Movable QLabel using the mouse. Stackoverflow question: https://stackoverflow.com/questions/60463917/how-to-make-qlabel-of-qt-draggable

movablelabel.cpp

#include <QLabel>
#include <QMouseEvent>
#include <QMainWindow>
#include <QApplication>

class MovableLabel : public QLabel
{
public:
    MovableLabel(QWidget* parent = nullptr): QLabel(parent)
    {
        setAlignment(Qt::AlignCenter);
        setFrameStyle(QFrame::StyledPanel | QFrame::Raised);
        setLineWidth(2);
    }
    void mousePressEvent(QMouseEvent *event) override
    {
        if (event->button() == Qt::LeftButton) {
            QApplication::setOverrideCursor(QCursor(Qt::ClosedHandCursor));
            m_pos = event->pos();
        }
    }
    void mouseMoveEvent(QMouseEvent *event) override
    {
        if (!m_pos.isNull()) {
            move(mapToParent(event->pos() - m_pos));
        }
    }
    void mouseReleaseEvent(QMouseEvent *event) override
    {
        if (event->button() == Qt::LeftButton) {
            m_pos = QPoint();
            QApplication::restoreOverrideCursor();
        }
    }
private:
    QPoint m_pos;
};

class MainWindow : public QMainWindow
{
public:
    MainWindow(QWidget *parent = nullptr) : QMainWindow(parent)
    {
        resize(600,400);
        auto label = new MovableLabel(this);
        label->setText("Move Me!");
        label->move(50, 50);
    }
};

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();
    return a.exec();
}