qcombobox.cpp

Go to the documentation of this file.

// Copyright (C) 2020 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qcombobox.h"
 
#include <qstylepainter.h>
#include <qpa/qplatformtheme.h>
#include <qpa/qplatformmenu.h>
#include <qlineedit.h>
#include <qapplication.h>
#include <qlistview.h>
#if QT_CONFIG(tableview)
#include <qtableview.h>
#endif
#include <qitemdelegate.h>
#include <qmap.h>
#if QT_CONFIG(menu)
#include <qmenu.h>
#endif
#include <qevent.h>
#include <qlayout.h>
#include <qscrollbar.h>
#if QT_CONFIG(treeview)
#include <qtreeview.h>
#endif
#include <qheaderview.h>
#include <qmath.h>
#include <qmetaobject.h>
#if QT_CONFIG(proxymodel)
#include <qabstractproxymodel.h>
#endif
#include <qstylehints.h>
#include <private/qguiapplication_p.h>
#include <private/qhighdpiscaling_p.h>
#include <private/qapplication_p.h>
#include <private/qcombobox_p.h>
#include <private/qabstractitemmodel_p.h>
#include <private/qabstractscrollarea_p.h>
#include <private/qlineedit_p.h>
#if QT_CONFIG(completer)
#include <private/qcompleter_p.h>
#endif
#include <qdebug.h>
#if QT_CONFIG(effects)
# include <private/qeffects_p.h>
#endif
#include <private/qstyle_p.h>
#if QT_CONFIG(accessibility)
#include "qaccessible.h"
#endif
 
QT_BEGIN_NAMESPACE
 
using namespace Qt::StringLiterals;
 
QComboBoxPrivate::QComboBoxPrivate()
    : QWidgetPrivate(),
      shownOnce(false),
      duplicatesEnabled(false),
      frame(true),
      inserting(false),
      hidingPopup(false)
{
}
 
QComboBoxPrivate::~QComboBoxPrivate()
{
#ifdef Q_OS_MAC
    cleanupNativePopup();
#endif
}
 
QStyleOptionMenuItem QComboMenuDelegate::getStyleOption(const QStyleOptionViewItem &option,
                                                        const QModelIndex &index) const
{
    QStyleOptionMenuItem menuOption;
 
    QPalette resolvedpalette = option.palette.resolve(QApplication::palette("QMenu"));
    QVariant value = index.data(Qt::ForegroundRole);
    if (value.canConvert<QBrush>()) {
        resolvedpalette.setBrush(QPalette::WindowText, qvariant_cast<QBrush>(value));
        resolvedpalette.setBrush(QPalette::ButtonText, qvariant_cast<QBrush>(value));
        resolvedpalette.setBrush(QPalette::Text, qvariant_cast<QBrush>(value));
    }
    menuOption.palette = resolvedpalette;
    menuOption.state = QStyle::State_None;
    if (mCombo->window()->isActiveWindow())
        menuOption.state = QStyle::State_Active;
    if ((option.state & QStyle::State_Enabled) && (index.model()->flags(index) & Qt::ItemIsEnabled))
        menuOption.state |= QStyle::State_Enabled;
    else
        menuOption.palette.setCurrentColorGroup(QPalette::Disabled);
    if (option.state & QStyle::State_Selected)
        menuOption.state |= QStyle::State_Selected;
    menuOption.checkType = QStyleOptionMenuItem::NonExclusive;
    // a valid checkstate means that the model has checkable items
    const QVariant checkState = index.data(Qt::CheckStateRole);
    if (!checkState.isValid()) {
        menuOption.checked = mCombo->currentIndex() == index.row();
    } else {
        menuOption.checked = qvariant_cast<int>(checkState) == Qt::Checked;
        menuOption.state |= qvariant_cast<int>(checkState) == Qt::Checked
                          ? QStyle::State_On : QStyle::State_Off;
    }
    if (QComboBoxDelegate::isSeparator(index))
        menuOption.menuItemType = QStyleOptionMenuItem::Separator;
    else
        menuOption.menuItemType = QStyleOptionMenuItem::Normal;
 
    QVariant variant = index.model()->data(index, Qt::DecorationRole);
    switch (variant.userType()) {
    case QMetaType::QIcon:
        menuOption.icon = qvariant_cast<QIcon>(variant);
        break;
    case QMetaType::QColor: {
        static QPixmap pixmap(option.decorationSize);
        pixmap.fill(qvariant_cast<QColor>(variant));
        menuOption.icon = pixmap;
        break; }
    default:
        menuOption.icon = qvariant_cast<QPixmap>(variant);
        break;
    }
    if (index.data(Qt::BackgroundRole).canConvert<QBrush>()) {
        menuOption.palette.setBrush(QPalette::All, QPalette::Window,
                                    qvariant_cast<QBrush>(index.data(Qt::BackgroundRole)));
    }
    menuOption.text = index.model()->data(index, Qt::DisplayRole).toString().replace(u'&', "&&"_L1);
    menuOption.reservedShortcutWidth = 0;
    menuOption.maxIconWidth =  option.decorationSize.width() + 4;
    menuOption.menuRect = option.rect;
    menuOption.rect = option.rect;
 
    // Make sure fonts set on the model or on the combo box, in
    // that order, also override the font for the popup menu.
    QVariant fontRoleData = index.data(Qt::FontRole);
    if (fontRoleData.isValid()) {
        menuOption.font = qvariant_cast<QFont>(fontRoleData);
    } else if (mCombo->testAttribute(Qt::WA_SetFont)
            || mCombo->testAttribute(Qt::WA_MacSmallSize)
            || mCombo->testAttribute(Qt::WA_MacMiniSize)
            || mCombo->font() != qt_app_fonts_hash()->value("QComboBox", QFont())) {
        menuOption.font = mCombo->font();
    } else {
        menuOption.font = qt_app_fonts_hash()->value("QComboMenuItem", mCombo->font());
    }
 
    menuOption.fontMetrics = QFontMetrics(menuOption.font);
 
    return menuOption;
}
 
bool QComboMenuDelegate::editorEvent(QEvent *event, QAbstractItemModel *model,
                                     const QStyleOptionViewItem &option, const QModelIndex &index)
{
    Q_ASSERT(event);
    Q_ASSERT(model);
 
    // make sure that the item is checkable
    Qt::ItemFlags flags = model->flags(index);
    if (!(flags & Qt::ItemIsUserCheckable) || !(option.state & QStyle::State_Enabled)
        || !(flags & Qt::ItemIsEnabled))
        return false;
 
    // make sure that we have a check state
    const QVariant checkState = index.data(Qt::CheckStateRole);
    if (!checkState.isValid())
        return false;
 
    // make sure that we have the right event type
    if ((event->type() == QEvent::MouseButtonRelease)
        || (event->type() == QEvent::MouseButtonDblClick)
        || (event->type() == QEvent::MouseButtonPress)) {
        QMouseEvent *me = static_cast<QMouseEvent*>(event);
        if (me->button() != Qt::LeftButton)
            return false;
 
        if ((event->type() == QEvent::MouseButtonPress)
            || (event->type() == QEvent::MouseButtonDblClick)) {
            pressedIndex = index.row();
            return false;
        }
 
        if (index.row() != pressedIndex)
            return false;
        pressedIndex = -1;
 
    } else if (event->type() == QEvent::KeyPress) {
        if (static_cast<QKeyEvent*>(event)->key() != Qt::Key_Space
         && static_cast<QKeyEvent*>(event)->key() != Qt::Key_Select)
            return false;
    } else {
        return false;
    }
 
    // we don't support user-tristate items in QComboBox (not implemented in any style)
    Qt::CheckState newState = (static_cast<Qt::CheckState>(checkState.toInt()) == Qt::Checked)
                            ? Qt::Unchecked : Qt::Checked;
    return model->setData(index, newState, Qt::CheckStateRole);
}
 
#if QT_CONFIG(completer)
void QComboBoxPrivate::_q_completerActivated(const QModelIndex &index)
{
    Q_Q(QComboBox);
#if QT_CONFIG(proxymodel)
    if (index.isValid() && q->completer()) {
        QAbstractProxyModel *proxy = qobject_cast<QAbstractProxyModel *>(q->completer()->completionModel());
        if (proxy) {
            const QModelIndex &completerIndex = proxy->mapToSource(index);
            int row = -1;
            if (completerIndex.model() == model) {
                row = completerIndex.row();
            } else {
                // if QCompleter uses a proxy model to host widget's one - map again
                QAbstractProxyModel *completerProxy = qobject_cast<QAbstractProxyModel *>(q->completer()->model());
                if (completerProxy && completerProxy->sourceModel() == model) {
                    row = completerProxy->mapToSource(completerIndex).row();
                } else {
                    QString match = q->completer()->model()->data(completerIndex).toString();
                    row = q->findText(match, matchFlags());
                }
            }
            q->setCurrentIndex(row);
            emitActivated(currentIndex);
        }
    }
#endif
}
#endif // QT_CONFIG(completer)
 
void QComboBoxPrivate::updateArrow(QStyle::StateFlag state)
{
    Q_Q(QComboBox);
    if (arrowState == state)
        return;
    arrowState = state;
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    q->update(q->rect());
}
 
void QComboBoxPrivate::_q_modelReset()
{
    Q_Q(QComboBox);
    if (lineEdit) {
        lineEdit->setText(QString());
        updateLineEditGeometry();
    }
    trySetValidIndex();
    modelChanged();
    q->update();
}
 
void QComboBoxPrivate::_q_modelDestroyed()
{
    model = QAbstractItemModelPrivate::staticEmptyModel();
}
 
void QComboBoxPrivate::trySetValidIndex()
{
    Q_Q(QComboBox);
    bool currentReset = false;
 
    const int rowCount = q->count();
    for (int pos = 0; pos < rowCount; ++pos) {
        const QModelIndex idx(model->index(pos, modelColumn, root));
        if (idx.flags() & Qt::ItemIsEnabled) {
            setCurrentIndex(idx);
            currentReset = true;
            break;
        }
    }
 
    if (!currentReset)
        setCurrentIndex(QModelIndex());
}
 
QRect QComboBoxPrivate::popupGeometry(const QPoint &globalPosition) const
{
    Q_Q(const QComboBox);
    return QStylePrivate::useFullScreenForPopup()
        ? QWidgetPrivate::screenGeometry(q, globalPosition)
        : QWidgetPrivate::availableScreenGeometry(q, globalPosition);
}
 
bool QComboBoxPrivate::updateHoverControl(const QPoint &pos)
{
 
    Q_Q(QComboBox);
    QRect lastHoverRect = hoverRect;
    QStyle::SubControl lastHoverControl = hoverControl;
    bool doesHover = q->testAttribute(Qt::WA_Hover);
    if (lastHoverControl != newHoverControl(pos) && doesHover) {
        q->update(lastHoverRect);
        q->update(hoverRect);
        return true;
    }
    return !doesHover;
}
 
QStyle::SubControl QComboBoxPrivate::newHoverControl(const QPoint &pos)
{
    Q_Q(QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    opt.subControls = QStyle::SC_All;
    hoverControl = q->style()->hitTestComplexControl(QStyle::CC_ComboBox, &opt, pos, q);
    hoverRect = (hoverControl != QStyle::SC_None)
                   ? q->style()->subControlRect(QStyle::CC_ComboBox, &opt, hoverControl, q)
                   : QRect();
    return hoverControl;
}
 
/*
    Computes a size hint based on the maximum width
    for the items in the combobox.
*/
int QComboBoxPrivate::computeWidthHint() const
{
    Q_Q(const QComboBox);
 
    int width = 0;
    const int count = q->count();
    const int iconWidth = q->iconSize().width() + 4;
    const QFontMetrics &fontMetrics = q->fontMetrics();
 
    for (int i = 0; i < count; ++i) {
        const int textWidth = fontMetrics.horizontalAdvance(q->itemText(i));
        if (q->itemIcon(i).isNull())
            width = (qMax(width, textWidth));
        else
            width = (qMax(width, textWidth + iconWidth));
    }
 
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    QSize tmp(width, 0);
    tmp = q->style()->sizeFromContents(QStyle::CT_ComboBox, &opt, tmp, q);
    return tmp.width();
}
 
