C++ parentItem函数代码示例

void QQuickMenuPopupWindow::setGeometry(int posx, int posy, int w, int h)
{
    QWindow *pw = transientParent();
    if (!pw && parentItem())
        pw = parentItem()->window();
    if (!pw)
        pw = this;
    QRect g = pw->screen()->availableVirtualGeometry();

    if (posx + w > g.right()) {
        if (qobject_cast<QQuickMenuPopupWindow *>(transientParent())) {
            // reposition submenu window on the parent menu's left side
            int submenuOverlap = pw->x() + pw->width() - posx;
            posx -= pw->width() + w - 2 * submenuOverlap;
        } else {
            posx = g.right() - w;
        }
    } else {
        posx = qMax(posx, g.left());
    }

    posy = qBound(g.top(), posy, g.bottom() - h);

    QQuickWindow::setGeometry(posx, posy, w, h);
}

QVariant PixmapItem::itemChange(GraphicsItemChange change,
                                const QVariant &value)
{
    if (change == ItemPositionChange)
    {
        // value is the new position.
        QPointF newPos = value.toPointF();
        QRectF rect = parentItem()->boundingRect();

        rect.moveLeft(boundingRect().width()*3/4*-1);
        rect.setWidth(rect.width() + boundingRect().width()*2/4 );

        rect.moveTop(boundingRect().height()*3/4*-1);
        rect.setHeight(rect.height() + boundingRect().height()*2/4 );

        CardItem *card = qgraphicsitem_cast<CardItem *>(parentItem());

        if (!rect.contains(newPos))
        {
            // Keep the item inside the scene rect.
            int newX = (int)qMin(rect.right(), qMax(newPos.x(), rect.left()));
            int newY = (int)qMin(rect.bottom(), qMax(newPos.y(), rect.top()));



            if(card->isAlign())
            {
                int gridSize = card->getGridSize();
                newX = (newX/(10*gridSize))*(10*gridSize);
                newY = (newY/(10*gridSize))*(10*gridSize);
            }

            newPos.setX(newX);
            newPos.setY(newY);
            return newPos;
        }
        else
        {
            int newX =  newPos.x();
            int newY = newPos.y();

            if(card->isAlign())
            {
                int gridSize = card->getGridSize();
                newX = newPos.x()/(10*gridSize);
                newX = newX * (10*gridSize);
                newY = newPos.y()/(10*gridSize);
                newY = newY*(10*gridSize);

            }

            newPos.setX(newX);
            newPos.setY(newY);
            return newPos;

        }
    }

    return QGraphicsItem::itemChange(change, value);
}

void ElementTitle::focusOutEvent(QFocusEvent *event)
{
	QGraphicsTextItem::focusOutEvent(event);

	QString htmlNormalizedText = toHtml().remove("\n", Qt::CaseInsensitive);

	setTextInteractionFlags(Qt::NoTextInteraction);

	parentItem()->setSelected(true);

	// Clear selection
	QTextCursor cursor = textCursor();
	cursor.clearSelection();
	setTextCursor(cursor);

	unsetCursor();

	if (mReadOnly)
		return;

	if (mOldText != toPlainText()) {
		QString value = toPlainText();
		if (mBinding == "name")
			static_cast<NodeElement*>(parentItem())->setName(value);
		else
			static_cast<NodeElement*>(parentItem())->setLogicalProperty(mBinding, value);
	}
	setHtml(htmlNormalizedText);
}

 QRectF RadicalElectron::boundingRect() const {
   if (!parentItem()) return QRectF();
   Q_D(const RadicalElectron);
   QRectF bounds(0,0,d->diameter,d->diameter);
   bounds.translate(d->linker.getShift(parentItem()->boundingRect(), bounds));
   return bounds;
 }

