qt5base-lts/examples/widgets/draganddrop/dropsite/droparea.cpp

128 lines
4.1 KiB
C++
Raw Normal View History

/****************************************************************************
**
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the examples 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 Digia Plc 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 "droparea.h"
#include <QDragEnterEvent>
#include <QMimeData>
//! [DropArea constructor]
DropArea::DropArea(QWidget *parent)
: QLabel(parent)
{
setMinimumSize(200, 200);
setFrameStyle(QFrame::Sunken | QFrame::StyledPanel);
setAlignment(Qt::AlignCenter);
setAcceptDrops(true);
setAutoFillBackground(true);
clear();
}
//! [DropArea constructor]
//! [dragEnterEvent() function]
void DropArea::dragEnterEvent(QDragEnterEvent *event)
{
setText(tr("<drop content>"));
setBackgroundRole(QPalette::Highlight);
event->acceptProposedAction();
emit changed(event->mimeData());
}
//! [dragEnterEvent() function]
//! [dragMoveEvent() function]
void DropArea::dragMoveEvent(QDragMoveEvent *event)
{
event->acceptProposedAction();
}
//! [dragMoveEvent() function]
//! [dropEvent() function part1]
void DropArea::dropEvent(QDropEvent *event)
{
const QMimeData *mimeData = event->mimeData();
//! [dropEvent() function part1]
//! [dropEvent() function part2]
if (mimeData->hasImage()) {
setPixmap(qvariant_cast<QPixmap>(mimeData->imageData()));
} else if (mimeData->hasHtml()) {
setText(mimeData->html());
setTextFormat(Qt::RichText);
} else if (mimeData->hasText()) {
setText(mimeData->text());
setTextFormat(Qt::PlainText);
} else if (mimeData->hasUrls()) {
QList<QUrl> urlList = mimeData->urls();
QString text;
for (int i = 0; i < urlList.size() && i < 32; ++i) {
QString url = urlList.at(i).path();
text += url + QString("\n");
}
setText(text);
} else {
setText(tr("Cannot display data"));
}
//! [dropEvent() function part2]
//! [dropEvent() function part3]
setBackgroundRole(QPalette::Dark);
event->acceptProposedAction();
}
//! [dropEvent() function part3]
//! [dragLeaveEvent() function]
void DropArea::dragLeaveEvent(QDragLeaveEvent *event)
{
clear();
event->accept();
}
//! [dragLeaveEvent() function]
//! [clear() function]
void DropArea::clear()
{
setText(tr("<drop content>"));
setBackgroundRole(QPalette::Dark);
emit changed();
}
//! [clear() function]