QSize QComboBoxPrivate::recomputeSizeHint(QSize &sh) const
{
    Q_Q(const QComboBox);
    if (!sh.isValid()) {
        bool hasIcon = sizeAdjustPolicy == QComboBox::AdjustToMinimumContentsLengthWithIcon;
        int count = q->count();
        QSize iconSize = q->iconSize();
        const QFontMetrics &fm = q->fontMetrics();
 
        // text width
        if (&sh == &sizeHint || minimumContentsLength == 0) {
            switch (sizeAdjustPolicy) {
            case QComboBox::AdjustToContents:
            case QComboBox::AdjustToContentsOnFirstShow:
                if (count == 0) {
                    sh.rwidth() = 7 * fm.horizontalAdvance(u'x');
                } else {
                    for (int i = 0; i < count; ++i) {
                        if (!q->itemIcon(i).isNull()) {
                            hasIcon = true;
                            sh.setWidth(qMax(sh.width(), fm.boundingRect(q->itemText(i)).width() + iconSize.width() + 4));
                        } else {
                            sh.setWidth(qMax(sh.width(), fm.boundingRect(q->itemText(i)).width()));
                        }
                    }
                }
                break;
            case QComboBox::AdjustToMinimumContentsLengthWithIcon:
                ;
            }
        } else {
            for (int i = 0; i < count && !hasIcon; ++i)
                hasIcon = !q->itemIcon(i).isNull();
        }
        if (minimumContentsLength > 0)
            sh.setWidth(qMax(sh.width(), minimumContentsLength * fm.horizontalAdvance(u'X') + (hasIcon ? iconSize.width() + 4 : 0)));
        if (!placeholderText.isEmpty())
            sh.setWidth(qMax(sh.width(), fm.boundingRect(placeholderText).width()));
 
 
        // height
        sh.setHeight(qMax(qCeil(QFontMetricsF(fm).height()), 14) + 2);
        if (hasIcon) {
            sh.setHeight(qMax(sh.height(), iconSize.height() + 2));
        }
 
        // add style and strut values
        QStyleOptionComboBox opt;
        q->initStyleOption(&opt);
        sh = q->style()->sizeFromContents(QStyle::CT_ComboBox, &opt, sh, q);
    }
    return sh;
}
 
void QComboBoxPrivate::adjustComboBoxSize()
{
    viewContainer()->adjustSizeTimer.start(20, container);
}
 
void QComboBoxPrivate::updateLayoutDirection()
{
    Q_Q(const QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    Qt::LayoutDirection dir = Qt::LayoutDirection(
        q->style()->styleHint(QStyle::SH_ComboBox_LayoutDirection, &opt, q));
    if (lineEdit)
        lineEdit->setLayoutDirection(dir);
    if (container)
        container->setLayoutDirection(dir);
}
 
 
void QComboBoxPrivateContainer::timerEvent(QTimerEvent *timerEvent)
{
    if (timerEvent->timerId() == adjustSizeTimer.timerId()) {
        adjustSizeTimer.stop();
        if (combo->sizeAdjustPolicy() == QComboBox::AdjustToContents) {
            combo->updateGeometry();
            combo->adjustSize();
            combo->update();
        }
    }
}
 
void QComboBoxPrivateContainer::resizeEvent(QResizeEvent *e)
{
    QStyleOptionComboBox opt = comboStyleOption();
    if (combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo)) {
        QStyleOption myOpt;
        myOpt.initFrom(this);
        QStyleHintReturnMask mask;
        if (combo->style()->styleHint(QStyle::SH_Menu_Mask, &myOpt, this, &mask)) {
            setMask(mask.region);
        }
    } else {
        clearMask();
    }
    QFrame::resizeEvent(e);
}
 
void QComboBoxPrivateContainer::paintEvent(QPaintEvent *e)
{
    QStyleOptionComboBox cbOpt = comboStyleOption();
    if (combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &cbOpt, combo)
            && mask().isEmpty()) {
        QStyleOption opt;
        opt.initFrom(this);
        QPainter p(this);
        style()->drawPrimitive(QStyle::PE_PanelMenu, &opt, &p, this);
    }
 
    QFrame::paintEvent(e);
}
 
QComboBoxPrivateContainer::QComboBoxPrivateContainer(QAbstractItemView *itemView, QComboBox *parent)
    : QFrame(parent, Qt::Popup), combo(parent)
{
    // we need the combobox and itemview
    Q_ASSERT(parent);
    Q_ASSERT(itemView);
 
    setAttribute(Qt::WA_WindowPropagation);
    setAttribute(Qt::WA_X11NetWmWindowTypeCombo);
 
    // setup container
    blockMouseReleaseTimer.setSingleShot(true);
 
    // we need a vertical layout
    QBoxLayout *layout =  new QBoxLayout(QBoxLayout::TopToBottom, this);
    layout->setSpacing(0);
    layout->setContentsMargins(QMargins());
 
    // set item view
    setItemView(itemView);
 
    // add scroller arrows if style needs them
    QStyleOptionComboBox opt = comboStyleOption();
    const bool usePopup = combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo);
    if (usePopup) {
        top = new QComboBoxPrivateScroller(QAbstractSlider::SliderSingleStepSub, this);
        bottom = new QComboBoxPrivateScroller(QAbstractSlider::SliderSingleStepAdd, this);
        top->hide();
        bottom->hide();
    } else {
        setLineWidth(1);
    }
 
    if (top) {
        layout->insertWidget(0, top);
        connect(top, SIGNAL(doScroll(int)), this, SLOT(scrollItemView(int)));
    }
    if (bottom) {
        layout->addWidget(bottom);
        connect(bottom, SIGNAL(doScroll(int)), this, SLOT(scrollItemView(int)));
    }
 
    // Some styles (Mac) have a margin at the top and bottom of the popup.
    layout->insertSpacing(0, 0);
    layout->addSpacing(0);
    updateStyleSettings();
}
 
void QComboBoxPrivateContainer::scrollItemView(int action)
{
#if QT_CONFIG(scrollbar)
    if (view->verticalScrollBar())
        view->verticalScrollBar()->triggerAction(static_cast<QAbstractSlider::SliderAction>(action));
#endif
}
 
void QComboBoxPrivateContainer::hideScrollers()
{
    if (top)
        top->hide();
    if (bottom)
        bottom->hide();
}
 
/*
    Hides or shows the scrollers when we emulate a popupmenu
*/
void QComboBoxPrivateContainer::updateScrollers()
{
#if QT_CONFIG(scrollbar)
    if (!top || !bottom)
        return;
 
    if (isVisible() == false)
        return;
 
    QStyleOptionComboBox opt = comboStyleOption();
    if (combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo) &&
        view->verticalScrollBar()->minimum() < view->verticalScrollBar()->maximum()) {
 
        bool needTop = view->verticalScrollBar()->value()
                       > (view->verticalScrollBar()->minimum() + topMargin());
        bool needBottom = view->verticalScrollBar()->value()
                          < (view->verticalScrollBar()->maximum() - bottomMargin() - topMargin());
        if (needTop)
            top->show();
        else
            top->hide();
        if (needBottom)
            bottom->show();
        else
            bottom->hide();
    } else {
        top->hide();
        bottom->hide();
    }
#endif // QT_CONFIG(scrollbar)
}
 
/*
    Cleans up when the view is destroyed.
*/
void QComboBoxPrivateContainer::viewDestroyed()
{
    view = nullptr;
    setItemView(new QComboBoxListView());
}
 
/*
    Returns the item view used for the combobox popup.
*/
QAbstractItemView *QComboBoxPrivateContainer::itemView() const
{
    return view;
}
 
void QComboBoxPrivateContainer::setItemView(QAbstractItemView *itemView)
{
    Q_ASSERT(itemView);
 
    // clean up old one
    if (view) {
        view->removeEventFilter(this);
        view->viewport()->removeEventFilter(this);
#if QT_CONFIG(scrollbar)
        disconnect(view->verticalScrollBar(), SIGNAL(valueChanged(int)),
                   this, SLOT(updateScrollers()));
        disconnect(view->verticalScrollBar(), SIGNAL(rangeChanged(int,int)),
                   this, SLOT(updateScrollers()));
#endif
        disconnect(view, SIGNAL(destroyed()),
                   this, SLOT(viewDestroyed()));
 
        if (isAncestorOf(view))
            delete view;
        view = nullptr;
    }
 
    // setup the item view
    view = itemView;
    view->setParent(this);
    view->setAttribute(Qt::WA_MacShowFocusRect, false);
    qobject_cast<QBoxLayout*>(layout())->insertWidget(top ? 2 : 0, view);
    view->setSizePolicy(QSizePolicy::Ignored, QSizePolicy::Ignored);
    view->installEventFilter(this);
    view->viewport()->installEventFilter(this);
    view->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
    QStyleOptionComboBox opt = comboStyleOption();
    const bool usePopup = combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo);
#if QT_CONFIG(scrollbar)
    if (usePopup)
        view->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
#endif
    if (combo->style()->styleHint(QStyle::SH_ComboBox_ListMouseTracking, &opt, combo) ||
        usePopup) {
        view->setMouseTracking(true);
    }
    view->setSelectionMode(QAbstractItemView::SingleSelection);
    view->setFrameStyle(QFrame::NoFrame);
    view->setLineWidth(0);
    view->setEditTriggers(QAbstractItemView::NoEditTriggers);
#if QT_CONFIG(scrollbar)
    connect(view->verticalScrollBar(), SIGNAL(valueChanged(int)),
            this, SLOT(updateScrollers()));
    connect(view->verticalScrollBar(), SIGNAL(rangeChanged(int,int)),
            this, SLOT(updateScrollers()));
#endif
    connect(view, SIGNAL(destroyed()),
            this, SLOT(viewDestroyed()));
}
 
int QComboBoxPrivateContainer::topMargin() const
{
    if (const QListView *lview = qobject_cast<const QListView*>(view))
        return lview->spacing();
#if QT_CONFIG(tableview)
    if (const QTableView *tview = qobject_cast<const QTableView*>(view))
        return tview->showGrid() ? 1 : 0;
#endif
    return 0;
}
 
int QComboBoxPrivateContainer::spacing() const
{
    QListView *lview = qobject_cast<QListView*>(view);
    if (lview)
        return 2 * lview->spacing(); // QListView::spacing is the padding around the item.
#if QT_CONFIG(tableview)
    QTableView *tview = qobject_cast<QTableView*>(view);
    if (tview)
        return tview->showGrid() ? 1 : 0;
#endif
    return 0;
}
 
void QComboBoxPrivateContainer::updateTopBottomMargin()
{
    if (!layout() || layout()->count() < 1)
        return;
 
    QBoxLayout *boxLayout = qobject_cast<QBoxLayout *>(layout());
    if (!boxLayout)
        return;
 
    const QStyleOptionComboBox opt = comboStyleOption();
    const bool usePopup = combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo);
    const int margin = usePopup ? combo->style()->pixelMetric(QStyle::PM_MenuVMargin, &opt, combo) : 0;
 
    QSpacerItem *topSpacer = boxLayout->itemAt(0)->spacerItem();
    if (topSpacer)
        topSpacer->changeSize(0, margin, QSizePolicy::Minimum, QSizePolicy::Fixed);
 
    QSpacerItem *bottomSpacer = boxLayout->itemAt(boxLayout->count() - 1)->spacerItem();
    if (bottomSpacer && bottomSpacer != topSpacer)
        bottomSpacer->changeSize(0, margin, QSizePolicy::Minimum, QSizePolicy::Fixed);
 
    boxLayout->invalidate();
}
 
void QComboBoxPrivateContainer::updateStyleSettings()
{
    // add scroller arrows if style needs them
    QStyleOptionComboBox opt = comboStyleOption();
    view->setMouseTracking(combo->style()->styleHint(QStyle::SH_ComboBox_ListMouseTracking, &opt, combo) ||
                           combo->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, combo));
    setFrameStyle(combo->style()->styleHint(QStyle::SH_ComboBox_PopupFrameStyle, &opt, combo));
    updateTopBottomMargin();
}
 
void QComboBoxPrivateContainer::changeEvent(QEvent *e)
{
    if (e->type() == QEvent::StyleChange)
        updateStyleSettings();
 
