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++ // Copyright (C) 2016 The Qt Company Ltd.
++ // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
++
++ #include "diagramscene.h"
++ #include "diagramitem.h"
++
++ #include <QGraphicsSceneMouseEvent>
++
++ DiagramScene::DiagramScene(QObject *parent)
++ : QGraphicsScene(parent)
++ {}
++
++ void DiagramScene::mousePressEvent(QGraphicsSceneMouseEvent *event)
++ {
++ QPointF mousePos(event->buttonDownScenePos(Qt::LeftButton).x(),
++ event->buttonDownScenePos(Qt::LeftButton).y());
++ const QList<QGraphicsItem *> itemList = items(mousePos);
++ movingItem = itemList.isEmpty() ? nullptr : itemList.first();
++
++ if (movingItem != nullptr && event->button() == Qt::LeftButton)
++ oldPos = movingItem->pos();
++
++ clearSelection();
++ QGraphicsScene::mousePressEvent(event);
++ }
++
++ void DiagramScene::mouseReleaseEvent(QGraphicsSceneMouseEvent *event)
++ {
++ if (movingItem != nullptr && event->button() == Qt::LeftButton) {
++ if (oldPos != movingItem->pos())
++ emit itemMoved(qgraphicsitem_cast<DiagramItem *>(movingItem),
++ oldPos);
++ movingItem = nullptr;
++ }
++ QGraphicsScene::mouseReleaseEvent(event);
++ }