pieceslist.cpp Example File
draganddrop/puzzle/pieceslist.cpp
/****************************************************************************
**
** Copyright (C) 2005-2005 Trolltech AS. All rights reserved.
**
** This file is part of the documentation of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file. Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
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** review the following information:
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** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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****************************************************************************/
#include <QtGui>
#include "pieceslist.h"
PiecesList::PiecesList(QWidget *parent)
: QListWidget(parent)
{
setDragEnabled(true);
setViewMode(QListView::IconMode);
setIconSize(QSize(60, 60));
setSpacing(10);
setAcceptDrops(true);
setDropIndicatorShown(true);
}
void PiecesList::dragEnterEvent(QDragEnterEvent *event)
{
if (event->mimeData()->hasFormat("image/x-puzzle-piece"))
event->accept();
else
event->ignore();
}
void PiecesList::dragMoveEvent(QDragMoveEvent *event)
{
if (event->mimeData()->hasFormat("image/x-puzzle-piece")) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else
event->ignore();
}
void PiecesList::dropEvent(QDropEvent *event)
{
if (event->mimeData()->hasFormat("image/x-puzzle-piece")) {
QByteArray pieceData = event->mimeData()->data("image/x-puzzle-piece");
QDataStream dataStream(&pieceData, QIODevice::ReadOnly);
QPixmap pixmap;
QPoint location;
dataStream >> pixmap >> location;
addPiece(pixmap, location);
event->setDropAction(Qt::MoveAction);
event->accept();
} else
event->ignore();
}
void PiecesList::addPiece(QPixmap pixmap, QPoint location)
{
QListWidgetItem *pieceItem = new QListWidgetItem(this);
pieceItem->setIcon(QIcon(pixmap));
pieceItem->setData(Qt::UserRole, QVariant(pixmap));
pieceItem->setData(Qt::UserRole+1, location);
pieceItem->setFlags(Qt::ItemIsEnabled | Qt::ItemIsSelectable
| Qt::ItemIsDragEnabled);
}
void PiecesList::startDrag(Qt::DropActions supportedActions)
{
QListWidgetItem *item = currentItem();
QByteArray itemData;
QDataStream dataStream(&itemData, QIODevice::WriteOnly);
QPixmap pixmap = qVariantValue<QPixmap>(item->data(Qt::UserRole));
QPoint location = item->data(Qt::UserRole+1).toPoint();
dataStream << pixmap << location;
QMimeData *mimeData = new QMimeData;
mimeData->setData("image/x-puzzle-piece", itemData);
QDrag *drag = new QDrag(this);
drag->setMimeData(mimeData);
drag->setHotSpot(QPoint(pixmap.width()/2, pixmap.height()/2));
drag->setPixmap(pixmap);
if (drag->start(Qt::MoveAction) == Qt::MoveAction)
delete takeItem(row(item));
}