qtoolbar.cpp

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// Copyright (C) 2016 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 "qtoolbar.h"
 
#include <qapplication.h>
#if QT_CONFIG(combobox)
#include <qcombobox.h>
#endif
#if QT_CONFIG(draganddrop)
#include <qdrag.h>
#endif
#include <qevent.h>
#include <qlayout.h>
#include <qmainwindow.h>
#include <qmenu.h>
#if QT_CONFIG(menubar)
#include <qmenubar.h>
#endif
#include <qmimedata.h>
#if QT_CONFIG(rubberband)
#include <qrubberband.h>
#endif
#include <qstylepainter.h>
#include <qstyleoption.h>
#include <qtoolbutton.h>
#include <qwidgetaction.h>
#include <qtimer.h>
#include <private/qwidgetaction_p.h>
#include <private/qmainwindowlayout_p.h>
#include <private/qhighdpiscaling_p.h>
 
#ifdef Q_OS_MACOS
#include <qpa/qplatformnativeinterface.h>
#endif
 
#include "qtoolbar_p.h"
#include "qtoolbarseparator_p.h"
#include "qtoolbarlayout_p.h"
 
#include  "qdebug.h"
 
#define POPUP_TIMER_INTERVAL 500
 
QT_BEGIN_NAMESPACE
 
using namespace Qt::StringLiterals;
 
// qmainwindow.cpp
extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
 
/******************************************************************************
** QToolBarPrivate
*/
 
void QToolBarPrivate::init()
{
    Q_Q(QToolBar);
    q->setSizePolicy(QSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed));
    q->setBackgroundRole(QPalette::Button);
    q->setAttribute(Qt::WA_Hover);
    q->setAttribute(Qt::WA_X11NetWmWindowTypeToolBar);
 
    QStyle *style = q->style();
    int e = style->pixelMetric(QStyle::PM_ToolBarIconSize, nullptr, q);
    iconSize = QSize(e, e);
 
    layout = new QToolBarLayout(q);
    layout->updateMarginAndSpacing();
 
    toggleViewAction = new QAction(q);
    toggleViewAction->setCheckable(true);
    q->setMovable(q->style()->styleHint(QStyle::SH_ToolBar_Movable, nullptr, q ));
    QObject::connect(toggleViewAction, SIGNAL(triggered(bool)), q, SLOT(_q_toggleView(bool)));
}
 
void QToolBarPrivate::_q_toggleView(bool b)
{
    Q_Q(QToolBar);
    if (b == q->isHidden()) {
        if (b)
            q->show();
        else
            q->close();
    }
}
 
void QToolBarPrivate::_q_updateIconSize(const QSize &sz)
{
    Q_Q(QToolBar);
    if (!explicitIconSize) {
        // iconSize not explicitly set
        q->setIconSize(sz);
        explicitIconSize = false;
    }
}
 
void QToolBarPrivate::_q_updateToolButtonStyle(Qt::ToolButtonStyle style)
{
    Q_Q(QToolBar);
    if (!explicitToolButtonStyle) {
        q->setToolButtonStyle(style);
        explicitToolButtonStyle = false;
    }
}
 
void QToolBarPrivate::updateWindowFlags(bool floating, bool unplug)
{
    Q_Q(QToolBar);
    Qt::WindowFlags flags = floating ? Qt::Tool : Qt::Widget;
 
    flags |= Qt::FramelessWindowHint;
 
    // If we are performing a platform drag the flag is not needed and we want to avoid recreating
    // the platform window when it would be removed later
    if (unplug && !QMainWindowLayout::needsPlatformDrag())
        flags |= Qt::X11BypassWindowManagerHint;
 
    q->setWindowFlags(flags);
}
 
void QToolBarPrivate::setWindowState(bool floating, bool unplug, const QRect &rect)
{
    Q_Q(QToolBar);
    bool visible = !q->isHidden();
    bool wasFloating = q->isFloating(); // ...is also currently using popup menus
 
    updateWindowFlags(floating, unplug);
 
    if (floating != wasFloating)
        layout->checkUsePopupMenu();
 
    if (!rect.isNull())
        q->setGeometry(rect);
 
    if (visible)
        q->show();
 
    if (floating != wasFloating)
        emit q->topLevelChanged(floating);
}
 
void QToolBarPrivate::initDrag(const QPoint &pos)
{
    Q_Q(QToolBar);
 
    if (state != nullptr)
        return;
 