Cell::CellState Cell::shrinkOrGrow()
{
    int dishSize = qRound(parentItem()->boundingRect().width());
    int neighbours = 0;
    QListIterator<QGraphicsItem*> i(parentItem()->childItems());
    while (i.hasNext()) {
        QGraphicsItem *item = i.next();
        if (item != this && collidesWithItem(item))
            ++neighbours;
    }
    if (!neighbours || m_size > dishSize / 3)
        m_size *= randomReal(); // shrink - lonely or too big
    else if (neighbours < 4) // grow - happy
        m_size *= ((5 - neighbours) * randomReal());
    else // shrink - too crowded
        m_size *= ((1.0 / neighbours) + randomReal());

    QPainterPath path;
    qreal x = m_size * std::cos(AQP::radiansFromDegrees(1));
    qreal y = m_size * std::sin(AQP::radiansFromDegrees(1));
    path.moveTo(x, y);
    for (int angle = 1; angle < 360; ++angle) {
        qreal factor = m_size + ((m_size / 3) * (randomReal() - 0.5));
        x = factor * std::cos(AQP::radiansFromDegrees(angle));
        y = factor * std::sin(AQP::radiansFromDegrees(angle));
        path.lineTo(x, y);
    }
    path.closeSubpath();
    m_path = path;

    prepareGeometryChange();
    if (m_size < 5.0 && (qrand() % 20 == 0))
        return Die; // small ones randomly die
    return Live;
}

QVariant Node::itemChange(GraphicsItemChange change, const QVariant &value)
{
    switch (change)
    {
      case ItemPositionHasChanged:
        if (parentItem() != 0)
        {
            if (parentItem()->type() == Graph::Type)
            {
                Graph * graph = qgraphicsitem_cast<Graph*>(parentItem());
                Graph * tempGraph = graph;
                graph = qgraphicsitem_cast<Graph*>(graph->getRootParent());
                this->setParentItem(nullptr);
                this->setParentItem(tempGraph);
            }
            if (verbose)
                qDebug() << "node does not have a graph item parent";
        }
        foreach (Edge * edge, edgeList)
            edge->adjust();
        break;

      case ItemRotationChange:
        foreach (Edge * edge, edgeList)
            edge->adjust();
        break;

      default:
        break;
    };

    return QGraphicsItem::itemChange(change, value);
}

/*!
    \internal

    This function is called from subclasses to add a layout item \a layoutItem
    to a layout.

    It takes care of automatically reparenting graphics items, if needed.

    If \a layoutItem is a  is already in a layout, it will remove it  from that layout.

*/
void QGraphicsLayoutPrivate::addChildLayoutItem(QGraphicsLayoutItem *layoutItem)
{
    Q_Q(QGraphicsLayout);
    if (QGraphicsLayoutItem *maybeLayout = layoutItem->parentLayoutItem()) {
        if (maybeLayout->isLayout())
            removeLayoutItemFromLayout(static_cast<QGraphicsLayout*>(maybeLayout), layoutItem);
    }
    layoutItem->setParentLayoutItem(q);
    if (layoutItem->isLayout()) {
        if (QGraphicsItem *parItem = parentItem()) {
            static_cast<QGraphicsLayout*>(layoutItem)->d_func()->reparentChildItems(parItem);
        }
    } else {
        if (QGraphicsItem *item = layoutItem->graphicsItem()) {
            QGraphicsItem *newParent = parentItem();
            QGraphicsItem *oldParent = item->parentItem();
            if (oldParent == newParent || !newParent)
                return;

#ifdef QT_DEBUG
            if (oldParent && item->isWidget()) {
                QGraphicsWidget *w = static_cast<QGraphicsWidget*>(item);
                qWarning("QGraphicsLayout::addChildLayoutItem: %s \"%s\" in wrong parent; moved to correct parent",
                    w->metaObject()->className(), w->objectName().toLocal8Bit().constData());
            }
#endif

            item->setParentItem(newParent);
        }
    }
}

UIGChooserItemMachine::~UIGChooserItemMachine()
{
    /* If that item is focused: */
    if (model()->focusItem() == this)
    {
        /* Unset the focus: */
        model()->setFocusItem(0);
    }
    /* If that item is in selection list: */
    if (model()->currentItems().contains(this))
    {
        /* Remove item from the selection list: */
        model()->removeFromCurrentItems(this);
    }
    /* If that item is in navigation list: */
    if (model()->navigationList().contains(this))
    {
        /* Remove item from the navigation list: */
        model()->removeFromNavigationList(this);
    }

