#ifndef PROGRESSBAR_H#define PROGRESSBAR_H#include <QProgressBar>class QString;class ProgressBar: public QProgressBar{    Q_OBJECTpublic:    ProgressBar(QWidget *parent = 0):QProgressBar(parent){}    QString strText;public slots:    void stepOne();};#endif // PROGRESSBAR_H

#include "progressbar.h"#include <QString>void ProgressBar::stepOne(){    if(this->value()+1 <= this->maximum())    {        this->setValue(this->value()+1);        strText = "QProgressBar Test : "+this->text();        this->setWindowTitle(strText);    }    else    {        this->setValue(this->minimum());    }}

#include <QApplication>#include <QTimer>#include "progressbar.h"int main(int argc, char**argv){    QApplication app(argc, argv);    //progressBar    ProgressBar *progressBar = new ProgressBar;    progressBar->setWindowTitle("QProgressBar Test");    progressBar->resize(400,40);    progressBar->setMaximum(100);    progressBar->setMinimum(0);    progressBar->setValue(0);    //define a timer    QTimer *timer = new QTimer;    timer->start(500);    QObject::connect(timer, SIGNAL(timeout()), progressBar, SLOT(stepOne()));    progressBar->show();    return app.exec();}