    QMainWindow *win = qobject_cast<QMainWindow*>(parent);
    Q_ASSERT(win != nullptr);
    QMainWindowLayout *layout = qt_mainwindow_layout(win);
    Q_ASSERT(layout != nullptr);
    if (layout->pluggingWidget != nullptr) // the main window is animating a docking operation
        return;
 
    state = new DragState;
    state->pressPos = pos;
    state->dragging = false;
    state->moving = false;
    state->widgetItem = nullptr;
 
    if (q->isRightToLeft())
        state->pressPos = QPoint(q->width() - state->pressPos.x(), state->pressPos.y());
}
 
void QToolBarPrivate::startDrag(bool moving)
{
    Q_Q(QToolBar);
 
    Q_ASSERT(state != nullptr);
 
    if ((moving && state->moving) || state->dragging)
        return;
 
    QMainWindow *win = qobject_cast<QMainWindow*>(parent);
    Q_ASSERT(win != nullptr);
    QMainWindowLayout *layout = qt_mainwindow_layout(win);
    Q_ASSERT(layout != nullptr);
 
    const bool wasFloating = q->isFloating();
 
    if (!moving) {
        state->widgetItem = layout->unplug(q);
        Q_ASSERT(state->widgetItem != nullptr);
    }
    state->dragging = !moving;
    state->moving = moving;
 
#if QT_CONFIG(draganddrop)
    if (QMainWindowLayout::needsPlatformDrag() && state->dragging) {
        auto result = layout->performPlatformWidgetDrag(state->widgetItem, state->pressPos);
        if (result == Qt::IgnoreAction && !wasFloating) {
            layout->revert(state->widgetItem);
            delete state;
            state = nullptr;
        } else {
            endDrag();
        }
    }
#endif
}
 
void QToolBarPrivate::endDrag()
{
    Q_Q(QToolBar);
    Q_ASSERT(state != nullptr);
 
    q->releaseMouse();
 
    if (state->dragging) {
        QMainWindowLayout *layout = qt_mainwindow_layout(qobject_cast<QMainWindow *>(q->parentWidget()));
        Q_ASSERT(layout != nullptr);
 
        if (!layout->plug(state->widgetItem)) {
            if (q->isFloatable()) {
                layout->restore();
                setWindowState(true); // gets rid of the X11BypassWindowManager window flag
                                      // and activates the resizer
                q->activateWindow();
            } else {
                layout->revert(state->widgetItem);
            }
        }
    }
 
    delete state;
    state = nullptr;
}
 
bool QToolBarPrivate::mousePressEvent(QMouseEvent *event)
{
    Q_Q(QToolBar);
    QStyleOptionToolBar opt;
    q->initStyleOption(&opt);
    if (q->style()->subElementRect(QStyle::SE_ToolBarHandle, &opt, q).contains(event->position().toPoint()) == false) {
#ifdef Q_OS_MACOS
        // When using the unified toolbar on OS X, the user can click and
        // drag between toolbar contents to move the window. Make this work by
        // implementing the standard mouse-dragging code and then call
        // window->move() in mouseMoveEvent below.
        if (QMainWindow *mainWindow = qobject_cast<QMainWindow *>(parent)) {
            if (mainWindow->toolBarArea(q) == Qt::TopToolBarArea
                    && mainWindow->unifiedTitleAndToolBarOnMac()
                    && q->childAt(event->pos()) == 0) {
                macWindowDragging = true;
                macWindowDragPressPosition = event->pos();
                return true;
            }
        }
#endif
        return false;
    }
 
    if (event->button() != Qt::LeftButton)
        return true;
 
    if (!layout->movable())
        return true;
 
    initDrag(event->position().toPoint());
    return true;
}
 
bool QToolBarPrivate::mouseReleaseEvent(QMouseEvent*)
{
    // if we are peforming a platform drag ignore the release here and  end the drag when the actual
    // drag ends.
    if (QMainWindowLayout::needsPlatformDrag())
        return false;
 
    if (state != nullptr) {
        endDrag();
        return true;
    } else {
#ifdef Q_OS_MACOS
        if (!macWindowDragging)
            return false;
        macWindowDragging = false;
        macWindowDragPressPosition = QPoint();
        return true;
#endif
        return false;
    }
}
 
bool QToolBarPrivate::mouseMoveEvent(QMouseEvent *event)
{
    Q_Q(QToolBar);
 
    if (!state) {
#ifdef Q_OS_MACOS
        if (!macWindowDragging)
            return false;
        QWidget *w = q->window();
        const QPoint delta = event->pos() - macWindowDragPressPosition;
        w->move(w->pos() + delta);
        return true;
#endif
        return false;
    }
 
    QMainWindow *win = qobject_cast<QMainWindow*>(parent);
    if (win == nullptr)
        return true;
 
