QList Drag and Drop Example

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Example of the simple moving items using drag & drop betweeen two or more QListViews.

listbox.h:

#ifndef LISTBOX_H
#define LISTBOX_H

#include <QtGui>

class ListBox : public QListWidget
{
 Q_OBJECT
public:
 ListBox(QWidget *parent);
protected:
 void dragMoveEvent(QDragMoveEvent *e);
 void dropEvent(QDropEvent *event);
 void startDrag(Qt::DropActions supportedActions);
 void dragEnterEvent(QDragEnterEvent *event);
 Qt::DropAction supportedDropActions();
signals:
 void itemDroped();
};

#endif // LISTBOX_H

listbox.cpp:

#include "listbox.h"

void ListBox::dragMoveEvent(QDragMoveEvent *e)
{
 if (e->mimeData()->hasFormat("application/x-item") && e->source() != this) {
 e->setDropAction(Qt::MoveAction);
 e->accept();
 } else
 e->ignore();

}

ListBox::ListBox(QWidget *parent) : QListWidget(parent)
{
 this->setViewMode(QListView::IconMode);
 this->setIconSize(QSize(55, 55));
 this->setSelectionMode(QAbstractItemView::SingleSelection);
 this->setDragEnabled(true);
 this->setDefaultDropAction(Qt::MoveAction);
 this->setAcceptDrops(true);
 this->setDropIndicatorShown(true);
}

void ListBox::dropEvent(QDropEvent *event)
{
 if (event->mimeData()->hasFormat("application/x-item")) {
 event->accept();
 event->setDropAction(Qt::MoveAction);
 QListWidgetItem *item = new QListWidgetItem;
 QString name = event->mimeData()->data("application/x-item");
 item->setText(name);
 item->setIcon(QIcon(":/images/iString")); //set path to image
 addItem(item);
 }
 else
 event->ignore();
}

void ListBox::startDrag(Qt::DropActions supportedActions)
{
 QListWidgetItem *item = currentItem();
 QMimeData *mimeData = new QMimeData;
 QByteArray ba;
 ba = item->text().toLatin1().data();
 mimeData->setData("application/x-item", ba);
 QDrag *drag = new QDrag(this);
 drag->setMimeData(mimeData);
 if (drag->exec(Qt::MoveAction) == Qt::MoveAction) {
 delete takeItem(row(item));
 emit itemDroped();
 }
}

void ListBox::dragEnterEvent(QDragEnterEvent *event)
{
 if (event->mimeData()->hasFormat("application/x-item"))
 event->accept();
 else
 event->ignore();
}

Qt::DropAction ListBox::supportedDropActions()
{
 return Qt::MoveAction;
}