    QFrame::changeEvent(e);
}
 
 
bool QComboBoxPrivateContainer::eventFilter(QObject *o, QEvent *e)
{
    switch (e->type()) {
    case QEvent::ShortcutOverride: {
        QKeyEvent *keyEvent = static_cast<QKeyEvent*>(e);
        switch (keyEvent->key()) {
        case Qt::Key_Enter:
        case Qt::Key_Return:
#ifdef QT_KEYPAD_NAVIGATION
        case Qt::Key_Select:
#endif
            if (view->currentIndex().isValid() && view->currentIndex().flags().testFlag(Qt::ItemIsEnabled)) {
                combo->hidePopup();
                emit itemSelected(view->currentIndex());
            }
            return true;
        case Qt::Key_Down:
            if (!(keyEvent->modifiers() & Qt::AltModifier))
                break;
            Q_FALLTHROUGH();
        case Qt::Key_F4:
            combo->hidePopup();
            return true;
        default:
#if QT_CONFIG(shortcut)
            if (keyEvent->matches(QKeySequence::Cancel) && isVisible()) {
                keyEvent->accept();
                return true;
            }
#endif
            break;
        }
        break;
    }
    case QEvent::MouseMove:
        if (isVisible()) {
            QMouseEvent *m = static_cast<QMouseEvent *>(e);
            QWidget *widget = static_cast<QWidget *>(o);
            QPoint vector = widget->mapToGlobal(m->position().toPoint()) - initialClickPosition;
            if (vector.manhattanLength() > 9 && blockMouseReleaseTimer.isActive())
                blockMouseReleaseTimer.stop();
            QModelIndex indexUnderMouse = view->indexAt(m->position().toPoint());
            if (indexUnderMouse.isValid()
                     && !QComboBoxDelegate::isSeparator(indexUnderMouse)) {
                view->setCurrentIndex(indexUnderMouse);
            }
        }
        break;
    case QEvent::MouseButtonPress:
        maybeIgnoreMouseButtonRelease = false;
        break;
    case QEvent::MouseButtonRelease: {
        bool ignoreEvent = maybeIgnoreMouseButtonRelease && popupTimer.elapsed() < QApplication::doubleClickInterval();
 
        QMouseEvent *m = static_cast<QMouseEvent *>(e);
        if (isVisible() && view->rect().contains(m->position().toPoint()) && view->currentIndex().isValid()
            && !blockMouseReleaseTimer.isActive() && !ignoreEvent
            && (view->currentIndex().flags().testFlag(Qt::ItemIsEnabled))
            && (view->currentIndex().flags().testFlag(Qt::ItemIsSelectable))) {
            combo->hidePopup();
            emit itemSelected(view->currentIndex());
            return true;
        }
        break;
    }
    default:
        break;
    }
    return QFrame::eventFilter(o, e);
}
 
void QComboBoxPrivateContainer::showEvent(QShowEvent *)
{
    combo->update();
}
 
void QComboBoxPrivateContainer::hideEvent(QHideEvent *)
{
    emit resetButton();
    combo->update();
#if QT_CONFIG(graphicsview)
    // QGraphicsScenePrivate::removePopup closes the combo box popup, it hides it non-explicitly.
    // Hiding/showing the QComboBox after this will unexpectedly show the popup as well.
    // Re-hiding the popup container makes sure it is explicitly hidden.
    if (QGraphicsProxyWidget *proxy = graphicsProxyWidget())
        proxy->hide();
#endif
}
 
void QComboBoxPrivateContainer::mousePressEvent(QMouseEvent *e)
{
 
    QStyleOptionComboBox opt = comboStyleOption();
    opt.subControls = QStyle::SC_All;
    opt.activeSubControls = QStyle::SC_ComboBoxArrow;
    QStyle::SubControl sc = combo->style()->hitTestComplexControl(QStyle::CC_ComboBox, &opt,
                                                           combo->mapFromGlobal(e->globalPosition().toPoint()),
                                                           combo);
    if ((combo->isEditable() && sc == QStyle::SC_ComboBoxArrow)
        || (!combo->isEditable() && sc != QStyle::SC_None))
        setAttribute(Qt::WA_NoMouseReplay);
    combo->hidePopup();
}
 
void QComboBoxPrivateContainer::mouseReleaseEvent(QMouseEvent *e)
{
    Q_UNUSED(e);
    if (!blockMouseReleaseTimer.isActive()) {
        combo->hidePopup();
        emit resetButton();
    }
}
 
QStyleOptionComboBox QComboBoxPrivateContainer::comboStyleOption() const
{
    // ### This should use QComboBox's initStyleOption(), but it's protected
    // perhaps, we could cheat by having the QCombo private instead?
    QStyleOptionComboBox opt;
    opt.initFrom(combo);
    opt.subControls = QStyle::SC_All;
    opt.activeSubControls = QStyle::SC_None;
    opt.editable = combo->isEditable();
    return opt;
}
 
QComboBox::QComboBox(QWidget *parent)
    : QWidget(*new QComboBoxPrivate(), parent, { })
{
    Q_D(QComboBox);
    d->init();
}
 
QComboBox::QComboBox(QComboBoxPrivate &dd, QWidget *parent)
    : QWidget(dd, parent, { })
{
    Q_D(QComboBox);
    d->init();
}
 
void QComboBoxPrivate::init()
{
    Q_Q(QComboBox);
#ifdef Q_OS_MACOS
    // On OS X, only line edits and list views always get tab focus. It's only
    // when we enable full keyboard access that other controls can get tab focus.
    // When it's not editable, a combobox looks like a button, and it behaves as
    // such in this respect.
    if (!q->isEditable())
        q->setFocusPolicy(Qt::TabFocus);
    else
#endif
        q->setFocusPolicy(Qt::WheelFocus);
 
    q->setSizePolicy(QSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed,
                                 QSizePolicy::ComboBox));
    setLayoutItemMargins(QStyle::SE_ComboBoxLayoutItem);
    q->setModel(new QStandardItemModel(0, 1, q));
    if (!q->isEditable())
        q->setAttribute(Qt::WA_InputMethodEnabled, false);
    else
        q->setAttribute(Qt::WA_InputMethodEnabled);
}
 
QComboBoxPrivateContainer* QComboBoxPrivate::viewContainer()
{
    if (container)
        return container;
 
    Q_Q(QComboBox);
    container = new QComboBoxPrivateContainer(new QComboBoxListView(q), q);
    container->itemView()->setModel(model);
    container->itemView()->setTextElideMode(Qt::ElideMiddle);
    updateDelegate(true);
    updateLayoutDirection();
    updateViewContainerPaletteAndOpacity();
    QObject::connect(container, SIGNAL(itemSelected(QModelIndex)),
                     q, SLOT(_q_itemSelected(QModelIndex)));
    QObject::connect(container->itemView()->selectionModel(),
                     SIGNAL(currentChanged(QModelIndex,QModelIndex)),
                     q, SLOT(_q_emitHighlighted(QModelIndex)));
    QObject::connect(container, SIGNAL(resetButton()), q, SLOT(_q_resetButton()));
    return container;
}
 
 
void QComboBoxPrivate::_q_resetButton()
{
    updateArrow(QStyle::State_None);
}
 
void QComboBoxPrivate::_q_dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
{
    Q_Q(QComboBox);
    if (inserting || topLeft.parent() != root)
        return;
 
    if (sizeAdjustPolicy == QComboBox::AdjustToContents) {
        sizeHint = QSize();
        adjustComboBoxSize();
        q->updateGeometry();
    }
 
    if (currentIndex.row() >= topLeft.row() && currentIndex.row() <= bottomRight.row()) {
        const QString text = q->itemText(currentIndex.row());
        if (lineEdit) {
            lineEdit->setText(text);
            updateLineEditGeometry();
        } else {
            updateCurrentText(text);
        }
        q->update();
#if QT_CONFIG(accessibility)
        QAccessibleValueChangeEvent event(q, text);
        QAccessible::updateAccessibility(&event);
#endif
    }
}
 
void QComboBoxPrivate::_q_rowsInserted(const QModelIndex &parent, int start, int end)
{
    Q_Q(QComboBox);
    if (inserting || parent != root)
        return;
 
    if (sizeAdjustPolicy == QComboBox::AdjustToContents) {
        sizeHint = QSize();
        adjustComboBoxSize();
        q->updateGeometry();
    }
 
    // set current index if combo was previously empty and there is no placeholderText
    if (start == 0 && (end - start + 1) == q->count() && !currentIndex.isValid() &&
        placeholderText.isEmpty()) {
        q->setCurrentIndex(0);
        // need to emit changed if model updated index "silently"
    } else if (currentIndex.row() != indexBeforeChange) {
        q->update();
        _q_emitCurrentIndexChanged(currentIndex);
    }
}
 
void QComboBoxPrivate::_q_updateIndexBeforeChange()
{
    indexBeforeChange = currentIndex.row();
}
 
void QComboBoxPrivate::_q_rowsRemoved(const QModelIndex &parent, int /*start*/, int /*end*/)
{
    Q_Q(QComboBox);
    if (parent != root)
        return;
 
    if (sizeAdjustPolicy == QComboBox::AdjustToContents) {
        sizeHint = QSize();
        adjustComboBoxSize();
        q->updateGeometry();
    }
 
    // model has removed the last row
    if (model->rowCount(root) == 0) {
        setCurrentIndex(QModelIndex());
        return;
    }
 
    // model has changed the currentIndex
    if (currentIndex.row() != indexBeforeChange) {
        if (!currentIndex.isValid() && q->count()) {
            q->setCurrentIndex(qMin(q->count() - 1, qMax(indexBeforeChange, 0)));
            return;
        }
        if (lineEdit) {
            lineEdit->setText(q->itemText(currentIndex.row()));
            updateLineEditGeometry();
        }
        q->update();
        _q_emitCurrentIndexChanged(currentIndex);
    }
}
 
 
void QComboBoxPrivate::updateViewContainerPaletteAndOpacity()
{
    if (!container)
        return;
    Q_Q(QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
#if QT_CONFIG(menu)
    if (q->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, q)) {
        QMenu menu;
        menu.ensurePolished();
        container->setPalette(menu.palette());
        container->setWindowOpacity(menu.windowOpacity());
    } else
#endif
    {
        container->setPalette(q->palette());
        container->setWindowOpacity(1.0);
    }
    if (lineEdit)
        lineEdit->setPalette(q->palette());
}
 
void QComboBoxPrivate::updateFocusPolicy()
{
#ifdef Q_OS_MACOS
    Q_Q(QComboBox);
 
    // See comment in QComboBoxPrivate::init()
    if (q->isEditable())
        q->setFocusPolicy(Qt::WheelFocus);
    else
        q->setFocusPolicy(Qt::TabFocus);
#endif
}
 
void QComboBox::initStyleOption(QStyleOptionComboBox *option) const
{
    if (!option)
        return;
 
    Q_D(const QComboBox);
    option->initFrom(this);
    option->editable = isEditable();
    option->frame = d->frame;
    if (hasFocus() && !option->editable)
        option->state |= QStyle::State_Selected;
    option->subControls = QStyle::SC_All;
    if (d->arrowState == QStyle::State_Sunken) {
        option->activeSubControls = QStyle::SC_ComboBoxArrow;
        option->state |= d->arrowState;
    } else {
        option->activeSubControls = d->hoverControl;
    }
    option->currentText = currentText();
    if (d->currentIndex.isValid()) {
        option->currentIcon = d->itemIcon(d->currentIndex);
        QVariant alignment = d->model->data(d->currentIndex, Qt::TextAlignmentRole);
        if (alignment.isValid())
            option->textAlignment = static_cast<Qt::Alignment>(alignment.toUInt());
    }
    option->iconSize = iconSize();
    if (d->container && d->container->isVisible())
        option->state |= QStyle::State_On;
}
 
void QComboBoxPrivate::updateLineEditGeometry()
{
    if (!lineEdit)
        return;
 