    QMainWindowLayout *layout = qt_mainwindow_layout(win);
    Q_ASSERT(layout != nullptr);
 
    if (layout->pluggingWidget == nullptr
        && (event->position().toPoint() - state->pressPos).manhattanLength() > QApplication::startDragDistance()) {
            const bool wasDragging = state->dragging;
            const bool moving = !q->isWindow() && (orientation == Qt::Vertical ?
                event->position().toPoint().x() >= 0 && event->position().toPoint().x() < q->width() :
                event->position().toPoint().y() >= 0 && event->position().toPoint().y() < q->height());
 
            startDrag(moving);
            if (!moving && !wasDragging)
                q->grabMouse();
    }
 
    if (!state) {
        q->releaseMouse();
        return true;
    }
 
    if (state->dragging) {
        QPoint pos = event->globalPosition().toPoint();
        // if we are right-to-left, we move so as to keep the right edge the same distance
        // from the mouse
        if (q->isLeftToRight())
            pos -= state->pressPos;
        else
            pos += QPoint(state->pressPos.x() - q->width(), -state->pressPos.y());
 
        q->move(pos);
        layout->hover(state->widgetItem, event->globalPosition().toPoint());
    } else if (state->moving) {
 
        const QPoint rtl(q->width() - state->pressPos.x(), state->pressPos.y()); //for RTL
        const QPoint globalPressPos = q->mapToGlobal(q->isRightToLeft() ? rtl : state->pressPos);
        int pos = 0;
 
        const QWindow *handle = q->window() ? q->window()->windowHandle() : nullptr;
        const QPoint delta = handle
                ? QHighDpi::fromNativePixels(event->globalPosition(), handle).toPoint()
                  - QHighDpi::fromNativePixels(globalPressPos, handle)
                : event->globalPosition().toPoint() - globalPressPos;
 
        if (orientation == Qt::Vertical) {
            pos = q->y() + delta.y();
        } else {
            if (q->isRightToLeft()) {
                pos = win->width() - q->width() - q->x()  - delta.x();
            } else {
                pos = q->x() + delta.x();
            }
        }
 
        layout->moveToolBar(q, pos);
    }
    return true;
}
 
void QToolBarPrivate::unplug(const QRect &_r)
{
    Q_Q(QToolBar);
    QRect r = _r;
    r.moveTopLeft(q->mapToGlobal(QPoint(0, 0)));
    setWindowState(true, true, r);
    layout->setExpanded(false);
}
 
void QToolBarPrivate::plug(const QRect &r)
{
    setWindowState(false, false, r);
}
 
/******************************************************************************
** QToolBar
*/
 
QToolBar::QToolBar(QWidget *parent)
    : QWidget(*new QToolBarPrivate, parent, { })
{
    Q_D(QToolBar);
    d->init();
}
 
QToolBar::QToolBar(const QString &title, QWidget *parent)
    : QToolBar(parent)
{
    setWindowTitle(title);
}
 
 
QToolBar::~QToolBar()
{
}
 
void QToolBar::setMovable(bool movable)
{
    Q_D(QToolBar);
    if (!movable == !d->movable)
        return;
    d->movable = movable;
    d->layout->invalidate();
    emit movableChanged(d->movable);
}
 
bool QToolBar::isMovable() const
{
    Q_D(const QToolBar);
    return d->movable;
}
 
bool QToolBar::isFloatable() const
{
    Q_D(const QToolBar);
    return d->floatable;
}
 
void QToolBar::setFloatable(bool floatable)
{
    Q_D(QToolBar);
    d->floatable = floatable;
}
 
bool QToolBar::isFloating() const
{
    return isWindow();
}
 
void QToolBar::setAllowedAreas(Qt::ToolBarAreas areas)
{
    Q_D(QToolBar);
    areas &= Qt::ToolBarArea_Mask;
    if (areas == d->allowedAreas)
        return;
    d->allowedAreas = areas;
    emit allowedAreasChanged(d->allowedAreas);
}
 
Qt::ToolBarAreas QToolBar::allowedAreas() const
{
    Q_D(const QToolBar);
    return d->allowedAreas;
}
 
void QToolBar::setOrientation(Qt::Orientation orientation)
{
    Q_D(QToolBar);
    if (orientation == d->orientation)
        return;
 
    d->orientation = orientation;
 
    if (orientation == Qt::Vertical)
        setSizePolicy(QSizePolicy(QSizePolicy::Fixed, QSizePolicy::Preferred));
    else
        setSizePolicy(QSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed));
 
    d->layout->invalidate();
    d->layout->activate();
 
    emit orientationChanged(d->orientation);
}
 
Qt::Orientation QToolBar::orientation() const
{ Q_D(const QToolBar); return d->orientation; }
 
