C++ : Faire passer des infos entre un QWid...

// Dans le programme principal
void MainWindow::btnDialog_clicked()
{
  Dlg dlg (this);
  if (dlg.exec())
    qDebug() << dlg.getSpinBox() << " - " << dlg.getLineEdit();
}

// La classe à déclarer
// Dlg.h
#include <QtGui>
class Dlg : public QDialog
{
  Q_OBJECT

  public:
    DlgDivers(QWidget* parent=0);
    QString getLineEdit(void) { return (lineEdit->text()); }
    int getSpinBox(void) { return (spinBox->value()); }
  private:
    QLineEdit* lineEdit;
    QSpinBox* spinBox;
    QPushButton* btnAnnuler;
    QPushButton* btnOK;
};

// Dlg.cpp
#include "dlgDivers.h"
DlgDivers::DlgDivers(QWidget* parent) : QDialog(parent)
{
  setWindowTitle (trUtf8 ("Essai >>> Dialog <<<"));
  lineEdit = new QLineEdit;
  spinBox = new QSpinBox;
  btnAnnuler = new QPushButton("Annuler");
  btnOK = new QPushButton("OK");
  connect (btnAnnuler, SIGNAL(clicked()), this, SLOT(reject()));
  connect (btnOK     , SIGNAL(clicked()), this, SLOT(accept()));

  QVBoxLayout* vLayout = new QVBoxLayout;
  vLayout->addWidget(lineEdit);
  vLayout->addWidget(spinBox);
  vLayout->addWidget(btnAnnuler);
  vLayout->addWidget(btnOK);
  setLayout(vLayout);
}