    Q_Q(QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    QRect editRect = q->style()->subControlRect(QStyle::CC_ComboBox, &opt,
                                                QStyle::SC_ComboBoxEditField, q);
    if (!q->itemIcon(q->currentIndex()).isNull()) {
        QRect comboRect(editRect);
        editRect.setWidth(editRect.width() - q->iconSize().width() - 4);
        editRect = QStyle::alignedRect(q->layoutDirection(), Qt::AlignRight,
                                       editRect.size(), comboRect);
    }
    lineEdit->setGeometry(editRect);
}
 
Qt::MatchFlags QComboBoxPrivate::matchFlags() const
{
    // Base how duplicates are determined on the autocompletion case sensitivity
    Qt::MatchFlags flags = Qt::MatchFixedString;
#if QT_CONFIG(completer)
    if (!lineEdit->completer() || lineEdit->completer()->caseSensitivity() == Qt::CaseSensitive)
#endif
        flags |= Qt::MatchCaseSensitive;
    return flags;
}
 
 
void QComboBoxPrivate::_q_editingFinished()
{
    Q_Q(QComboBox);
    if (!lineEdit)
        return;
    const auto leText = lineEdit->text();
    if (!leText.isEmpty() && itemText(currentIndex) != leText) {
#if QT_CONFIG(completer)
        const auto *leCompleter = lineEdit->completer();
        const auto *popup = leCompleter ? QCompleterPrivate::get(leCompleter)->popup : nullptr;
        if (popup && popup->isVisible()) {
            // QLineEdit::editingFinished() will be emitted before the code flow returns
            // to QCompleter::eventFilter(), where QCompleter::activated() may be emitted.
            // We know that the completer popup will still be visible at this point, and
            // that any selection should be valid.
            const QItemSelectionModel *selModel = popup->selectionModel();
            const QModelIndex curIndex = popup->currentIndex();
            const bool completerIsActive = selModel && selModel->selectedIndexes().contains(curIndex);
 
            if (completerIsActive)
                return;
        }
#endif
        const int index = q_func()->findText(leText, matchFlags());
        if (index != -1) {
            q->setCurrentIndex(index);
            emitActivated(currentIndex);
        }
    }
 
}
 
void QComboBoxPrivate::_q_returnPressed()
{
    Q_Q(QComboBox);
 
    // The insertion code below does not apply when the policy is QComboBox::NoInsert.
    // In case a completer is installed, item activation via the completer is handled
    // in _q_completerActivated(). Otherwise _q_editingFinished() updates the current
    // index as appropriate.
    if (insertPolicy == QComboBox::NoInsert)
        return;
 
    if (lineEdit && !lineEdit->text().isEmpty()) {
        if (q->count() >= maxCount && !(this->insertPolicy == QComboBox::InsertAtCurrent))
            return;
        lineEdit->deselect();
        lineEdit->end(false);
        QString text = lineEdit->text();
        // check for duplicates (if not enabled) and quit
        int index = -1;
        if (!duplicatesEnabled) {
            index = q->findText(text, matchFlags());
            if (index != -1) {
                q->setCurrentIndex(index);
                emitActivated(currentIndex);
                return;
            }
        }
        switch (insertPolicy) {
        case QComboBox::InsertAtTop:
            index = 0;
            break;
        case QComboBox::InsertAtBottom:
            index = q->count();
            break;
        case QComboBox::InsertAtCurrent:
        case QComboBox::InsertAfterCurrent:
        case QComboBox::InsertBeforeCurrent:
            if (!q->count() || !currentIndex.isValid())
                index = 0;
            else if (insertPolicy == QComboBox::InsertAtCurrent)
                q->setItemText(q->currentIndex(), text);
            else if (insertPolicy == QComboBox::InsertAfterCurrent)
                index = q->currentIndex() + 1;
            else if (insertPolicy == QComboBox::InsertBeforeCurrent)
                index = q->currentIndex();
            break;
        case QComboBox::InsertAlphabetically:
            index = 0;
            for (int i = 0; i < q->count(); ++i, ++index) {
                if (text.toLower() < q->itemText(i).toLower())
                    break;
            }
            break;
        default:
            break;
        }
        if (index >= 0) {
            q->insertItem(index, text);
            q->setCurrentIndex(index);
            emitActivated(currentIndex);
        }
    }
}
 
void QComboBoxPrivate::_q_itemSelected(const QModelIndex &item)
{
    Q_Q(QComboBox);
    if (item != currentIndex) {
        setCurrentIndex(item);
    } else if (lineEdit) {
        lineEdit->selectAll();
        lineEdit->setText(q->itemText(currentIndex.row()));
    }
    emitActivated(currentIndex);
}
 
void QComboBoxPrivate::emitActivated(const QModelIndex &index)
{
    Q_Q(QComboBox);
    if (!index.isValid())
        return;
    QString text(itemText(index));
    emit q->activated(index.row());
    emit q->textActivated(text);
}
 
void QComboBoxPrivate::_q_emitHighlighted(const QModelIndex &index)
{
    Q_Q(QComboBox);
    if (!index.isValid())
        return;
    QString text(itemText(index));
    emit q->highlighted(index.row());
    emit q->textHighlighted(text);
}
 
void QComboBoxPrivate::_q_emitCurrentIndexChanged(const QModelIndex &index)
{
    Q_Q(QComboBox);
    const QString text = itemText(index);
    emit q->currentIndexChanged(index.row());
    // signal lineEdit.textChanged already connected to signal currentTextChanged, so don't emit double here
    if (!lineEdit)
        updateCurrentText(text);
#if QT_CONFIG(accessibility)
    QAccessibleValueChangeEvent event(q, text);
    QAccessible::updateAccessibility(&event);
#endif
}
 
QString QComboBoxPrivate::itemText(const QModelIndex &index) const
{
    return index.isValid() ? model->data(index, itemRole()).toString() : QString();
}
 
int QComboBoxPrivate::itemRole() const
{
    return q_func()->isEditable() ? Qt::EditRole : Qt::DisplayRole;
}
 
QComboBox::~QComboBox()
{
    // ### check delegateparent and delete delegate if us?
    Q_D(QComboBox);
 
    QT_TRY {
        disconnect(d->model, SIGNAL(destroyed()),
                this, SLOT(_q_modelDestroyed()));
    } QT_CATCH(...) {
        ; // objects can't throw in destructor
    }
}
 
int QComboBox::maxVisibleItems() const
{
    Q_D(const QComboBox);
    return d->maxVisibleItems;
}
 
void QComboBox::setMaxVisibleItems(int maxItems)
{
    Q_D(QComboBox);
    if (Q_UNLIKELY(maxItems < 0)) {
        qWarning("QComboBox::setMaxVisibleItems: "
                 "Invalid max visible items (%d) must be >= 0", maxItems);
        return;
    }
    d->maxVisibleItems = maxItems;
}
 
int QComboBox::count() const
{
    Q_D(const QComboBox);
    return d->model->rowCount(d->root);
}
 
void QComboBox::setMaxCount(int max)
{
    Q_D(QComboBox);
    if (Q_UNLIKELY(max < 0)) {
        qWarning("QComboBox::setMaxCount: Invalid count (%d) must be >= 0", max);
        return;
    }
 
    const int rowCount = count();
    if (rowCount > max)
        d->model->removeRows(max, rowCount - max, d->root);
 
    d->maxCount = max;
}
 
int QComboBox::maxCount() const
{
    Q_D(const QComboBox);
    return d->maxCount;
}
 
bool QComboBox::duplicatesEnabled() const
{
    Q_D(const QComboBox);
    return d->duplicatesEnabled;
}
 
void QComboBox::setDuplicatesEnabled(bool enable)
{
    Q_D(QComboBox);
    d->duplicatesEnabled = enable;
}
 
int QComboBox::findData(const QVariant &data, int role, Qt::MatchFlags flags) const
{
    Q_D(const QComboBox);
    QModelIndex start = d->model->index(0, d->modelColumn, d->root);
    const QModelIndexList result = d->model->match(start, role, data, 1, flags);
    if (result.isEmpty())
        return -1;
    return result.first().row();
}
 
QComboBox::InsertPolicy QComboBox::insertPolicy() const
{
    Q_D(const QComboBox);
    return d->insertPolicy;
}
 
void QComboBox::setInsertPolicy(InsertPolicy policy)
{
    Q_D(QComboBox);
    d->insertPolicy = policy;
}
 
QComboBox::SizeAdjustPolicy QComboBox::sizeAdjustPolicy() const
{
    Q_D(const QComboBox);
    return d->sizeAdjustPolicy;
}
 
void QComboBox::setSizeAdjustPolicy(QComboBox::SizeAdjustPolicy policy)
{
    Q_D(QComboBox);
    if (policy == d->sizeAdjustPolicy)
        return;
 
    d->sizeAdjustPolicy = policy;
    d->sizeHint = QSize();
    d->adjustComboBoxSize();
    updateGeometry();
}
 
int QComboBox::minimumContentsLength() const
{
    Q_D(const QComboBox);
    return d->minimumContentsLength;
}
 
void QComboBox::setMinimumContentsLength(int characters)
{
    Q_D(QComboBox);
    if (characters == d->minimumContentsLength || characters < 0)
        return;
 
    d->minimumContentsLength = characters;
 
    if (d->sizeAdjustPolicy == AdjustToContents
        || d->sizeAdjustPolicy == AdjustToMinimumContentsLengthWithIcon) {
        d->sizeHint = QSize();
        d->adjustComboBoxSize();
        updateGeometry();
    }
}
 
QSize QComboBox::iconSize() const
{
    Q_D(const QComboBox);
    if (d->iconSize.isValid())
        return d->iconSize;
 
    int iconWidth = style()->pixelMetric(QStyle::PM_SmallIconSize, nullptr, this);
    return QSize(iconWidth, iconWidth);
}
 
void QComboBox::setIconSize(const QSize &size)
{
    Q_D(QComboBox);
    if (size == d->iconSize)
        return;
 
    view()->setIconSize(size);
    d->iconSize = size;
    d->sizeHint = QSize();
    updateGeometry();
}
 
void QComboBox::setPlaceholderText(const QString &placeholderText)
{
    Q_D(QComboBox);
    if (placeholderText == d->placeholderText)
        return;
 
    d->placeholderText = placeholderText;
    if (currentIndex() == -1) {
      if (d->placeholderText.isEmpty())
        setCurrentIndex(0);
      else
        update();
    } else {
      updateGeometry();
    }
}
 
QString QComboBox::placeholderText() const
{
    Q_D(const QComboBox);
    return d->placeholderText;
}
 
bool QComboBox::isEditable() const
{
    Q_D(const QComboBox);
    return d->lineEdit != nullptr;
}
 
void QComboBoxPrivate::updateDelegate(bool force)
{
    Q_Q(QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    if (q->style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, q)) {
        if (force || qobject_cast<QComboBoxDelegate *>(q->itemDelegate()))
            q->setItemDelegate(new QComboMenuDelegate(q->view(), q));
    } else {
        if (force || qobject_cast<QComboMenuDelegate *>(q->itemDelegate()))
            q->setItemDelegate(new QComboBoxDelegate(q->view(), q));
    }
}
 
QIcon QComboBoxPrivate::itemIcon(const QModelIndex &index) const
{
    if (!index.isValid())
        return {};
    QVariant decoration = model->data(index, Qt::DecorationRole);
    if (decoration.userType() == QMetaType::QPixmap)
        return QIcon(qvariant_cast<QPixmap>(decoration));
    else
        return qvariant_cast<QIcon>(decoration);
}
 
void QComboBox::setEditable(bool editable)
{
    Q_D(QComboBox);
    if (isEditable() == editable)
        return;
 
