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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "commands.h"
#include "diagramitem.h"
#include <QGraphicsScene>
//! [0]
MoveCommand::MoveCommand(DiagramItem *diagramItem, const QPointF &oldPos,
QUndoCommand *parent)
: QUndoCommand(parent), myDiagramItem(diagramItem)
, myOldPos(oldPos), newPos(diagramItem->pos())
{
}
//! [0]
//! [1]
bool MoveCommand::mergeWith(const QUndoCommand *command)
{
const MoveCommand *moveCommand = static_cast<const MoveCommand *>(command);
DiagramItem *item = moveCommand->myDiagramItem;
if (myDiagramItem != item)
return false;
newPos = item->pos();
setText(QObject::tr("Move %1")
.arg(createCommandString(myDiagramItem, newPos)));
return true;
}
//! [1]
//! [2]
void MoveCommand::undo()
{
myDiagramItem->setPos(myOldPos);
myDiagramItem->scene()->update();
setText(QObject::tr("Move %1")
.arg(createCommandString(myDiagramItem, newPos)));
}
//! [2]
//! [3]
void MoveCommand::redo()
{
myDiagramItem->setPos(newPos);
setText(QObject::tr("Move %1")
.arg(createCommandString(myDiagramItem, newPos)));
}
//! [3]
//! [4]
DeleteCommand::DeleteCommand(QGraphicsScene *scene, QUndoCommand *parent)
: QUndoCommand(parent), myGraphicsScene(scene)
{
QList<QGraphicsItem *> list = myGraphicsScene->selectedItems();
list.first()->setSelected(false);
myDiagramItem = static_cast<DiagramItem *>(list.first());
setText(QObject::tr("Delete %1")
.arg(createCommandString(myDiagramItem, myDiagramItem->pos())));
}
//! [4]
//! [5]
void DeleteCommand::undo()
{
myGraphicsScene->addItem(myDiagramItem);
myGraphicsScene->update();
}
//! [5]
//! [6]
void DeleteCommand::redo()
{
myGraphicsScene->removeItem(myDiagramItem);
}
//! [6]
//! [7]
AddCommand::AddCommand(DiagramItem::DiagramType addType,
QGraphicsScene *scene, QUndoCommand *parent)
: QUndoCommand(parent), myGraphicsScene(scene)
{
static int itemCount = 0;
myDiagramItem = new DiagramItem(addType);
initialPosition = QPointF((itemCount * 15) % int(scene->width()),
(itemCount * 15) % int(scene->height()));
scene->update();
++itemCount;
setText(QObject::tr("Add %1")
.arg(createCommandString(myDiagramItem, initialPosition)));
}
//! [7]
AddCommand::~AddCommand()
{
if (!myDiagramItem->scene())
delete myDiagramItem;
}
//! [8]
void AddCommand::undo()
{
myGraphicsScene->removeItem(myDiagramItem);
myGraphicsScene->update();
}
//! [8]
//! [9]
void AddCommand::redo()
{
myGraphicsScene->addItem(myDiagramItem);
myDiagramItem->setPos(initialPosition);
myGraphicsScene->clearSelection();
myGraphicsScene->update();
}
//! [9]
QString createCommandString(DiagramItem *item, const QPointF &pos)
{
return QObject::tr("%1 at (%2, %3)")
.arg(item->diagramType() == DiagramItem::Box ? "Box" : "Triangle")
.arg(pos.x()).arg(pos.y());
}
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