main.cpp Example File

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 #include <QtGui>

 // ![0]
 #include <QtGui/QX11Info>
 #include <X11/Xlib.h>
 #include <X11/Xatom.h>
 // ![0]

 class ZoomWidget : public QWidget
 {
     Q_OBJECT

 public:
     ZoomWidget()
     {
         QVBoxLayout *layout = new QVBoxLayout(this);

         progressBar = new QProgressBar;
         progressBar->setValue(50);

         layout->addWidget(new QLabel("<p align=\"center\">Please press the zoom keys</p>"));
         layout->addWidget(progressBar);

         grabZoomKeys(true);
     }

 // ![1]
     void grabZoomKeys(bool grab)
     {
         if (!winId()) {
             qWarning("Can't grab keys unless we have a window id");
             return;
         }

         unsigned long val = (grab) ? 1 : 0;
         Atom atom = XInternAtom(QX11Info::display(), "_HILDON_ZOOM_KEY_ATOM", False);
         if (!atom) {
             qWarning("Unable to obtain _HILDON_ZOOM_KEY_ATOM. This example will only work "
                      "on a Maemo 5 device!");
             return;
         }

         XChangeProperty (QX11Info::display(),
                 winId(),
                 atom,
                 XA_INTEGER,
                 32,
                 PropModeReplace,
                 reinterpret_cast<unsigned char *>(&val),
                 1);
     }
 // ![1]

 protected:
 // ![2]
     void keyPressEvent(QKeyEvent* event)
     {
         switch (event->key()) {
         case Qt::Key_F7:
             progressBar->setValue(progressBar->value() + 1);
             event->accept();
             break;

         case Qt::Key_F8:
             progressBar->setValue(progressBar->value() - 1);
             event->accept();
             break;
         }
         QWidget::keyPressEvent(event);
     }
 // ![2]

 private:
     QProgressBar *progressBar;
 };

 int main(int argc, char *argv[])
 {
     QApplication app(argc, argv);

     ZoomWidget w;
     w.show();

     return app.exec();
 }

 #include "main.moc"