I finally found a method that works, that I want so share:

void myWidget::moveEvent(QMoveEvent *event) { Qt::MouseButtons mouse = qApp->mouseButtons(); if(mouse != Qt::LeftButton) { std::cout << "move end" << std::endl; } }

If you check the mouse status in the moveEvent(), on the last move event the mouse will not be pressed anymore, which is kind of like a mouse release event. At least it works for me at the moment.