no member function declared in class 'MainWindow' - c++

Question

I'm trying to make a fake FBI program for a prank, but it's not as easy as I expected it to be.
This is my code.
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
ui->trackConnButton->setEnabled(false);
}
void MainWindow::on_confirmButton_clicked() {
if (ui->usernameText == "name" && ui->passwordText == "password") {
ui->resullabel->setText("Password accepted.");
ui->trackConnButton->setEnabled(true);
} else {
ui->resullabel->setText("Password denied.");
}
}
MainWindow::~MainWindow()
{
delete ui;
}
I get this error:
D:\Qt-Projekte\test3\mainwindow.cpp:12: Fehler: no 'void MainWindow::on_confirmButton_clicked()' member function declared in class 'MainWindow'
void MainWindow::on_confirmButton_clicked() {
^
My question is now: how to fix it?
Thanks in advance.
my mainwindow.h:
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
private:
Ui::MainWindow *ui;
};
#endif // MAINWINDOW_H

Answer 1

All member functions of a class must contain a "declaration" and a "definition".
For example:
struct Foo {
// Declarations
void foo() const;
int bar(int x);
};
// Definitions
void Foo::foo() const {
std::cout << "foo" << std::endl;
}
int Foo::bar(int x) {
return x + 1;
}
(Note that if you define a function inline in a class, it counts as both definition and declaration):
struct Foo {
// Declaration AND definition
void foo() const {
std::cout << "foo inline" << std::endl;
}
};
So in your case, you must declare the on_confirmButton_clicked function inside the definition of class MainWindow.