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     2 **

     3 ** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).

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     7 ** This file is part of the examples of the Qt Toolkit.

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     9 ** $QT_BEGIN_LICENSE:LGPL$

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    16 ** GNU Lesser General Public License Usage

    17 ** Alternatively, this file may be used under the terms of the GNU Lesser

    18 ** General Public License version 2.1 as published by the Free Software

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    38 ** $QT_END_LICENSE$

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    40 ****************************************************************************/

    41 

    42 #include <QtGui>

    43 

    44 #include "dragwidget.h"

    45 

    46 //! [0]

    47 DragWidget::DragWidget(QWidget *parent)

    48     : QFrame(parent)

    49 {

    50     setMinimumSize(200, 200);

    51     setFrameStyle(QFrame::Sunken | QFrame::StyledPanel);

    52     setAcceptDrops(true);

    53 

    54     QLabel *boatIcon = new QLabel(this);

    55     boatIcon->setPixmap(QPixmap(":/images/boat.png"));

    56     boatIcon->move(20, 20);

    57     boatIcon->show();

    58     boatIcon->setAttribute(Qt::WA_DeleteOnClose);

    59 

    60     QLabel *carIcon = new QLabel(this);

    61     carIcon->setPixmap(QPixmap(":/images/car.png"));

    62     carIcon->move(120, 20);

    63     carIcon->show();

    64     carIcon->setAttribute(Qt::WA_DeleteOnClose);

    65 

    66     QLabel *houseIcon = new QLabel(this);

    67     houseIcon->setPixmap(QPixmap(":/images/house.png"));

    68     houseIcon->move(20, 120);

    69     houseIcon->show();

    70     houseIcon->setAttribute(Qt::WA_DeleteOnClose);

    71 }

    72 //! [0]

    73 

    74 void DragWidget::dragEnterEvent(QDragEnterEvent *event)

    75 {

    76     if (event->mimeData()->hasFormat("application/x-dnditemdata")) {

    77         if (event->source() == this) {

    78             event->setDropAction(Qt::MoveAction);

    79             event->accept();

    80         } else {

    81             event->acceptProposedAction();

    82         }

    83     } else {

    84         event->ignore();

    85     }

    86 }

    87 

    88 void DragWidget::dragMoveEvent(QDragMoveEvent *event)

    89 {

    90     if (event->mimeData()->hasFormat("application/x-dnditemdata")) {

    91         if (event->source() == this) {

    92             event->setDropAction(Qt::MoveAction);

    93             event->accept();

    94         } else {

    95             event->acceptProposedAction();

    96         }

    97     } else {

    98         event->ignore();

    99     }

   100 }

   101 

   102 void DragWidget::dropEvent(QDropEvent *event)

   103 {

   104     if (event->mimeData()->hasFormat("application/x-dnditemdata")) {

   105         QByteArray itemData = event->mimeData()->data("application/x-dnditemdata");

   106         QDataStream dataStream(&itemData, QIODevice::ReadOnly);

   107         

   108         QPixmap pixmap;

   109         QPoint offset;

   110         dataStream >> pixmap >> offset;

   111 

   112         QLabel *newIcon = new QLabel(this);

   113         newIcon->setPixmap(pixmap);

   114         newIcon->move(event->pos() - offset);

   115         newIcon->show();

   116         newIcon->setAttribute(Qt::WA_DeleteOnClose);

   117 

   118         if (event->source() == this) {

   119             event->setDropAction(Qt::MoveAction);

   120             event->accept();

   121         } else {

   122             event->acceptProposedAction();

   123         }

   124     } else {

   125         event->ignore();

   126     }

   127 }

   128 

   129 //! [1]

   130 void DragWidget::mousePressEvent(QMouseEvent *event)

   131 {

   132     QLabel *child = static_cast<QLabel*>(childAt(event->pos()));

   133     if (!child)

   134         return;

   135 

   136     QPixmap pixmap = *child->pixmap();

   137 

   138     QByteArray itemData;

   139     QDataStream dataStream(&itemData, QIODevice::WriteOnly);

   140     dataStream << pixmap << QPoint(event->pos() - child->pos());

   141 //! [1]

   142 

   143 //! [2]

   144     QMimeData *mimeData = new QMimeData;

   145     mimeData->setData("application/x-dnditemdata", itemData);

   146 //! [2]

   147         

   148 //! [3]

   149     QDrag *drag = new QDrag(this);

   150     drag->setMimeData(mimeData);

   151     drag->setPixmap(pixmap);

   152     drag->setHotSpot(event->pos() - child->pos());

   153 //! [3]

   154 

   155     QPixmap tempPixmap = pixmap;

   156     QPainter painter;

   157     painter.begin(&tempPixmap);

   158     painter.fillRect(pixmap.rect(), QColor(127, 127, 127, 127));

   159     painter.end();

   160 

   161     child->setPixmap(tempPixmap);

   162 

   163     if (drag->exec(Qt::CopyAction | Qt::MoveAction, Qt::CopyAction) == Qt::MoveAction)

   164         child->close();

   165     else {

   166         child->show();

   167         child->setPixmap(pixmap);

   168     }

   169 }