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/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
** the names of its contributors may be used to endorse or promote
** products derived from this software without specific prior written
** permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtGui>
#include "dragwidget.h"
DragWidget::DragWidget(QWidget *parent)
: QFrame(parent)
{
setFrameStyle(QFrame::StyledPanel | QFrame::Sunken);
dragDropLabel = new QLabel("", this);
dragDropLabel->setAlignment(Qt::AlignHCenter);
QHBoxLayout *layout = new QHBoxLayout(this);
layout->addStretch(0);
layout->addWidget(dragDropLabel);
layout->addStretch(0);
setAcceptDrops(true);
}
// Accept all actions, but deal with them separately later.
//! [0]
void DragWidget::dragEnterEvent(QDragEnterEvent *event)
{
event->acceptProposedAction();
}
//! [0]
//! [1]
void DragWidget::dropEvent(QDropEvent *event)
{
if (event->source() == this && event->possibleActions() & Qt::MoveAction)
return;
//! [1]
//! [2]
if (event->proposedAction() == Qt::MoveAction) {
event->acceptProposedAction();
// Process the data from the event.
//! [2]
emit dragResult(tr("The data was moved here."));
//! [3]
} else if (event->proposedAction() == Qt::CopyAction) {
event->acceptProposedAction();
// Process the data from the event.
//! [3]
emit dragResult(tr("The data was copied here."));
//! [4]
} else {
// Ignore the drop.
return;
}
//! [4]
// End of quote
emit mimeTypes(event->mimeData()->formats());
setData(event->mimeData()->formats()[0],
event->mimeData()->data(event->mimeData()->formats()[0]));
//! [5]
}
//! [5]
//! [6]
void DragWidget::mousePressEvent(QMouseEvent *event)
{
if (event->button() == Qt::LeftButton)
dragStartPosition = event->pos();
}
//! [6]
//! [7]
void DragWidget::mouseMoveEvent(QMouseEvent *event)
{
if (!(event->buttons() & Qt::LeftButton))
return;
if ((event->pos() - dragStartPosition).manhattanLength()
< QApplication::startDragDistance())
return;
QDrag *drag = new QDrag(this);
QMimeData *mimeData = new QMimeData;
mimeData->setData(mimeType, data);
drag->setMimeData(mimeData);
Qt::DropAction dropAction = drag->exec(Qt::CopyAction | Qt::MoveAction);
//! [7]
switch (dropAction) {
case Qt::CopyAction:
emit dragResult(tr("The text was copied."));
break;
case Qt::MoveAction:
emit dragResult(tr("The text was moved."));
break;
default:
emit dragResult(tr("Unknown action."));
break;
}
//! [8]
}
//! [8]
void DragWidget::setData(const QString &mimetype, const QByteArray &newData)
{
mimeType = mimetype;
data = QByteArray(newData);
dragDropLabel->setText(tr("%1 bytes").arg(data.size()));
QStringList formats;
formats << mimetype;
emit mimeTypes(formats);
}
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