#include <QtOpenGL/qgl.h>
#ifndef QGL_H
class QGLWidget: public QWidget{
   /* Some contents are skipped to improve readability */
   public: explicit QGLWidget(class QWidget* parent = 0, class QGLWidget const * shareWidget = 0, Qt::WindowFlags f = 0);
   /* ... */
};
#endif // QGL_H