    QStyleOptionComboBox opt;
    initStyleOption(&opt);
    if (editable) {
        if (style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, this)) {
            d->viewContainer()->updateScrollers();
            view()->setVerticalScrollBarPolicy(Qt::ScrollBarAsNeeded);
        }
        QLineEdit *le = new QLineEdit(this);
        le->setPalette(palette());
        setLineEdit(le);
    } else {
        if (style()->styleHint(QStyle::SH_ComboBox_Popup, &opt, this)) {
            d->viewContainer()->updateScrollers();
            view()->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
        }
        setAttribute(Qt::WA_InputMethodEnabled, false);
        d->lineEdit->hide();
        d->lineEdit->deleteLater();
        d->lineEdit = nullptr;
    }
 
    d->updateDelegate();
    d->updateFocusPolicy();
 
    d->viewContainer()->updateTopBottomMargin();
    if (!testAttribute(Qt::WA_Resized))
        adjustSize();
}
 
void QComboBox::setLineEdit(QLineEdit *edit)
{
    Q_D(QComboBox);
    if (Q_UNLIKELY(!edit)) {
        qWarning("QComboBox::setLineEdit: cannot set a 0 line edit");
        return;
    }
 
    if (edit == d->lineEdit)
        return;
 
    edit->setText(currentText());
    delete d->lineEdit;
 
    d->lineEdit = edit;
#ifndef QT_NO_IM
    qt_widget_private(d->lineEdit)->inheritsInputMethodHints = 1;
#endif
    if (d->lineEdit->parent() != this)
        d->lineEdit->setParent(this);
    connect(d->lineEdit, SIGNAL(returnPressed()), this, SLOT(_q_returnPressed()));
    connect(d->lineEdit, SIGNAL(editingFinished()), this, SLOT(_q_editingFinished()));
    connect(d->lineEdit, SIGNAL(textChanged(QString)), this, SIGNAL(editTextChanged(QString)));
    connect(d->lineEdit, SIGNAL(textChanged(QString)), this, SIGNAL(currentTextChanged(QString)));
    connect(d->lineEdit, SIGNAL(cursorPositionChanged(int,int)), this, SLOT(updateMicroFocus()));
    connect(d->lineEdit, SIGNAL(selectionChanged()), this, SLOT(updateMicroFocus()));
    connect(d->lineEdit->d_func()->control, SIGNAL(updateMicroFocus()), this, SLOT(updateMicroFocus()));
    d->lineEdit->setFrame(false);
    d->lineEdit->setContextMenuPolicy(Qt::NoContextMenu);
    d->updateFocusPolicy();
    d->lineEdit->setFocusProxy(this);
    d->lineEdit->setAttribute(Qt::WA_MacShowFocusRect, false);
 
#if QT_CONFIG(completer)
    // create a default completer
    if (!d->lineEdit->completer()) {
        QCompleter *completer = new QCompleter(d->model, d->lineEdit);
        completer->setCaseSensitivity(Qt::CaseInsensitive);
        completer->setCompletionMode(QCompleter::InlineCompletion);
        completer->setCompletionColumn(d->modelColumn);
 
#ifdef QT_KEYPAD_NAVIGATION
        // Editable combo boxes will have a completer that is set to UnfilteredPopupCompletion.
        // This means that when the user enters edit mode they are immediately presented with a
        // list of possible completions.
        if (QApplicationPrivate::keypadNavigationEnabled())
            completer->setCompletionMode(QCompleter::UnfilteredPopupCompletion);
#endif
        // sets up connections
        setCompleter(completer);
    }
#endif
 
    setAttribute(Qt::WA_InputMethodEnabled);
    d->updateLayoutDirection();
    d->updateLineEditGeometry();
    if (isVisible())
        d->lineEdit->show();
 
    update();
}
 
QLineEdit *QComboBox::lineEdit() const
{
    Q_D(const QComboBox);
    return d->lineEdit;
}
 
#ifndef QT_NO_VALIDATOR
void QComboBox::setValidator(const QValidator *v)
{
    Q_D(QComboBox);
    if (d->lineEdit)
        d->lineEdit->setValidator(v);
}
 
const QValidator *QComboBox::validator() const
{
    Q_D(const QComboBox);
    return d->lineEdit ? d->lineEdit->validator() : nullptr;
}
#endif // QT_NO_VALIDATOR
 
#if QT_CONFIG(completer)
 
void QComboBox::setCompleter(QCompleter *c)
{
    Q_D(QComboBox);
    if (!d->lineEdit) {
        qWarning("Setting a QCompleter on non-editable QComboBox is not allowed.");
        return;
    }
    d->lineEdit->setCompleter(c);
    if (c) {
        connect(c, SIGNAL(activated(QModelIndex)), this, SLOT(_q_completerActivated(QModelIndex)));
        c->setWidget(this);
    }
}
 
QCompleter *QComboBox::completer() const
{
    Q_D(const QComboBox);
    return d->lineEdit ? d->lineEdit->completer() : nullptr;
}
 
#endif // QT_CONFIG(completer)
 
QAbstractItemDelegate *QComboBox::itemDelegate() const
{
    return view()->itemDelegate();
}
 
void QComboBox::setItemDelegate(QAbstractItemDelegate *delegate)
{
    if (Q_UNLIKELY(!delegate)) {
        qWarning("QComboBox::setItemDelegate: cannot set a 0 delegate");
        return;
    }
    view()->setItemDelegate(delegate);
}
 
QAbstractItemModel *QComboBox::model() const
{
    Q_D(const QComboBox);
    if (d->model == QAbstractItemModelPrivate::staticEmptyModel()) {
        QComboBox *that = const_cast<QComboBox*>(this);
        that->setModel(new QStandardItemModel(0, 1, that));
    }
    return d->model;
}
 
void QComboBox::setModel(QAbstractItemModel *model)
{
    Q_D(QComboBox);
 
    if (Q_UNLIKELY(!model)) {
        qWarning("QComboBox::setModel: cannot set a 0 model");
        return;
    }
 
    if (model == d->model)
        return;
 
#if QT_CONFIG(completer)
    if (d->lineEdit && d->lineEdit->completer())
        d->lineEdit->completer()->setModel(model);
#endif
    if (d->model) {
        disconnect(d->model, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
                   this, SLOT(_q_dataChanged(QModelIndex,QModelIndex)));
        disconnect(d->model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
                   this, SLOT(_q_updateIndexBeforeChange()));
        disconnect(d->model, SIGNAL(rowsInserted(QModelIndex,int,int)),
                   this, SLOT(_q_rowsInserted(QModelIndex,int,int)));
        disconnect(d->model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
                   this, SLOT(_q_updateIndexBeforeChange()));
        disconnect(d->model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
                   this, SLOT(_q_rowsRemoved(QModelIndex,int,int)));
        disconnect(d->model, SIGNAL(destroyed()),
                   this, SLOT(_q_modelDestroyed()));
        disconnect(d->model, SIGNAL(modelAboutToBeReset()),
                   this, SLOT(_q_updateIndexBeforeChange()));
        disconnect(d->model, SIGNAL(modelReset()),
                   this, SLOT(_q_modelReset()));
        if (d->model->QObject::parent() == this)
            delete d->model;
    }
 
    d->model = model;
 
    connect(model, SIGNAL(dataChanged(QModelIndex,QModelIndex)),
            this, SLOT(_q_dataChanged(QModelIndex,QModelIndex)));
    connect(model, SIGNAL(rowsAboutToBeInserted(QModelIndex,int,int)),
            this, SLOT(_q_updateIndexBeforeChange()));
    connect(model, SIGNAL(rowsInserted(QModelIndex,int,int)),
            this, SLOT(_q_rowsInserted(QModelIndex,int,int)));
    connect(model, SIGNAL(rowsAboutToBeRemoved(QModelIndex,int,int)),
            this, SLOT(_q_updateIndexBeforeChange()));
    connect(model, SIGNAL(rowsRemoved(QModelIndex,int,int)),
            this, SLOT(_q_rowsRemoved(QModelIndex,int,int)));
    connect(model, SIGNAL(destroyed()),
            this, SLOT(_q_modelDestroyed()));
    connect(model, SIGNAL(modelAboutToBeReset()),
            this, SLOT(_q_updateIndexBeforeChange()));
    connect(model, SIGNAL(modelReset()),
            this, SLOT(_q_modelReset()));
 
    if (d->container) {
        d->container->itemView()->setModel(model);
        connect(d->container->itemView()->selectionModel(),
                SIGNAL(currentChanged(QModelIndex,QModelIndex)),
                this, SLOT(_q_emitHighlighted(QModelIndex)), Qt::UniqueConnection);
    }
 
    setRootModelIndex(QModelIndex());
 
    d->trySetValidIndex();
    d->modelChanged();
}
 
QModelIndex QComboBox::rootModelIndex() const
{
    Q_D(const QComboBox);
    return QModelIndex(d->root);
}
 
void QComboBox::setRootModelIndex(const QModelIndex &index)
{
    Q_D(QComboBox);
    if (d->root == index)
        return;
    d->root = QPersistentModelIndex(index);
    view()->setRootIndex(index);
    update();
}
 
int QComboBox::currentIndex() const
{
    Q_D(const QComboBox);
    return d->currentIndex.row();
}
 
void QComboBox::setCurrentIndex(int index)
{
    Q_D(QComboBox);
    QModelIndex mi = index >= 0 ? d->model->index(index, d->modelColumn, d->root) : QModelIndex();
    d->setCurrentIndex(mi);
}
 
void QComboBox::setCurrentText(const QString &text)
{
    if (isEditable()) {
        setEditText(text);
    } else {
        const int i = findText(text);
        if (i > -1)
            setCurrentIndex(i);
    }
}
 
void QComboBoxPrivate::setCurrentIndex(const QModelIndex &mi)
{
    Q_Q(QComboBox);
 
    QModelIndex normalized = mi.sibling(mi.row(), modelColumn); // no-op if mi.column() == modelColumn
    if (!normalized.isValid())
        normalized = mi;    // Fallback to passed index.
 
    bool indexChanged = (normalized != currentIndex);
    if (indexChanged)
        currentIndex = QPersistentModelIndex(normalized);
    if (lineEdit) {
        const QString newText = itemText(normalized);
        if (lineEdit->text() != newText) {
            lineEdit->setText(newText); // may cause lineEdit -> nullptr (QTBUG-54191)
#if QT_CONFIG(completer)
            if (lineEdit && lineEdit->completer())
                lineEdit->completer()->setCompletionPrefix(newText);
#endif
        }
        updateLineEditGeometry();
    }
    // If the model was reset to an empty one, currentIndex will be invalidated
    // (because it's a QPersistentModelIndex), but the index change will never
    // be advertised. So an explicit check for this condition is needed.
    // The variable used for that check has to be reset when a previously valid
    // index becomes invalid.
    const bool modelResetToEmpty = !normalized.isValid() && indexBeforeChange != -1;
    if (modelResetToEmpty)
        indexBeforeChange = -1;
 
    if (indexChanged || modelResetToEmpty) {
        q->update();
        _q_emitCurrentIndexChanged(currentIndex);
    }
}
 
QString QComboBox::currentText() const
{
    Q_D(const QComboBox);
    if (d->lineEdit)
        return d->lineEdit->text();
    if (d->currentIndex.isValid())
        return d->itemText(d->currentIndex);
    return {};
}
 
QVariant QComboBox::currentData(int role) const
{
    Q_D(const QComboBox);
    return d->currentIndex.data(role);
}
 
QString QComboBox::itemText(int index) const
{
    Q_D(const QComboBox);
    QModelIndex mi = d->model->index(index, d->modelColumn, d->root);
    return d->itemText(mi);
}
 
QIcon QComboBox::itemIcon(int index) const
{
    Q_D(const QComboBox);
    QModelIndex mi = d->model->index(index, d->modelColumn, d->root);
    return d->itemIcon(mi);
}
 
QVariant QComboBox::itemData(int index, int role) const
{
    Q_D(const QComboBox);
    QModelIndex mi = d->model->index(index, d->modelColumn, d->root);
    return d->model->data(mi, role);
}
 
void QComboBox::insertItem(int index, const QIcon &icon, const QString &text, const QVariant &userData)
{
    Q_D(QComboBox);
    int itemCount = count();
    index = qBound(0, index, itemCount);
    if (index >= d->maxCount)
        return;
 
