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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 "arrow.h"
#include <QGraphicsSceneMouseEvent>
#include <QTextCursor>
//! [0]
DiagramScene::DiagramScene(QMenu *itemMenu, QObject *parent)
: QGraphicsScene(parent)
{
myItemMenu = itemMenu;
myMode = MoveItem;
myItemType = DiagramItem::Step;
line = nullptr;
textItem = nullptr;
myItemColor = Qt::white;
myTextColor = Qt::black;
myLineColor = Qt::black;
}
//! [0]
//! [1]
void DiagramScene::setLineColor(const QColor &color)
{
myLineColor = color;
if (isItemChange(Arrow::Type)) {
Arrow *item = qgraphicsitem_cast<Arrow *>(selectedItems().first());
item->setColor(myLineColor);
update();
}
}
//! [1]
//! [2]
void DiagramScene::setTextColor(const QColor &color)
{
myTextColor = color;
if (isItemChange(DiagramTextItem::Type)) {
DiagramTextItem *item = qgraphicsitem_cast<DiagramTextItem *>(selectedItems().first());
item->setDefaultTextColor(myTextColor);
}
}
//! [2]
//! [3]
void DiagramScene::setItemColor(const QColor &color)
{
myItemColor = color;
if (isItemChange(DiagramItem::Type)) {
DiagramItem *item = qgraphicsitem_cast<DiagramItem *>(selectedItems().first());
item->setBrush(myItemColor);
}
}
//! [3]
//! [4]
void DiagramScene::setFont(const QFont &font)
{
myFont = font;
if (isItemChange(DiagramTextItem::Type)) {
QGraphicsTextItem *item = qgraphicsitem_cast<DiagramTextItem *>(selectedItems().first());
//At this point the selection can change so the first selected item might not be a DiagramTextItem
if (item)
item->setFont(myFont);
}
}
//! [4]
void DiagramScene::setMode(Mode mode)
{
myMode = mode;
}
void DiagramScene::setItemType(DiagramItem::DiagramType type)
{
myItemType = type;
}
//! [5]
void DiagramScene::editorLostFocus(DiagramTextItem *item)
{
QTextCursor cursor = item->textCursor();
cursor.clearSelection();
item->setTextCursor(cursor);
if (item->toPlainText().isEmpty()) {
removeItem(item);
item->deleteLater();
}
}
//! [5]
//! [6]
void DiagramScene::mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent)
{
if (mouseEvent->button() != Qt::LeftButton)
return;
DiagramItem *item;
switch (myMode) {
case InsertItem:
item = new DiagramItem(myItemType, myItemMenu);
item->setBrush(myItemColor);
addItem(item);
item->setPos(mouseEvent->scenePos());
emit itemInserted(item);
break;
//! [6] //! [7]
case InsertLine:
line = new QGraphicsLineItem(QLineF(mouseEvent->scenePos(),
mouseEvent->scenePos()));
line->setPen(QPen(myLineColor, 2));
addItem(line);
break;
//! [7] //! [8]
case InsertText:
textItem = new DiagramTextItem();
textItem->setFont(myFont);
textItem->setTextInteractionFlags(Qt::TextEditorInteraction);
textItem->setZValue(1000.0);
connect(textItem, &DiagramTextItem::lostFocus,
this, &DiagramScene::editorLostFocus);
connect(textItem, &DiagramTextItem::selectedChange,
this, &DiagramScene::itemSelected);
addItem(textItem);
textItem->setDefaultTextColor(myTextColor);
textItem->setPos(mouseEvent->scenePos());
emit textInserted(textItem);
//! [8] //! [9]
default:
;
}
QGraphicsScene::mousePressEvent(mouseEvent);
}
//! [9]
//! [10]
void DiagramScene::mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent)
{
if (myMode == InsertLine && line != nullptr) {
QLineF newLine(line->line().p1(), mouseEvent->scenePos());
line->setLine(newLine);
} else if (myMode == MoveItem) {
QGraphicsScene::mouseMoveEvent(mouseEvent);
}
}
//! [10]
//! [11]
void DiagramScene::mouseReleaseEvent(QGraphicsSceneMouseEvent *mouseEvent)
{
if (line != nullptr && myMode == InsertLine) {
QList<QGraphicsItem *> startItems = items(line->line().p1());
if (startItems.count() && startItems.first() == line)
startItems.removeFirst();
QList<QGraphicsItem *> endItems = items(line->line().p2());
if (endItems.count() && endItems.first() == line)
endItems.removeFirst();
removeItem(line);
delete line;
//! [11] //! [12]
if (startItems.count() > 0 && endItems.count() > 0 &&
startItems.first()->type() == DiagramItem::Type &&
endItems.first()->type() == DiagramItem::Type &&
startItems.first() != endItems.first()) {
DiagramItem *startItem = qgraphicsitem_cast<DiagramItem *>(startItems.first());
DiagramItem *endItem = qgraphicsitem_cast<DiagramItem *>(endItems.first());
Arrow *arrow = new Arrow(startItem, endItem);
arrow->setColor(myLineColor);
startItem->addArrow(arrow);
endItem->addArrow(arrow);
arrow->setZValue(-1000.0);
addItem(arrow);
arrow->updatePosition();
}
}
//! [12] //! [13]
line = nullptr;
QGraphicsScene::mouseReleaseEvent(mouseEvent);
}
//! [13]
//! [14]
bool DiagramScene::isItemChange(int type) const
{
const QList<QGraphicsItem *> items = selectedItems();
const auto cb = [type](const QGraphicsItem *item) { return item->type() == type; };
return std::find_if(items.begin(), items.end(), cb) != items.end();
}
//! [14]
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