#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
    class MainWindow;
}

class MainWindow : public QMainWindow {
    Q_OBJECT
public:
    MainWindow(QWidget *parent = 0);
    ~MainWindow();

public slots:
    void buttonClickHandler();

protected:
    void changeEvent(QEvent *e);

private:
    Ui::MainWindow *ui; 
    {
    private:  // member functions
             void MainWindow::initMyWordList()
    private: // member variables
            static int  _clickCounter;
            QStringList _wordList;
    };
private slots:

private slots:
    void on_Button_clicked();
};


#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QLabel>
int MainWindow::_clickCounter = 0;
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::changeEvent(QEvent *e)
{
    QMainWindow::changeEvent(e);
    switch (e->type()) {
    case QEvent::LanguageChange:
        ui->retranslateUi(this);
        break;
    default:
        break;
    }
}

void MainWindow::buttonClickHandler()
{
}

void MainWindow::on_Button_clicked()
{
....
error = initMyWordList();
if ( error )
   do whatever you feel like
....
}

//init my word file
void MainWindow::initMyWordList()
{
        QFile * wordFile = new QFile("/home/user/wordlist");
        wordFile->open(QIODevice::ReadOnly);

        QTextStream stream(wordFile);

        // create the map of channel and date until which data is available
        while ( !stream.atEnd() )
        {
                QString word = stream.readLine();
                _wordList << word;
        }

        wordFile->close();
}

void MainWindow::on_Button_clicked()
{
       ui->label->setText(QString("the word of the day is %1").arg(_wordList[_clickCounter++]) );
}