    // For the common case where we are using the built in QStandardItemModel
    // construct a QStandardItem, reducing the number of expensive signals from the model
    if (QStandardItemModel *m = qobject_cast<QStandardItemModel*>(d->model)) {
        QStandardItem *item = new QStandardItem(text);
        if (!icon.isNull()) item->setData(icon, Qt::DecorationRole);
        if (userData.isValid()) item->setData(userData, Qt::UserRole);
        m->insertRow(index, item);
        ++itemCount;
    } else {
        d->inserting = true;
        if (d->model->insertRows(index, 1, d->root)) {
            QModelIndex item = d->model->index(index, d->modelColumn, d->root);
            if (icon.isNull() && !userData.isValid()) {
                d->model->setData(item, text, Qt::EditRole);
            } else {
                QMap<int, QVariant> values;
                if (!text.isNull()) values.insert(Qt::EditRole, text);
                if (!icon.isNull()) values.insert(Qt::DecorationRole, icon);
                if (userData.isValid()) values.insert(Qt::UserRole, userData);
                if (!values.isEmpty()) d->model->setItemData(item, values);
            }
            d->inserting = false;
            d->_q_rowsInserted(d->root, index, index);
            ++itemCount;
        } else {
            d->inserting = false;
        }
    }
 
    if (itemCount > d->maxCount)
        d->model->removeRows(itemCount - 1, itemCount - d->maxCount, d->root);
}
 
void QComboBox::insertItems(int index, const QStringList &list)
{
    Q_D(QComboBox);
    if (list.isEmpty())
        return;
    index = qBound(0, index, count());
    int insertCount = qMin(d->maxCount - index, list.size());
    if (insertCount <= 0)
        return;
    // For the common case where we are using the built in QStandardItemModel
    // construct a QStandardItem, reducing the number of expensive signals from the model
    if (QStandardItemModel *m = qobject_cast<QStandardItemModel*>(d->model)) {
        QList<QStandardItem *> items;
        items.reserve(insertCount);
        QStandardItem *hiddenRoot = m->invisibleRootItem();
        for (int i = 0; i < insertCount; ++i)
            items.append(new QStandardItem(list.at(i)));
        hiddenRoot->insertRows(index, items);
    } else {
        d->inserting = true;
        if (d->model->insertRows(index, insertCount, d->root)) {
            QModelIndex item;
            for (int i = 0; i < insertCount; ++i) {
                item = d->model->index(i+index, d->modelColumn, d->root);
                d->model->setData(item, list.at(i), Qt::EditRole);
            }
            d->inserting = false;
            d->_q_rowsInserted(d->root, index, index + insertCount - 1);
        } else {
            d->inserting = false;
        }
    }
 
    int mc = count();
    if (mc > d->maxCount)
        d->model->removeRows(d->maxCount, mc - d->maxCount, d->root);
}
 
void QComboBox::insertSeparator(int index)
{
    Q_D(QComboBox);
    int itemCount = count();
    index = qBound(0, index, itemCount);
    if (index >= d->maxCount)
        return;
    insertItem(index, QIcon(), QString());
    QComboBoxDelegate::setSeparator(d->model, d->model->index(index, 0, d->root));
}
 
void QComboBox::removeItem(int index)
{
    Q_D(QComboBox);
    if (index < 0 || index >= count())
        return;
    d->model->removeRows(index, 1, d->root);
}
 
void QComboBox::setItemText(int index, const QString &text)
{
    Q_D(const QComboBox);
    QModelIndex item = d->model->index(index, d->modelColumn, d->root);
    if (item.isValid()) {
        d->model->setData(item, text, Qt::EditRole);
    }
}
 
void QComboBox::setItemIcon(int index, const QIcon &icon)
{
    Q_D(const QComboBox);
    QModelIndex item = d->model->index(index, d->modelColumn, d->root);
    if (item.isValid()) {
        d->model->setData(item, icon, Qt::DecorationRole);
    }
}
 
void QComboBox::setItemData(int index, const QVariant &value, int role)
{
    Q_D(const QComboBox);
    QModelIndex item = d->model->index(index, d->modelColumn, d->root);
    if (item.isValid()) {
        d->model->setData(item, value, role);
    }
}
 
QAbstractItemView *QComboBox::view() const
{
    Q_D(const QComboBox);
    return const_cast<QComboBoxPrivate*>(d)->viewContainer()->itemView();
}
 
void QComboBox::setView(QAbstractItemView *itemView)
{
    Q_D(QComboBox);
    if (Q_UNLIKELY(!itemView)) {
        qWarning("QComboBox::setView: cannot set a 0 view");
        return;
    }
 
    if (itemView->model() != d->model)
        itemView->setModel(d->model);
    d->viewContainer()->setItemView(itemView);
}
 
QSize QComboBox::minimumSizeHint() const
{
    Q_D(const QComboBox);
    return d->recomputeSizeHint(d->minimumSizeHint);
}
 
QSize QComboBox::sizeHint() const
{
    Q_D(const QComboBox);
    return d->recomputeSizeHint(d->sizeHint);
}
 
#ifdef Q_OS_MAC
void QComboBoxPrivate::cleanupNativePopup()
{
    if (!m_platformMenu)
        return;
 
    int count = int(m_platformMenu->tag());
    for (int i = 0; i < count; ++i)
        m_platformMenu->menuItemAt(i)->deleteLater();
 
    delete m_platformMenu;
    m_platformMenu = 0;
}
 
bool QComboBoxPrivate::showNativePopup()
{
    Q_Q(QComboBox);
 
    cleanupNativePopup();
 
    QPlatformTheme *theme = QGuiApplicationPrivate::instance()->platformTheme();
    m_platformMenu = theme->createPlatformMenu();
    if (!m_platformMenu)
        return false;
 
    int itemsCount = q->count();
    m_platformMenu->setTag(quintptr(itemsCount));
 
    QPlatformMenuItem *currentItem = nullptr;
    int currentIndex = q->currentIndex();
 
    for (int i = 0; i < itemsCount; ++i) {
        QPlatformMenuItem *item = theme->createPlatformMenuItem();
        QModelIndex rowIndex = model->index(i, modelColumn, root);
        QVariant textVariant = model->data(rowIndex, Qt::EditRole);
        item->setText(textVariant.toString());
        QVariant iconVariant = model->data(rowIndex, Qt::DecorationRole);
        const Qt::ItemFlags itemFlags = model->flags(rowIndex);
        if (iconVariant.canConvert<QIcon>())
            item->setIcon(iconVariant.value<QIcon>());
        item->setCheckable(true);
        item->setChecked(i == currentIndex);
        item->setEnabled(itemFlags & Qt::ItemIsEnabled);
        if (!currentItem || i == currentIndex)
            currentItem = item;
 
        IndexSetter setter = { i, q };
        QObject::connect(item, &QPlatformMenuItem::activated, q, setter);
 
        m_platformMenu->insertMenuItem(item, 0);
        m_platformMenu->syncMenuItem(item);
    }
 
    QWindow *tlw = q->window()->windowHandle();
    m_platformMenu->setFont(q->font());
    m_platformMenu->setMinimumWidth(q->rect().width());
    QPoint offset = QPoint(0, 7);
    if (q->testAttribute(Qt::WA_MacSmallSize))
        offset = QPoint(-1, 7);
    else if (q->testAttribute(Qt::WA_MacMiniSize))
        offset = QPoint(-2, 6);
 
    const QRect targetRect = QRect(tlw->mapFromGlobal(q->mapToGlobal(offset)), QSize());
    m_platformMenu->showPopup(tlw, QHighDpi::toNativePixels(targetRect, tlw), currentItem);
 
#ifdef Q_OS_MACOS
    // The Cocoa popup will swallow any mouse release event.
    // We need to fake one here to un-press the button.
    QMouseEvent mouseReleased(QEvent::MouseButtonRelease, q->pos(), q->mapToGlobal(QPoint(0, 0)),
                              Qt::LeftButton, Qt::MouseButtons(Qt::LeftButton), {});
    QCoreApplication::sendEvent(q, &mouseReleased);
#endif
 
    return true;
}
 
#endif // Q_OS_MAC
 
void QComboBox::showPopup()
{
    Q_D(QComboBox);
    if (count() <= 0)
        return;
 
    QStyle * const style = this->style();
    QStyleOptionComboBox opt;
    initStyleOption(&opt);
    const bool usePopup = style->styleHint(QStyle::SH_ComboBox_Popup, &opt, this);
 
#ifdef Q_OS_MAC
    if (usePopup
        && (!d->container
            || (view()->metaObject()->className() == QByteArray("QComboBoxListView")
                && view()->itemDelegate()->metaObject()->className() == QByteArray("QComboMenuDelegate")))
        && style->styleHint(QStyle::SH_ComboBox_UseNativePopup, &opt, this)
        && d->showNativePopup())
        return;
#endif // Q_OS_MAC
 
    // set current item and select it
    QItemSelectionModel::SelectionFlags selectionMode = QItemSelectionModel::ClearAndSelect;
    if (view()->selectionBehavior() == QAbstractItemView::SelectRows)
        selectionMode.setFlag(QItemSelectionModel::Rows);
    view()->selectionModel()->setCurrentIndex(d->currentIndex, selectionMode);
    QComboBoxPrivateContainer* container = d->viewContainer();
    QRect listRect(style->subControlRect(QStyle::CC_ComboBox, &opt,
                                         QStyle::SC_ComboBoxListBoxPopup, this));
    QRect screen = d->popupGeometry(mapToGlobal(listRect.topLeft()));
 
    QPoint below = mapToGlobal(listRect.bottomLeft());
    int belowHeight = screen.bottom() - below.y();
    QPoint above = mapToGlobal(listRect.topLeft());
    int aboveHeight = above.y() - screen.y();
    bool boundToScreen = !window()->testAttribute(Qt::WA_DontShowOnScreen);
 
    {
        int listHeight = 0;
        int count = 0;
        QStack<QModelIndex> toCheck;
        toCheck.push(view()->rootIndex());
#if QT_CONFIG(treeview)
        QTreeView *treeView = qobject_cast<QTreeView*>(view());
        if (treeView && treeView->header() && !treeView->header()->isHidden())
            listHeight += treeView->header()->height();
#endif
        while (!toCheck.isEmpty()) {
            QModelIndex parent = toCheck.pop();
            for (int i = 0, end = d->model->rowCount(parent); i < end; ++i) {
                QModelIndex idx = d->model->index(i, d->modelColumn, parent);
                if (!idx.isValid())
                    continue;
                listHeight += view()->visualRect(idx).height();
#if QT_CONFIG(treeview)
                if (d->model->hasChildren(idx) && treeView && treeView->isExpanded(idx))
                    toCheck.push(idx);
#endif
                ++count;
                if (!usePopup && count >= d->maxVisibleItems) {
                    toCheck.clear();
                    break;
                }
            }
        }
        if (count > 1)
            listHeight += (count - 1) * container->spacing();
        listRect.setHeight(listHeight);
    }
 
    {
        // add the spacing for the grid on the top and the bottom;
        int heightMargin = container->topMargin()  + container->bottomMargin();
 
        // add the frame of the container
        const QMargins cm = container->contentsMargins();
        heightMargin += cm.top() + cm.bottom();
 
        //add the frame of the view
        const QMargins vm = view()->contentsMargins();
        heightMargin += vm.top() + vm.bottom();
        heightMargin += static_cast<QAbstractScrollAreaPrivate *>(QObjectPrivate::get(view()))->top;
        heightMargin += static_cast<QAbstractScrollAreaPrivate *>(QObjectPrivate::get(view()))->bottom;
 
        listRect.setHeight(listRect.height() + heightMargin);
    }
 
    // Add space for margin at top and bottom if the style wants it.
    if (usePopup)
        listRect.setHeight(listRect.height() + style->pixelMetric(QStyle::PM_MenuVMargin, &opt, this) * 2);
 
    // Make sure the popup is wide enough to display its contents.
    if (usePopup) {
        const int diff = d->computeWidthHint() - width();
        if (diff > 0)
            listRect.setWidth(listRect.width() + diff);
    }
 
    //we need to activate the layout to make sure the min/maximum size are set when the widget was not yet show
    container->layout()->activate();
    //takes account of the minimum/maximum size of the container
    listRect.setSize( listRect.size().expandedTo(container->minimumSize())
                      .boundedTo(container->maximumSize()));
 
