#include <QtGui>

static QGraphicsProxyWidget* wrapWidgetWithProxy( QWidget* widget )
{
QGraphicsProxyWidget* editProxy = new QGraphicsProxyWidget;
editProxy->setWidget( widget );
return editProxy;
}

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

QGraphicsView centerWidget;

QGraphicsScene* scene1 = new QGraphicsScene();
scene1->addSimpleText( "1" );
scene1->setBackgroundBrush( QBrush(QColor(255, 80, 80, 255)) );

QGraphicsScene* scene2 = new QGraphicsScene();
scene2->addSimpleText( "2" );
scene2->setBackgroundBrush( QBrush(QColor(70, 70, 70, 255)) );

/*comment away either setMinimumSize or setSizePolicy and it works*/

QGraphicsView* view1 = new QGraphicsView();
view1->setScene( scene1 );
view1->setMinimumSize( QSize(100,100) );
view1->setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum );

QGraphicsView* view2 = new QGraphicsView();
view2->setScene( scene2 );
view2->setMinimumSize( QSize(100,100) );
view2->setSizePolicy( QSizePolicy::Minimum, QSizePolicy::Minimum );


QTabBar* tabs = new QTabBar();
tabs->addTab ( "Input" );
tabs->addTab ( "Arrange" );
tabs->addTab ( "Launch" );
tabs->setCurrentIndex(0);
tabs->setDrawBase( false );
tabs->setTabsClosable(false);

QGraphicsGridLayout* layout = new QGraphicsGridLayout();
layout->addItem( wrapWidgetWithProxy( tabs ), 0, 0, 1, 1 );
layout->addItem( wrapWidgetWithProxy( view1 ), 1, 0, 1, 1 );
layout->addItem( wrapWidgetWithProxy( view2 ), 1, 1, 1, 1 );
layout->setSpacing( 1 );



QGraphicsWidget* enclosingWidget = new QGraphicsWidget();
QGraphicsScene* enclosingScene = new QGraphicsScene();

enclosingWidget->setLayout( layout );
enclosingScene->addItem( enclosingWidget );

centerWidget.setScene( enclosingScene );
centerWidget.resize(300,300);
centerWidget.show();

return app.exec();
}