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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "diagramitem.h"
#include "arrow.h"
#include <QGraphicsScene>
#include <QGraphicsSceneContextMenuEvent>
#include <QMenu>
#include <QPainter>
//! [0]
DiagramItem::DiagramItem(DiagramType diagramType, QMenu *contextMenu,
QGraphicsItem *parent)
: QGraphicsPolygonItem(parent), myDiagramType(diagramType)
, myContextMenu(contextMenu)
{
QPainterPath path;
switch (myDiagramType) {
case StartEnd:
path.moveTo(200, 50);
path.arcTo(150, 0, 50, 50, 0, 90);
path.arcTo(50, 0, 50, 50, 90, 90);
path.arcTo(50, 50, 50, 50, 180, 90);
path.arcTo(150, 50, 50, 50, 270, 90);
path.lineTo(200, 25);
myPolygon = path.toFillPolygon();
break;
case Conditional:
myPolygon << QPointF(-100, 0) << QPointF(0, 100)
<< QPointF(100, 0) << QPointF(0, -100)
<< QPointF(-100, 0);
break;
case Step:
myPolygon << QPointF(-100, -100) << QPointF(100, -100)
<< QPointF(100, 100) << QPointF(-100, 100)
<< QPointF(-100, -100);
break;
default:
myPolygon << QPointF(-120, -80) << QPointF(-70, 80)
<< QPointF(120, 80) << QPointF(70, -80)
<< QPointF(-120, -80);
break;
}
setPolygon(myPolygon);
setFlag(QGraphicsItem::ItemIsMovable, true);
setFlag(QGraphicsItem::ItemIsSelectable, true);
setFlag(QGraphicsItem::ItemSendsGeometryChanges, true);
}
//! [0]
//! [1]
void DiagramItem::removeArrow(Arrow *arrow)
{
arrows.removeAll(arrow);
}
//! [1]
//! [2]
void DiagramItem::removeArrows()
{
// need a copy here since removeArrow() will
// modify the arrows container
const auto arrowsCopy = arrows;
for (Arrow *arrow : arrowsCopy) {
arrow->startItem()->removeArrow(arrow);
arrow->endItem()->removeArrow(arrow);
scene()->removeItem(arrow);
delete arrow;
}
}
//! [2]
//! [3]
void DiagramItem::addArrow(Arrow *arrow)
{
arrows.append(arrow);
}
//! [3]
//! [4]
QPixmap DiagramItem::image() const
{
QPixmap pixmap(250, 250);
pixmap.fill(Qt::transparent);
QPainter painter(&pixmap);
painter.setPen(QPen(Qt::black, 8));
painter.translate(125, 125);
painter.drawPolyline(myPolygon);
return pixmap;
}
//! [4]
//! [5]
void DiagramItem::contextMenuEvent(QGraphicsSceneContextMenuEvent *event)
{
scene()->clearSelection();
setSelected(true);
myContextMenu->popup(event->screenPos());
}
//! [5]
//! [6]
QVariant DiagramItem::itemChange(GraphicsItemChange change, const QVariant &value)
{
if (change == QGraphicsItem::ItemPositionChange) {
for (Arrow *arrow : std::as_const(arrows))
arrow->updatePosition();
}
return value;
}
//! [6]
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