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++ // Copyright (C) 2016 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #include <QtWidgets>
++
++ #include "dragwidget.h"
++
++ static QLabel *createDragLabel(const QString &text, QWidget *parent)
++ {
++ QLabel *label = new QLabel(text, parent);
++ label->setAutoFillBackground(true);
++ label->setFrameShape(QFrame::Panel);
++ label->setFrameShadow(QFrame::Raised);
++ return label;
++ }
++
++ static QString hotSpotMimeDataKey() { return QStringLiteral("application/x-hotspot"); }
++
++ DragWidget::DragWidget(QWidget *parent)
++ : QWidget(parent)
++ {
++ QFile dictionaryFile(QStringLiteral(":/dictionary/words.txt"));
++ if (!dictionaryFile.open(QIODevice::ReadOnly)) {
++ // This would be a build problem, as the dictionary is in the
++ // resource system.
++ qFatal("Could not open the dictionary file: %s",
++ qPrintable(dictionaryFile.errorString()));
++ }
++ QTextStream inputStream(&dictionaryFile);
++
++ int x = 5;
++ int y = 5;
++
++ while (!inputStream.atEnd()) {
++ QString word;
++ inputStream >> word;
++ if (!word.isEmpty()) {
++ QLabel *wordLabel = createDragLabel(word, this);
++ wordLabel->move(x, y);
++ wordLabel->show();
++ wordLabel->setAttribute(Qt::WA_DeleteOnClose);
++ x += wordLabel->width() + 2;
++ if (x >= 245) {
++ x = 5;
++ y += wordLabel->height() + 2;
++ }
++ }
++ }
++
++ setAcceptDrops(true);
++ setMinimumSize(400, qMax(200, y));
++ setWindowTitle(tr("Draggable Text"));
++ }
++
++ void DragWidget::dragEnterEvent(QDragEnterEvent *event)
++ {
++ if (event->mimeData()->hasText()) {
++ if (event->source() == this) {
++ event->setDropAction(Qt::MoveAction);
++ event->accept();
++ } else {
++ event->acceptProposedAction();
++ }
++ } else {
++ event->ignore();
++ }
++ }
++
++ void DragWidget::dropEvent(QDropEvent *event)
++ {
++ if (event->mimeData()->hasText()) {
++ const QMimeData *mime = event->mimeData();
++ QStringList pieces = mime->text().split(QRegularExpression(QStringLiteral("\\s+")),
++ Qt::SkipEmptyParts);
++ QPoint position = event->position().toPoint();
++ QPoint hotSpot;
++
++ QByteArrayList hotSpotPos = mime->data(hotSpotMimeDataKey()).split(' ');
++ if (hotSpotPos.size() == 2) {
++ hotSpot.setX(hotSpotPos.first().toInt());
++ hotSpot.setY(hotSpotPos.last().toInt());
++ }
++
++ for (const QString &piece : pieces) {
++ QLabel *newLabel = createDragLabel(piece, this);
++ newLabel->move(position - hotSpot);
++ newLabel->show();
++ newLabel->setAttribute(Qt::WA_DeleteOnClose);
++
++ position += QPoint(newLabel->width(), 0);
++ }
++
++ if (event->source() == this) {
++ event->setDropAction(Qt::MoveAction);
++ event->accept();
++ } else {
++ event->acceptProposedAction();
++ }
++ } else {
++ event->ignore();
++ }
++ for (QWidget *widget : findChildren<QWidget *>()) {
++ if (!widget->isVisible())
++ widget->deleteLater();
++ }
++ }
++
++ void DragWidget::mousePressEvent(QMouseEvent *event)
++ {
++ QLabel *child = qobject_cast<QLabel*>(childAt(event->position().toPoint()));
++ if (!child)
++ return;
++
++ QPoint hotSpot = event->position().toPoint() - child->pos();
++
++ QMimeData *mimeData = new QMimeData;
++ mimeData->setText(child->text());
++ mimeData->setData(hotSpotMimeDataKey(),
++ QByteArray::number(hotSpot.x()) + ' ' + QByteArray::number(hotSpot.y()));
++
++ qreal dpr = window()->windowHandle()->devicePixelRatio();
++ QPixmap pixmap(child->size() * dpr);
++ pixmap.setDevicePixelRatio(dpr);
++ child->render(&pixmap);
++
++ QDrag *drag = new QDrag(this);
++ drag->setMimeData(mimeData);
++ drag->setPixmap(pixmap);
++ drag->setHotSpot(hotSpot);
++
++ Qt::DropAction dropAction = drag->exec(Qt::CopyAction | Qt::MoveAction, Qt::CopyAction);
++
++ if (dropAction == Qt::MoveAction)
++ child->close();
++ }