    // make sure the widget fits on screen
    if (boundToScreen) {
        if (listRect.width() > screen.width() )
            listRect.setWidth(screen.width());
        if (mapToGlobal(listRect.bottomRight()).x() > screen.right()) {
            below.setX(screen.x() + screen.width() - listRect.width());
            above.setX(screen.x() + screen.width() - listRect.width());
        }
        if (mapToGlobal(listRect.topLeft()).x() < screen.x() ) {
            below.setX(screen.x());
            above.setX(screen.x());
        }
    }
 
    if (usePopup) {
        // Position horizontally.
        listRect.moveLeft(above.x());
 
        // Position vertically so the currently selected item lines up
        // with the combo box. In order to do that, make sure that the item
        // view is scrolled to the top first, otherwise calls to view()->visualRect()
        // will return the geometry the selected item had the last time the popup
        // was visible (and perhaps scrolled). And this will not match the geometry
        // it will actually have when we resize the container to fit all the items
        // further down in this function.
        view()->scrollToTop();
        const QRect currentItemRect = view()->visualRect(view()->currentIndex());
        const int offset = listRect.top() - currentItemRect.top();
        listRect.moveTop(above.y() + offset - listRect.top());
 
        // Clamp the listRect height and vertical position so we don't expand outside the
        // available screen geometry.This may override the vertical position, but it is more
        // important to show as much as possible of the popup.
        const int height = !boundToScreen ? listRect.height() : qMin(listRect.height(), screen.height());
        listRect.setHeight(height);
 
        if (boundToScreen) {
            if (listRect.top() < screen.top())
                listRect.moveTop(screen.top());
            if (listRect.bottom() > screen.bottom())
                listRect.moveBottom(screen.bottom());
        }
    } else if (!boundToScreen || listRect.height() <= belowHeight) {
        listRect.moveTopLeft(below);
    } else if (listRect.height() <= aboveHeight) {
        listRect.moveBottomLeft(above);
    } else if (belowHeight >= aboveHeight) {
        listRect.setHeight(belowHeight);
        listRect.moveTopLeft(below);
    } else {
        listRect.setHeight(aboveHeight);
        listRect.moveBottomLeft(above);
    }
 
    if (qApp) {
        QGuiApplication::inputMethod()->reset();
    }
 
    const QScrollBar *sb = view()->horizontalScrollBar();
    const auto needHorizontalScrollBar = [this, sb]{
        const Qt::ScrollBarPolicy policy = view()->horizontalScrollBarPolicy();
        return (policy == Qt::ScrollBarAsNeeded || policy == Qt::ScrollBarAlwaysOn)
               && sb->minimum() < sb->maximum();
    };
    const bool neededHorizontalScrollBar = needHorizontalScrollBar();
    if (neededHorizontalScrollBar)
        listRect.adjust(0, 0, 0, sb->height());
 
    // Hide the scrollers here, so that the listrect gets the full height of the container
    // If the scrollers are truly needed, the later call to container->updateScrollers()
    // will make them visible again.
    container->hideScrollers();
    container->setGeometry(listRect);
 
#ifndef Q_OS_MAC
    const bool updatesEnabled = container->updatesEnabled();
#endif
 
#if QT_CONFIG(effects)
    bool scrollDown = (listRect.topLeft() == below);
    if (QApplication::isEffectEnabled(Qt::UI_AnimateCombo)
        && !style->styleHint(QStyle::SH_ComboBox_Popup, &opt, this) && !window()->testAttribute(Qt::WA_DontShowOnScreen))
        qScrollEffect(container, scrollDown ? QEffects::DownScroll : QEffects::UpScroll, 150);
#endif
 
// Don't disable updates on OS X. Windows are displayed immediately on this platform,
// which means that the window will be visible before the call to container->show() returns.
// If updates are disabled at this point we'll miss our chance at painting the popup
// menu before it's shown, causing flicker since the window then displays the standard gray
// background.
#ifndef Q_OS_MAC
    container->setUpdatesEnabled(false);
#endif
 
    bool startTimer = !container->isVisible();
    container->raise();
    container->create();
    if (QWindow *containerWindow = qt_widget_private(container)->windowHandle(QWidgetPrivate::WindowHandleMode::TopLevel)) {
        QScreen *currentScreen = d->associatedScreen();
        if (currentScreen && !currentScreen->virtualSiblings().contains(containerWindow->screen())) {
            containerWindow->setScreen(currentScreen);
 
            // This seems to workaround an issue in xcb+multi GPU+multiscreen
            // environment where the window might not always show up when screen
            // is changed.
            container->hide();
        }
    }
    container->show();
    if (!neededHorizontalScrollBar && needHorizontalScrollBar()) {
        listRect.adjust(0, 0, 0, sb->height());
        container->setGeometry(listRect);
    }
 
    container->updateScrollers();
    view()->setFocus();
 
    view()->scrollTo(view()->currentIndex(),
                     style->styleHint(QStyle::SH_ComboBox_Popup, &opt, this)
                             ? QAbstractItemView::PositionAtCenter
                             : QAbstractItemView::EnsureVisible);
 
#ifndef Q_OS_MAC
    container->setUpdatesEnabled(updatesEnabled);
#endif
 
    container->update();
    if (startTimer) {
        container->popupTimer.start();
        container->maybeIgnoreMouseButtonRelease = true;
    }
}
 
void QComboBox::hidePopup()
{
    Q_D(QComboBox);
    if (d->hidingPopup)
        return;
    d->hidingPopup = true;
    // can't use QBoolBlocker on a bitfield
    auto resetHidingPopup = qScopeGuard([d]{
        d->hidingPopup = false;
    });
 
    if (!d->container || !d->container->isVisible())
        return;
 
#if QT_CONFIG(effects)
    QItemSelectionModel *selectionModel = d->container->itemView()
                                        ? d->container->itemView()->selectionModel() : nullptr;
    // Flash selected/triggered item (if any) before hiding the popup.
    if (style()->styleHint(QStyle::SH_Menu_FlashTriggeredItem) &&
        selectionModel && selectionModel->hasSelection()) {
        const QItemSelection selection = selectionModel->selection();
 
        QTimer::singleShot(0, d->container, [d, selection, selectionModel]{
            QSignalBlocker modelBlocker(d->model);
            QSignalBlocker viewBlocker(d->container->itemView());
            QSignalBlocker containerBlocker(d->container);
 
            // Deselect item and wait 60 ms.
            selectionModel->select(selection, QItemSelectionModel::Toggle);
            QTimer::singleShot(60, d->container, [d, selection, selectionModel]{
                QSignalBlocker modelBlocker(d->model);
                QSignalBlocker viewBlocker(d->container->itemView());
                QSignalBlocker containerBlocker(d->container);
                selectionModel->select(selection, QItemSelectionModel::Toggle);
                QTimer::singleShot(20, d->container, [d] {
                    d->doHidePopup();
                });
            });
        });
    } else
#endif // QT_CONFIG(effects)
    {
        d->doHidePopup();
    }
}
 
void QComboBoxPrivate::doHidePopup()
{
    if (container && container->isVisible())
        container->hide();
 
    _q_resetButton();
}
 
void QComboBoxPrivate::updateCurrentText(const QString &text)
{
    if (text == currentText)
        return;
 
    currentText = text;
    emit q_func()->currentTextChanged(text);
}
 
void QComboBox::clear()
{
    Q_D(QComboBox);
    d->model->removeRows(0, d->model->rowCount(d->root), d->root);
#if QT_CONFIG(accessibility)
    QAccessibleValueChangeEvent event(this, QString());
    QAccessible::updateAccessibility(&event);
#endif
}
 
void QComboBox::clearEditText()
{
    Q_D(QComboBox);
    if (d->lineEdit)
        d->lineEdit->clear();
#if QT_CONFIG(accessibility)
    QAccessibleValueChangeEvent event(this, QString());
    QAccessible::updateAccessibility(&event);
#endif
}
 
void QComboBox::setEditText(const QString &text)
{
    Q_D(QComboBox);
    if (d->lineEdit)
        d->lineEdit->setText(text);
#if QT_CONFIG(accessibility)
    QAccessibleValueChangeEvent event(this, text);
    QAccessible::updateAccessibility(&event);
#endif
}
 
void QComboBox::focusInEvent(QFocusEvent *e)
{
    Q_D(QComboBox);
    update();
    if (d->lineEdit) {
        d->lineEdit->event(e);
#if QT_CONFIG(completer)
        if (d->lineEdit->completer())
            d->lineEdit->completer()->setWidget(this);
#endif
    }
}
 
void QComboBox::focusOutEvent(QFocusEvent *e)
{
    Q_D(QComboBox);
    update();
    if (d->lineEdit)
        d->lineEdit->event(e);
}
 
void QComboBox::changeEvent(QEvent *e)
{
    Q_D(QComboBox);
    switch (e->type()) {
    case QEvent::StyleChange:
        if (d->container)
            d->container->updateStyleSettings();
        d->updateDelegate();
#ifdef Q_OS_MAC
    case QEvent::MacSizeChange:
#endif
        d->sizeHint = QSize(); // invalidate size hint
        d->minimumSizeHint = QSize();
        d->updateLayoutDirection();
        if (d->lineEdit)
            d->updateLineEditGeometry();
        d->setLayoutItemMargins(QStyle::SE_ComboBoxLayoutItem);
 
        if (e->type() == QEvent::MacSizeChange) {
            QPlatformTheme::Font f = QPlatformTheme::SystemFont;
            if (testAttribute(Qt::WA_MacSmallSize))
                f = QPlatformTheme::SmallFont;
            else if (testAttribute(Qt::WA_MacMiniSize))
                f = QPlatformTheme::MiniFont;
            if (const QFont *platformFont = QApplicationPrivate::platformTheme()->font(f)) {
                QFont f = font();
                f.setPointSizeF(platformFont->pointSizeF());
                setFont(f);
            }
        }
        // ### need to update scrollers etc. as well here
        break;
    case QEvent::EnabledChange:
        if (!isEnabled())
            hidePopup();
        break;
    case QEvent::PaletteChange: {
        d->updateViewContainerPaletteAndOpacity();
        break;
    }
    case QEvent::FontChange: {
        d->sizeHint = QSize(); // invalidate size hint
        d->viewContainer()->setFont(font());
        d->viewContainer()->itemView()->doItemsLayout();
        if (d->lineEdit)
            d->updateLineEditGeometry();
        break;
    }
    default:
        break;
    }
    QWidget::changeEvent(e);
}
 
void QComboBox::resizeEvent(QResizeEvent *)
{
    Q_D(QComboBox);
    d->updateLineEditGeometry();
}
 
void QComboBox::paintEvent(QPaintEvent *)
{
    QStylePainter painter(this);
    painter.setPen(palette().color(QPalette::Text));
 
    // draw the combobox frame, focusrect and selected etc.
    QStyleOptionComboBox opt;
    initStyleOption(&opt);
    painter.drawComplexControl(QStyle::CC_ComboBox, opt);
 
    if (currentIndex() < 0 && !placeholderText().isEmpty()) {
        opt.palette.setBrush(QPalette::ButtonText, opt.palette.placeholderText());
        opt.currentText = placeholderText();
    }
 
