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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "draglabel.h"
#include "dragwidget.h"
#include <QtWidgets>
static inline QString fridgetMagnetsMimeType() { return QStringLiteral("application/x-fridgemagnet"); }
//! [0]
DragWidget::DragWidget(QWidget *parent)
: QWidget(parent)
{
QFile dictionaryFile(QStringLiteral(":/dictionary/words.txt"));
dictionaryFile.open(QFile::ReadOnly);
QTextStream inputStream(&dictionaryFile);
//! [0]
//! [1]
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();
wordLabel->setAttribute(Qt::WA_DeleteOnClose);
x += wordLabel->width() + 2;
if (x >= 245) {
x = 5;
y += wordLabel->height() + 2;
}
}
}
//! [1]
//! [2]
QPalette newPalette = palette();
newPalette.setColor(QPalette::Window, Qt::white);
setPalette(newPalette);
setMinimumSize(400, qMax(200, y));
setWindowTitle(tr("Fridge Magnets"));
//! [2] //! [3]
setAcceptDrops(true);
}
//! [3]
//! [4]
void DragWidget::dragEnterEvent(QDragEnterEvent *event)
{
//! [4] //! [5]
if (event->mimeData()->hasFormat(fridgetMagnetsMimeType())) {
if (children().contains(event->source())) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
event->acceptProposedAction();
//! [5] //! [6]
}
//! [6] //! [7]
} else if (event->mimeData()->hasText()) {
event->acceptProposedAction();
} else {
event->ignore();
}
}
//! [7]
//! [8]
void DragWidget::dragMoveEvent(QDragMoveEvent *event)
{
if (event->mimeData()->hasFormat(fridgetMagnetsMimeType())) {
if (children().contains(event->source())) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
event->acceptProposedAction();
}
} else if (event->mimeData()->hasText()) {
event->acceptProposedAction();
} else {
event->ignore();
}
}
//! [8]
//! [9]
void DragWidget::dropEvent(QDropEvent *event)
{
if (event->mimeData()->hasFormat(fridgetMagnetsMimeType())) {
const QMimeData *mime = event->mimeData();
//! [9] //! [10]
QByteArray itemData = mime->data(fridgetMagnetsMimeType());
QDataStream dataStream(&itemData, QIODevice::ReadOnly);
QString text;
QPoint offset;
dataStream >> text >> offset;
//! [10]
//! [11]
DragLabel *newLabel = new DragLabel(text, this);
newLabel->move(event->position().toPoint() - offset);
newLabel->show();
newLabel->setAttribute(Qt::WA_DeleteOnClose);
if (event->source() == this) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
event->acceptProposedAction();
}
//! [11] //! [12]
} else if (event->mimeData()->hasText()) {
QStringList pieces = event->mimeData()->text().split(
QRegularExpression(QStringLiteral("\\s+")), Qt::SkipEmptyParts);
QPoint position = event->position().toPoint();
for (const QString &piece : pieces) {
DragLabel *newLabel = new DragLabel(piece, this);
newLabel->move(position);
newLabel->show();
newLabel->setAttribute(Qt::WA_DeleteOnClose);
position += QPoint(newLabel->width(), 0);
}
event->acceptProposedAction();
} else {
event->ignore();
}
}
//! [12]
//! [13]
void DragWidget::mousePressEvent(QMouseEvent *event)
{
//! [13]
//! [14]
DragLabel *child = static_cast<DragLabel*>(childAt(event->position().toPoint()));
if (!child)
return;
QPoint hotSpot = event->position().toPoint() - child->pos();
QByteArray itemData;
QDataStream dataStream(&itemData, QIODevice::WriteOnly);
dataStream << child->labelText() << QPoint(hotSpot);
//! [14]
//! [15]
QMimeData *mimeData = new QMimeData;
mimeData->setData(fridgetMagnetsMimeType(), itemData);
mimeData->setText(child->labelText());
//! [15]
//! [16]
QDrag *drag = new QDrag(this);
drag->setMimeData(mimeData);
drag->setPixmap(child->pixmap(Qt::ReturnByValue));
drag->setHotSpot(hotSpot);
child->hide();
//! [16]
//! [17]
if (drag->exec(Qt::MoveAction | Qt::CopyAction, Qt::CopyAction) == Qt::MoveAction)
child->close();
else
child->show();
}
//! [17]
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