.setText(_translate("Form", "print ham", None))
        self.printHam_btn.clicked.connect(self.printHam)

    def printHam(self):
        print('Ham!')

if __name__ == "__main__":
    app = QtGui.QApplication(sys.argv)
    main_window = Ui_Form()
    main_window.show()
    sys.exit(app.exec_())

Answer 1

The issue is here:

self.printHam_btn.clicked.connect(self.printHam)

You call your QPushButton instance differently, so you would need to change this line to:

self.print_ham.clicked.connect(self.printHam)