I am having trouble with the dragging of items inside a QListWidget, the items which are selected are stuck with the mouse cursor even after the mouse button is released. I want to reorder the items inside the QListWidget by dragging them though mouse while the mouse left button is pressed.
I have promoted my ui->listwidget to a custom listwidget to accept drag and drops.

Qt Code: 
  1. #ifndef PROJECTLISTWIDGET_H
  2. #define PROJECTLISTWIDGET_H
  3.  
  4. class ProjectListWidget : public QListWidget
  5. {
  6.     Q_OBJECT
  7. public:
  8.     ProjectListWidget(QWidget *parent = 0);
  9.  
  10. signals:
  11.     void itemDrag();
  12.  
  13. protected:
  14.     void mousePressEvent(QMouseEvent *event);
  15.     void mouseMoveEvent(QMouseEvent *event);
  16.     void dragEnterEvent(QDragEnterEvent *event);
  17.     void dragMoveEvent(QDragMoveEvent *event);
  18.     void dropEvent(QDropEvent *event);
  19.     void performDrag();
  20.     QPoint startPos;
  21. };
  22.  
  23.  
  24. #endif // PROJECTLISTWIDGET_H
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Qt Code: 
  1. #include "projectlistwidget.h"
  2.  
  3. using namespace std;
  4.  
  5. ProjectListWidget::ProjectListWidget(QWidget *parent)
  6.     : QListWidget(parent)
  7. {
  8.     setAcceptDrops(true);
  9.     setDragEnabled(true);
  10. }
  11.  
  12. void ProjectListWidget::mousePressEvent(QMouseEvent *event)
  13. {
  14.     if (event->button() == Qt::LeftButton)
  15.     {
  16.         startPos = event->pos();
  17.     }
  18.     QListWidget::mousePressEvent(event);
  19.  
  20. }
  21.  
  22. void ProjectListWidget::mouseMoveEvent(QMouseEvent *event)
  23. {
  24.     if (event->buttons() & Qt::LeftButton)
  25.     {
  26.         int distance = (event->pos() - startPos).manhattanLength();
  27.         if (distance >= QApplication::startDragDistance())
  28.         {
  29.             performDrag();
  30.         }
  31.     }
  32.     QListWidget::mouseMoveEvent(event);
  33. }
  34.  
  35. void ProjectListWidget::performDrag()
  36. {
  37.     QListWidgetItem *item = currentItem();
  38.     if (item) {
  39.         QMimeData *mimeData = new QMimeData;
  40.         mimeData->setText(item->text());
  41.         QDrag *drag = new QDrag(this);
  42.         drag->setMimeData(mimeData);
  43.         emit itemDrag();
  44.         if (drag->exec(Qt::MoveAction) == Qt::CopyAction)
  45.             delete item;
  46.     }
  47. }
  48.  
  49. void ProjectListWidget::dragEnterEvent(QDragEnterEvent *event)
  50. {
  51.     if (event->mimeData()->hasUrls())
  52.     {
  53.         event->acceptProposedAction();
  54.     } else
  55.     {
  56.         QListWidget::dragEnterEvent(event);
  57.     }
  58. }
  59.  
  60. void ProjectListWidget::dragMoveEvent(QDragMoveEvent *event)
  61. {
  62.     if (event->mimeData()->hasUrls() & Qt::LeftButton)
  63.     {
  64.         event->acceptProposedAction();
  65.     } else
  66.     {
  67.         QListWidget::dragMoveEvent(event);
  68.     }
  69. }
  70.  
  71. void ProjectListWidget::dropEvent(QDropEvent *event)
  72. {
  73.     if (event->mimeData()->hasUrls())
  74.     {
  75.         QList<QUrl> urls = event->mimeData()->urls();
  76.         if (!urls.isEmpty())
  77.         {
  78.             QUrl url;
  79.             foreach (url,urls)
  80.             {
  81.                 new QListWidgetItem(url.toLocalFile(),this);
  82.                 emit itemDrag();
  83.             }
  84.         }
  85.         event->acceptProposedAction();
  86.     }
  87.     QListWidget::dropEvent(event);
  88. }
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listbox.jpeg