    // draw the icon and text
    painter.drawControl(QStyle::CE_ComboBoxLabel, opt);
}
 
void QComboBox::showEvent(QShowEvent *e)
{
    Q_D(QComboBox);
    if (!d->shownOnce && d->sizeAdjustPolicy == QComboBox::AdjustToContentsOnFirstShow) {
        d->sizeHint = QSize();
        updateGeometry();
    }
    d->shownOnce = true;
    QWidget::showEvent(e);
}
 
void QComboBox::hideEvent(QHideEvent *)
{
    hidePopup();
}
 
bool QComboBox::event(QEvent *event)
{
    Q_D(QComboBox);
    switch(event->type()) {
    case QEvent::LayoutDirectionChange:
    case QEvent::ApplicationLayoutDirectionChange:
        d->updateLayoutDirection();
        d->updateLineEditGeometry();
        break;
    case QEvent::HoverEnter:
    case QEvent::HoverLeave:
    case QEvent::HoverMove:
        if (const QHoverEvent *he = static_cast<const QHoverEvent *>(event))
            d->updateHoverControl(he->position().toPoint());
        break;
    case QEvent::ShortcutOverride:
        if (d->lineEdit)
            return d->lineEdit->event(event);
        break;
#ifdef QT_KEYPAD_NAVIGATION
    case QEvent::EnterEditFocus:
        if (d->lineEdit)
            d->lineEdit->event(event);  //so cursor starts
        break;
    case QEvent::LeaveEditFocus:
        if (d->lineEdit)
            d->lineEdit->event(event);  //so cursor stops
        break;
#endif
    default:
        break;
    }
    return QWidget::event(event);
}
 
void QComboBox::mousePressEvent(QMouseEvent *e)
{
    Q_D(QComboBox);
    if (!QGuiApplication::styleHints()->setFocusOnTouchRelease())
        d->showPopupFromMouseEvent(e);
}
 
void QComboBoxPrivate::showPopupFromMouseEvent(QMouseEvent *e)
{
    Q_Q(QComboBox);
    QStyleOptionComboBox opt;
    q->initStyleOption(&opt);
    QStyle::SubControl sc = q->style()->hitTestComplexControl(QStyle::CC_ComboBox, &opt, e->position().toPoint(), q);
 
    if (e->button() == Qt::LeftButton
            && !(sc == QStyle::SC_None && e->type() == QEvent::MouseButtonRelease)
            && (sc == QStyle::SC_ComboBoxArrow || !q->isEditable())
            && !viewContainer()->isVisible()) {
        if (sc == QStyle::SC_ComboBoxArrow)
            updateArrow(QStyle::State_Sunken);
#ifdef QT_KEYPAD_NAVIGATION
        //if the container already exists, then d->viewContainer() is safe to call
        if (container) {
#else
        if (true) {
#endif
            // We've restricted the next couple of lines, because by not calling
            // viewContainer(), we avoid creating the QComboBoxPrivateContainer.
            viewContainer()->initialClickPosition = q->mapToGlobal(e->position().toPoint());
        }
        q->showPopup();
        // The code below ensures that regular mousepress and pick item still works
        // If it was not called the viewContainer would ignore event since it didn't have
        // a mousePressEvent first.
        if (viewContainer()) {
            viewContainer()->blockMouseReleaseTimer.start(QApplication::doubleClickInterval());
            viewContainer()->maybeIgnoreMouseButtonRelease = false;
        }
    } else {
#ifdef QT_KEYPAD_NAVIGATION
        if (QApplicationPrivate::keypadNavigationEnabled() && sc == QStyle::SC_ComboBoxEditField && lineEdit) {
            lineEdit->event(e);  //so lineedit can move cursor, etc
            return;
        }
#endif
        e->ignore();
    }
}
 
void QComboBox::mouseReleaseEvent(QMouseEvent *e)
{
    Q_D(QComboBox);
    d->updateArrow(QStyle::State_None);
    if (QGuiApplication::styleHints()->setFocusOnTouchRelease() && hasFocus())
        d->showPopupFromMouseEvent(e);
}
 
void QComboBox::keyPressEvent(QKeyEvent *e)
{
    Q_D(QComboBox);
 
#if QT_CONFIG(completer)
    if (const auto *cmpltr = completer()) {
        const auto *popup = QCompleterPrivate::get(cmpltr)->popup;
        if (popup && popup->isVisible()) {
            // provide same autocompletion support as line edit
            d->lineEdit->event(e);
            return;
        }
    }
#endif
 
    enum Move { NoMove=0 , MoveUp , MoveDown , MoveFirst , MoveLast};
 
    Move move = NoMove;
    int newIndex = currentIndex();
 
    bool pressLikeButton = !d->lineEdit;
#ifdef QT_KEYPAD_NAVIGATION
    pressLikeButton |= QApplicationPrivate::keypadNavigationEnabled() && !hasEditFocus();
#endif
    auto key = e->key();
    if (pressLikeButton) {
        const auto buttonPressKeys = QGuiApplicationPrivate::platformTheme()
                                             ->themeHint(QPlatformTheme::ButtonPressKeys)
                                             .value<QList<Qt::Key>>();
        if (buttonPressKeys.contains(key)) {
            showPopup();
            return;
        }
    }
 
    switch (key) {
    case Qt::Key_Up:
        if (e->modifiers() & Qt::ControlModifier)
            break; // pass to line edit for auto completion
        Q_FALLTHROUGH();
    case Qt::Key_PageUp:
#ifdef QT_KEYPAD_NAVIGATION
        if (QApplicationPrivate::keypadNavigationEnabled())
            e->ignore();
        else
#endif
        move = MoveUp;
        break;
    case Qt::Key_Down:
        if (e->modifiers() & Qt::AltModifier) {
            showPopup();
            return;
        } else if (e->modifiers() & Qt::ControlModifier)
            break; // pass to line edit for auto completion
        Q_FALLTHROUGH();
    case Qt::Key_PageDown:
#ifdef QT_KEYPAD_NAVIGATION
        if (QApplicationPrivate::keypadNavigationEnabled())
            e->ignore();
        else
#endif
        move = MoveDown;
        break;
    case Qt::Key_Home:
        if (!d->lineEdit)
            move = MoveFirst;
        break;
    case Qt::Key_End:
        if (!d->lineEdit)
            move = MoveLast;
        break;
    case Qt::Key_F4:
        if (!e->modifiers()) {
            showPopup();
            return;
        }
        break;
    case Qt::Key_Enter:
    case Qt::Key_Return:
    case Qt::Key_Escape:
        if (!d->lineEdit)
            e->ignore();
        break;
#ifdef QT_KEYPAD_NAVIGATION
    case Qt::Key_Left:
    case Qt::Key_Right:
        if (QApplicationPrivate::keypadNavigationEnabled() && !hasEditFocus())
            e->ignore();
        break;
    case Qt::Key_Back:
        if (QApplicationPrivate::keypadNavigationEnabled()) {
            if (!hasEditFocus() || !d->lineEdit)
                e->ignore();
        } else {
            e->ignore(); // let the surrounding dialog have it
        }
        break;
#endif
    default:
#if QT_CONFIG(shortcut)
        if (d->container && d->container->isVisible() && e->matches(QKeySequence::Cancel)) {
            hidePopup();
            e->accept();
        }
#endif
 
        if (!d->lineEdit) {
            if (!e->text().isEmpty())
                d->keyboardSearchString(e->text());
            else
                e->ignore();
        }
    }
 
    const int rowCount = count();
 
    if (move != NoMove) {
        e->accept();
        switch (move) {
        case MoveFirst:
            newIndex = -1;
            Q_FALLTHROUGH();
        case MoveDown:
            newIndex++;
            while (newIndex < rowCount && !(d->model->index(newIndex, d->modelColumn, d->root).flags() & Qt::ItemIsEnabled))
                newIndex++;
            break;
        case MoveLast:
            newIndex = rowCount;
            Q_FALLTHROUGH();
        case MoveUp:
            newIndex--;
            while ((newIndex >= 0) && !(d->model->flags(d->model->index(newIndex,d->modelColumn,d->root)) & Qt::ItemIsEnabled))
                newIndex--;
            break;
        default:
            e->ignore();
            break;
        }
 
        if (newIndex >= 0 && newIndex < rowCount && newIndex != currentIndex()) {
            setCurrentIndex(newIndex);
            d->emitActivated(d->currentIndex);
        }
    } else if (d->lineEdit) {
        d->lineEdit->event(e);
    }
}
 
 
void QComboBox::keyReleaseEvent(QKeyEvent *e)
{
    Q_D(QComboBox);
    if (d->lineEdit)
        d->lineEdit->event(e);
    else
        QWidget::keyReleaseEvent(e);
}
 
#if QT_CONFIG(wheelevent)
void QComboBox::wheelEvent(QWheelEvent *e)
{
    Q_D(QComboBox);
    QStyleOptionComboBox opt;
    initStyleOption(&opt);
    if (style()->styleHint(QStyle::SH_ComboBox_AllowWheelScrolling, &opt, this) &&
        !d->viewContainer()->isVisible()) {
        const int rowCount = count();
        int newIndex = currentIndex();
        int delta = e->angleDelta().y();
 
        if (delta > 0) {
            newIndex--;
            while ((newIndex >= 0) && !(d->model->flags(d->model->index(newIndex,d->modelColumn,d->root)) & Qt::ItemIsEnabled))
                newIndex--;
        } else if (delta < 0) {
            newIndex++;
            while (newIndex < rowCount && !(d->model->index(newIndex, d->modelColumn, d->root).flags() & Qt::ItemIsEnabled))
                newIndex++;
        }
 
        if (newIndex >= 0 && newIndex < rowCount && newIndex != currentIndex()) {
            setCurrentIndex(newIndex);
            d->emitActivated(d->currentIndex);
        }
        e->accept();
    }
}
#endif
 
#ifndef QT_NO_CONTEXTMENU
void QComboBox::contextMenuEvent(QContextMenuEvent *e)
{
    Q_D(QComboBox);
    if (d->lineEdit) {
        Qt::ContextMenuPolicy p = d->lineEdit->contextMenuPolicy();
        d->lineEdit->setContextMenuPolicy(Qt::DefaultContextMenu);
        d->lineEdit->event(e);
        d->lineEdit->setContextMenuPolicy(p);
    }
}
#endif // QT_NO_CONTEXTMENU
 
void QComboBoxPrivate::keyboardSearchString(const QString &text)
{
    // use keyboardSearch from the listView so we do not duplicate code
    QAbstractItemView *view = viewContainer()->itemView();
    view->setCurrentIndex(currentIndex);
    int currentRow = view->currentIndex().row();
    view->keyboardSearch(text);
    if (currentRow != view->currentIndex().row()) {
        setCurrentIndex(view->currentIndex());
        emitActivated(currentIndex);
    }
}
 
void QComboBoxPrivate::modelChanged()
{
    Q_Q(QComboBox);
 
    if (sizeAdjustPolicy == QComboBox::AdjustToContents) {
        sizeHint = QSize();
        adjustComboBoxSize();
        q->updateGeometry();
    }
}
 
void QComboBox::inputMethodEvent(QInputMethodEvent *e)
{
    Q_D(QComboBox);
    if (d->lineEdit) {
        d->lineEdit->event(e);
    } else {
        if (!e->commitString().isEmpty())
            d->keyboardSearchString(e->commitString());
        else
            e->ignore();
    }
}
 
QVariant QComboBox::inputMethodQuery(Qt::InputMethodQuery query) const
{
    Q_D(const QComboBox);
    if (d->lineEdit)
        return d->lineEdit->inputMethodQuery(query);
    return QWidget::inputMethodQuery(query);
}
 
QVariant QComboBox::inputMethodQuery(Qt::InputMethodQuery query, const QVariant &argument) const
{
    Q_D(const QComboBox);
    if (d->lineEdit)
        return d->lineEdit->inputMethodQuery(query, argument);
    return QWidget::inputMethodQuery(query);
}
 
bool QComboBox::hasFrame() const
{
    Q_D(const QComboBox);
    return d->frame;
}
 
 
void QComboBox::setFrame(bool enable)
{
    Q_D(QComboBox);
    d->frame = enable;
    update();
    updateGeometry();
}
 
int QComboBox::modelColumn() const
{
    Q_D(const QComboBox);
    return d->modelColumn;
}
 
void QComboBox::setModelColumn(int visibleColumn)
{
    Q_D(QComboBox);
    d->modelColumn = visibleColumn;
    QListView *lv = qobject_cast<QListView *>(d->viewContainer()->itemView());
    if (lv)
        lv->setModelColumn(visibleColumn);
#if QT_CONFIG(completer)
    if (d->lineEdit && d->lineEdit->completer())
        d->lineEdit->completer()->setCompletionColumn(visibleColumn);
#endif
    setCurrentIndex(currentIndex()); //update the text to the text of the new column;
}
 
QT_END_NAMESPACE
 
#include "moc_qcombobox.cpp"
#include "moc_qcombobox_p.cpp"