connect(this, SIGNAL(sceneRectChanged(const QRectF &)), this, SLOT(rectChanged(const QRectF &)));
connect(model, SIGNAL(rowsInserted(const QModelIndex &, int, int)), this, SLOT(rowsInserted(const QModelIndex &, int, int)));
connect(this, SIGNAL(sceneRectChanged(const QRectF &)), this, SLOT(rectChanged(const QRectF &)));
connect(model, SIGNAL(rowsInserted(const QModelIndex &, int, int)), this, SLOT(rowsInserted(const QModelIndex &, int, int)));