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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"
//! [0]
DragWidget::DragWidget(QWidget *parent)
: QFrame(parent)
{
setMinimumSize(200, 200);
setFrameStyle(QFrame::Sunken | QFrame::StyledPanel);
setAcceptDrops(true);
QLabel *boatIcon = new QLabel(this);
boatIcon->setPixmap(QPixmap(":/images/boat.png"));
boatIcon->move(10, 10);
boatIcon->show();
boatIcon->setAttribute(Qt::WA_DeleteOnClose);
QLabel *carIcon = new QLabel(this);
carIcon->setPixmap(QPixmap(":/images/car.png"));
carIcon->move(100, 10);
carIcon->show();
carIcon->setAttribute(Qt::WA_DeleteOnClose);
QLabel *houseIcon = new QLabel(this);
houseIcon->setPixmap(QPixmap(":/images/house.png"));
houseIcon->move(10, 80);
houseIcon->show();
houseIcon->setAttribute(Qt::WA_DeleteOnClose);
}
//! [0]
void DragWidget::dragEnterEvent(QDragEnterEvent *event)
{
if (event->mimeData()->hasFormat("application/x-dnditemdata")) {
if (event->source() == this) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
event->acceptProposedAction();
}
} else {
event->ignore();
}
}
void DragWidget::dragMoveEvent(QDragMoveEvent *event)
{
if (event->mimeData()->hasFormat("application/x-dnditemdata")) {
if (event->source() == this) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
event->acceptProposedAction();
}
} else {
event->ignore();
}
}
void DragWidget::dropEvent(QDropEvent *event)
{
if (event->mimeData()->hasFormat("application/x-dnditemdata")) {
QByteArray itemData = event->mimeData()->data("application/x-dnditemdata");
QDataStream dataStream(&itemData, QIODevice::ReadOnly);
QPixmap pixmap;
QPoint offset;
dataStream >> pixmap >> offset;
QLabel *newIcon = new QLabel(this);
newIcon->setPixmap(pixmap);
newIcon->move(event->position().toPoint() - offset);
newIcon->show();
newIcon->setAttribute(Qt::WA_DeleteOnClose);
if (event->source() == this) {
event->setDropAction(Qt::MoveAction);
event->accept();
} else {
event->acceptProposedAction();
}
} else {
event->ignore();
}
}
//! [1]
void DragWidget::mousePressEvent(QMouseEvent *event)
{
QLabel *child = static_cast<QLabel*>(childAt(event->position().toPoint()));
if (!child)
return;
QPixmap pixmap = child->pixmap();
QByteArray itemData;
QDataStream dataStream(&itemData, QIODevice::WriteOnly);
dataStream << pixmap << QPoint(event->position().toPoint() - child->pos());
//! [1]
//! [2]
QMimeData *mimeData = new QMimeData;
mimeData->setData("application/x-dnditemdata", itemData);
//! [2]
//! [3]
QDrag *drag = new QDrag(this);
drag->setMimeData(mimeData);
drag->setPixmap(pixmap);
drag->setHotSpot(event->position().toPoint() - child->pos());
//! [3]
child->setParent(nullptr);
if (drag->exec(Qt::CopyAction | Qt::MoveAction, Qt::CopyAction) == Qt::MoveAction) {
delete child;
} else {
child->setParent(this);
child->move(event->position().toPoint() - drag->hotSpot());
child->show();
}
}
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