error with python qt message box

Question

The messagebox keeps 'flashing' :s. It doesn't crash, but it just keeps on opening and re-opening. How could I fix this problem?

self.retranslateUi(Login)
    QtCore.QObject.connect(self.ExitButton, QtCore.SIGNAL(_fromUtf8("clicked()")), Login.close)
    QtCore.QObject.connect(self.LoginButton, QtCore.SIGNAL("clicked()"),self.get_value_from_user)
    QtCore.QMetaObject.connectSlotsByName(Login)
    Login.setTabOrder(self.LoginButton, self.UsernameEdit)
    Login.setTabOrder(self.UsernameEdit, self.PasswordEdit)
    Login.setTabOrder(self.PasswordEdit, self.ExitButton)

def get_value_from_user(self):
    Correct_details = False
    while Correct_details==False:
        inputusername=self.UsernameEdit.text()
        inputpassword=self.PasswordEdit.text()
        cur.execute("SELECT password FROM tblStaff WHERE username='"+inputusername+"'")
        password=str(cur.fetchone())
        password=password[2:-3]
        cur.execute("SELECT firstname FROM tblStaff WHERE username='"+inputusername+"'")
        FirstName=str(cur.fetchone())
        FirstName=FirstName[2:-3]
        cur.execute("SELECT surname FROM tblStaff WHERE username='"+inputusername+"'")
        Surname=str(cur.fetchone())
        Surname=Surname[2:-3]
        if str(password) == str(inputpassword):
            self.msgBox1 = QMessageBox(QMessageBox.Information,'Successful', "Succesfully Logged in")
            self.msgBox1.show()
            Correct_details = True
        else:
            self.msgBox2 = QMessageBox(QMessageBox.Information, 'Warning', "The Username or Password you have entered is incorrect")
            self.msgBox2.show()

Can you please show when/where get_value_from_user is called? — Amaury Medeiros, Apr 21 '14 at 17:39

score 0 · Accepted Answer · edited Jan 04 '17 at 08:46

0

Your program logic is wrong. Inside the get_value_from_user() method, you have the line while Correct_details==False:. This is the line that is causing the problem. Once the user has entered their incorrect login details, they don't get the option to enter them again, you just repeatedly read out the same login details from self.UsernameEdit and self.PasswordEdit and of course the continue to not be correct, and so the loop runs forever and each iteration of the loop, you pop up the message box saying they are incorrect.

The loop mentioned above needs to be somewhere else in your code (possibly in the method that calls get_value_from_user), that allows the user to re-enter their username and password. The get_value_from_user() method should probably return the variable Correct_Details so that the calling method can decide whether to present the user with the login form again, or proceed.

edited Jan 04 '17 at 08:46

Termininja

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answered Apr 22 '14 at 02:16

three_pineapples

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thanks alot man, yeah, i just cleared the lineedit so they can re-enter the username and password, and used a break if they entered it wrong:) btw, do you know how to connect to different widgets? i have been reading a lot around the subject, but find it hard to understand any of them. i have two different widgets in two different .py files, i want to open the other one if the login is successful in this one :S – Thaz Apr 22 '14 at 14:56
@Thaz probably best to post that as another question on SO – three_pineapples Apr 22 '14 at 21:44

error with python qt message box

1 Answers1