QPainter painter(this); painter.setBrush(Qt::red); painter.setPen(Qt::red); painter.drawRoundRect(10, 10, 80, 80, 20, 20);
QPainter painter(this); painter.setPen(Qt::green); painter.drawRoundRect(100, 10, 80, 60, 30, 30);
QPainter painter(this); painter.setRenderHint(QPainter::Antialiasing); painter.setPen(Qt::blue); painter.drawRoundRect(200, 10, 60, 80, 10, 10);In this example, an antialiasing render hint is set, a blue pen is set, and then a rounded rectangle is drawn with coordinates (200, 10) and dimensions (60, 80), and corner radii of 10. The package library for Qt is "Qt5Core" and "Qt5Widgets".