    /* Remove item from the parent: */
    AssertMsg(parentItem(), ("No parent set for machine-item!"));
    parentItem()->removeItem(this);
}

CanvasBezierLineMov::CanvasBezierLineMov(PortMode port_mode_, PortType port_type_, QGraphicsItem* parent) :
    QGraphicsPathItem(parent, canvas.scene)
{
    port_mode = port_mode_;
    port_type = port_type_;

    // Port position doesn't change while moving around line
    item_x = parentItem()->scenePos().x();
    item_y = parentItem()->scenePos().y();
    item_width = ((CanvasPort*)parentItem())->getPortWidth(); // FIXME

    QPen pen;

    if (port_type == PORT_TYPE_AUDIO_JACK)
        pen = QPen(canvas.theme->line_audio_jack, 2);
    else if (port_type == PORT_TYPE_MIDI_JACK)
        pen = QPen(canvas.theme->line_midi_jack, 2);
    else if (port_type == PORT_TYPE_MIDI_A2J)
        pen = QPen(canvas.theme->line_midi_a2j, 2);
    else if (port_type == PORT_TYPE_MIDI_ALSA)
        pen = QPen(canvas.theme->line_midi_alsa, 2);

    QColor color(0,0,0,0);
    setBrush(color);
    setPen(pen);
    update();
}

void UIGChooserItem::updateGeometry()
{
    /* Call to base-class: */
    QIGraphicsWidget::updateGeometry();

    /* Update parent's geometry: */
    if (parentItem())
        parentItem()->updateGeometry();

    /* Special handling for root-items: */
    if (isRoot())
    {
        /* Root-item should notify chooser-view if minimum-width-hint was changed: */
        int iMinimumWidthHint = minimumWidthHint();
        if (m_iPreviousMinimumWidthHint != iMinimumWidthHint)
        {
            /* Save new minimum-width-hint, notify listener: */
            m_iPreviousMinimumWidthHint = iMinimumWidthHint;
            emit sigMinimumWidthHintChanged(m_iPreviousMinimumWidthHint);
        }
        /* Root-item should notify chooser-view if minimum-height-hint was changed: */
        int iMinimumHeightHint = minimumHeightHint();
        if (m_iPreviousMinimumHeightHint != iMinimumHeightHint)
        {
            /* Save new minimum-height-hint, notify listener: */
            m_iPreviousMinimumHeightHint = iMinimumHeightHint;
            emit sigMinimumHeightHintChanged(m_iPreviousMinimumHeightHint);
        }
    }
}

void QSGParticlePainter::componentComplete()
{
    if (!m_system && qobject_cast<QSGParticleSystem*>(parentItem()))
        setSystem(qobject_cast<QSGParticleSystem*>(parentItem()));
    if (!m_system)
        qWarning() << "ParticlePainter created without a particle system specified";//TODO: useful QML warnings, like line number?
    QSGItem::componentComplete();
}

QRectF HighlightItem::parentRect() const
{
    if (parentItem())
        return parentItem()->boundingRect();
    else if (scene())
        return scene()->sceneRect();
    return QRectF(0, 0, 10, 10);
}

void GEventNode::UpdateVerticalPosition()
{
	// if their is a parent item, we draw the line within the pParentItem->boundingRect(). 
	double heightLine = 11.4159;
	if(parentItem())
		heightLine = parentItem()->boundingRect().height();
	setLine(0.0, 0.0, 0.0, heightLine);
}

UIGSelectorItemGroup::~UIGSelectorItemGroup()
{
    /* Delete all the items: */
    clearItems();

    /* Remove item from the parent: */
    if (parentItem())
        parentItem()->removeItem(this);
}

bool Cell::isGrouped()
{

    if(parentItem()) {
        qDebug() << "isGrouped parent type:" << parentItem()->Type;
        return true;
    }

    return false;
}