#include <QtWidgets>
#include <QtGui>

class TWindow : public QMainWindow
{
public:
	TWindow() {}
	void	mousePressEvent(QMouseEvent*)
	{
		QPoint pos = QCursor::pos();
		QWidget* w = QApplication::widgetAt(pos);
		Q_ASSERT(w == this);
	}
};

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

	TWindow* w1 = new TWindow;
	w1->show();
	TWindow* w2 = new TWindow;
	w2->show();

	return app.exec();
}