Qt not getting text from lineedit - c++

Question

QString username = ui->lineEdit->text();
QString password = ui->lineEdit_2->text();
QMessageBox Failed;
Failed.setWindowFlags(Qt::FramelessWindowHint);
if(username == "Jon" && password == "12345")
{
Failed.setText("Login failed. Try again.");
Failed.exec();
} else {
Failed.setText(password);
Failed.exec();
}
Using qt.
Sorry if this has been asked before I'm quite new and couldn't find a answer.
I don't understand what I'm doing wrong. I set username and password to the text inside the line edits on the ui. But everytime i click this button function the output of the dialog text is always blank. How can i get it so the the text is read?

Answer 1

alright, I ran some tests and this is what i found got:
if you set up some sort of signal slot connection that calls a function containg those if/else statmentsthe program will work. this is the following program i made:
dialog.h:
#ifndef DIALOG_H
#define DIALOG_H
#include "ui_dialog.h"
#include <QDialog>
class DialogClass : public QDialog, public Ui::Dialog
{
Q_OBJECT
public:
DialogClass(QWidget *parent = 0);
public slots:
void check();
};
#endif // DIALOG_H
Dialog.cpp:
#include "dialog.h"
#include <QMessageBox>
DialogClass::DialogClass(QWidget *parent) : QDialog(parent)
{
setupUi(this);
connect(pushButton, SIGNAL(clicked()), this, SLOT(check()));
}
void DialogClass::check()
{
QString username = lineEdit->text();
QString password = lineEdit_2->text();
QMessageBox Failed;
Failed.setWindowFlags(Qt::FramelessWindowHint);
if(username == "Jon" && password == "12345")
{
Failed.setText("Login failed. Try again.");
Failed.exec();
} else {
Failed.setText(password);
Failed.exec();
}
}
and main.cpp
#include <QApplication>
#include <QMessageBox>
#include "dialog.h"
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
DialogClass w;
w.show();
return a.exec();
}
bassically, all that I do is make a dialog class a lot like your main function, only that mine has a button dialog.ui has a button. After that, I use the button to establish a signal slot connection that ensures that when this button is clicked, it will call the check() function (which is basically your if/else algorithm make into a slot), which checks to see if the username is "Jon", and password is "12345".
Why your original implementation didn't work?
I am sorry, but i am not sure.
However, this approach should work. I will add to the answer if I ever do figure out why the if statements weren't picking up. However, this approach should get your application working.
happy coding!