Qt 4.3: droparea.cpp Example File (draganddrop/dropsite/droparea.cpp)

|  | Home · All Classes · Main Classes · Grouped Classes · Modules · Functions |

# droparea.cpp Example File
draganddrop/dropsite/droparea.cpp

     /****************************************************************************
     **
     ** Copyright (C) 2005-2007 Trolltech ASA. All rights reserved.
     **
     ** This file is part of the example classes 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://trolltech.com/products/qt/licenses/licensing/opensource/
     **
     ** If you are unsure which license is appropriate for your use, please
     ** review the following information:
     ** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
     ** or contact the sales department at sales@trolltech.com.
     **
     ** In addition, as a special exception, Trolltech gives you certain
     ** additional rights. These rights are described in the Trolltech GPL
     ** Exception version 1.0, which can be found at
     ** http://www.trolltech.com/products/qt/gplexception/ and in the file
     ** GPL_EXCEPTION.txt in this package.
     **
     ** In addition, as a special exception, Trolltech, as the sole copyright
     ** holder for Qt Designer, grants users of the Qt/Eclipse Integration
     ** plug-in the right for the Qt/Eclipse Integration to link to
     ** functionality provided by Qt Designer and its related libraries.
     **
     ** Trolltech reserves all rights not expressly granted herein.
     **
     ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
     ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
     **
     ****************************************************************************/

     #include <QtGui>

     #include "droparea.h"

     DropArea::DropArea(QWidget *parent)
         : QLabel(parent)
     {
         setMinimumSize(200, 200);
         setFrameStyle(QFrame::Sunken | QFrame::StyledPanel);
         setAlignment(Qt::AlignCenter);
         setAcceptDrops(true);
         setAutoFillBackground(true);
         clear();
     }

     void DropArea::dragEnterEvent(QDragEnterEvent *event)
     {
         setText(tr("<drop content>"));
         setBackgroundRole(QPalette::Highlight);

         event->acceptProposedAction();
         emit changed(event->mimeData());
     }

     void DropArea::dragMoveEvent(QDragMoveEvent *event)
     {
         event->acceptProposedAction();
     }

     void DropArea::dropEvent(QDropEvent *event)
     {
         const QMimeData *mimeData = event->mimeData();

         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"));
         }

         setBackgroundRole(QPalette::Dark);
         event->acceptProposedAction();
     }

     void DropArea::dragLeaveEvent(QDragLeaveEvent *event)
     {
         clear();
         event->accept();
     }

     void DropArea::clear()
     {
         setText(tr("<drop content>"));
         setBackgroundRole(QPalette::Dark);

         emit changed();
     }