dragwidget.cpp Example File
^{draganddrop/draggabletext/dragwidget.cpp}

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    **
    ** Copyright (C) 2005-2005 Trolltech AS. All rights reserved.
    **
    ** This file is part of the documentation of the Qt Toolkit.
    **
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** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
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    #include <QtGui>

    #include "draglabel.h"
    #include "dragwidget.h"

    DragWidget::DragWidget(QWidget *parent)
        : QWidget(parent)
    {
        QFile dictionaryFile(":/dictionary/words.txt");
        dictionaryFile.open(QIODevice::ReadOnly);
        QTextStream inputStream(&dictionaryFile);

        int x = 5;
        int y = 5;

        while (!inputStream.atEnd()) {
            QString word;
            inputStream >> word;
            if (!word.isEmpty()) {
                DragLabel *wordLabel = new DragLabel(word, this);
                wordLabel->move(x, y);
                wordLabel->show();
                x += wordLabel->width() + 2;
                if (x >= 195) {
                    x = 5;
                    y += wordLabel->height() + 2;
                }
            }
        }

        QPalette newPalette = palette();
        newPalette.setColor(QPalette::Background, Qt::white);
        setPalette(newPalette);

        setAcceptDrops(true);
        setMinimumSize(400, qMax(200, y));
        setWindowTitle(tr("Draggable Text"));
    }

    void DragWidget::dragEnterEvent(QDragEnterEvent *event)
    {
        if (event->mimeData()->hasText())
            event->acceptProposedAction();
        else
            event->ignore();
    }

    void DragWidget::dropEvent(QDropEvent *event)
    {
        if (event->mimeData()->hasText()) {
            QStringList pieces = event->mimeData()->text().split(QRegExp("\\s+"),
                                 QString::SkipEmptyParts);
            QPoint position = event->pos();

            foreach (QString piece, pieces) {
                DragLabel *newLabel = new DragLabel(piece, this);
                newLabel->move(position);
                newLabel->show();

                position += QPoint(newLabel->width(), 0);
            }

            if (children().contains(event->source())) {
                event->setDropAction(Qt::MoveAction);
                event->accept();
            } else {
                event->acceptProposedAction();
            }
        } else {
            event->ignore();
        }
    }