QSize QToolBar::iconSize() const
{ Q_D(const QToolBar); return d->iconSize; }
 
void QToolBar::setIconSize(const QSize &iconSize)
{
    Q_D(QToolBar);
    QSize sz = iconSize;
    if (!sz.isValid()) {
        QMainWindow *mw = qobject_cast<QMainWindow *>(parentWidget());
        if (mw && mw->layout()) {
            QLayout *layout = mw->layout();
            int i = 0;
            QLayoutItem *item = nullptr;
            do {
                item = layout->itemAt(i++);
                if (item && (item->widget() == this))
                    sz = mw->iconSize();
            } while (!sz.isValid() && item != nullptr);
        }
    }
    if (!sz.isValid()) {
        const int metric = style()->pixelMetric(QStyle::PM_ToolBarIconSize, nullptr, this);
        sz = QSize(metric, metric);
    }
    if (d->iconSize != sz) {
        d->iconSize = sz;
        setMinimumSize(0, 0);
        emit iconSizeChanged(d->iconSize);
    }
    d->explicitIconSize = iconSize.isValid();
 
    d->layout->invalidate();
}
 
Qt::ToolButtonStyle QToolBar::toolButtonStyle() const
{ Q_D(const QToolBar); return d->toolButtonStyle; }
 
void QToolBar::setToolButtonStyle(Qt::ToolButtonStyle toolButtonStyle)
{
    Q_D(QToolBar);
    d->explicitToolButtonStyle = true;
    if (d->toolButtonStyle == toolButtonStyle)
        return;
    d->toolButtonStyle = toolButtonStyle;
    setMinimumSize(0, 0);
    emit toolButtonStyleChanged(d->toolButtonStyle);
}
 
void QToolBar::clear()
{
    QList<QAction *> actions = this->actions();
    for(int i = 0; i < actions.size(); i++)
        removeAction(actions.at(i));
}
 
QAction *QToolBar::addSeparator()
{
    QAction *action = new QAction(this);
    action->setSeparator(true);
    addAction(action);
    return action;
}
 
QAction *QToolBar::insertSeparator(QAction *before)
{
    QAction *action = new QAction(this);
    action->setSeparator(true);
    insertAction(before, action);
    return action;
}
 
QAction *QToolBar::addWidget(QWidget *widget)
{
    QWidgetAction *action = new QWidgetAction(this);
    action->setDefaultWidget(widget);
    action->d_func()->autoCreated = true;
    addAction(action);
    return action;
}
 
QAction *QToolBar::insertWidget(QAction *before, QWidget *widget)
{
    QWidgetAction *action = new QWidgetAction(this);
    action->setDefaultWidget(widget);
    action->d_func()->autoCreated = true;
    insertAction(before, action);
    return action;
}
 
QRect QToolBar::actionGeometry(QAction *action) const
{
    Q_D(const QToolBar);
 
    int index = d->layout->indexOf(action);
    if (index == -1)
        return QRect();
    return d->layout->itemAt(index)->widget()->geometry();
}
 
QAction *QToolBar::actionAt(const QPoint &p) const
{
    Q_D(const QToolBar);
    QWidget *widget = childAt(p);
    int index = d->layout->indexOf(widget);
    if (index == -1)
        return nullptr;
    QLayoutItem *item = d->layout->itemAt(index);
    return static_cast<QToolBarItem*>(item)->action;
}
 
void QToolBar::actionEvent(QActionEvent *event)
{
    Q_D(QToolBar);
    auto action = static_cast<QAction *>(event->action());
    QWidgetAction *widgetAction = qobject_cast<QWidgetAction *>(action);
 
    switch (event->type()) {
        case QEvent::ActionAdded: {
            Q_ASSERT_X(widgetAction == nullptr || d->layout->indexOf(widgetAction) == -1,
                        "QToolBar", "widgets cannot be inserted multiple times");
 
            // reparent the action to this toolbar if it has been created
            // using the addAction(text) etc. convenience functions, to
            // preserve Qt 4.1.x behavior. The widget is already
            // reparented to us due to the createWidget call inside
            // createItem()
            if (widgetAction != nullptr && widgetAction->d_func()->autoCreated)
                widgetAction->setParent(this);
 
            int index = d->layout->count();
            if (event->before()) {
                index = d->layout->indexOf(event->before());
                Q_ASSERT_X(index != -1, "QToolBar::insertAction", "internal error");
            }
            d->layout->insertAction(index, action);
            break;
        }
 
        case QEvent::ActionChanged:
            d->layout->invalidate();
            break;
 
        case QEvent::ActionRemoved: {
            int index = d->layout->indexOf(action);
            if (index != -1) {
                delete d->layout->takeAt(index);
            }
            break;
        }
 
        default:
            Q_ASSERT_X(false, "QToolBar::actionEvent", "internal error");
    }
}
 
void QToolBar::changeEvent(QEvent *event)
{
    Q_D(QToolBar);
    switch (event->type()) {
    case QEvent::WindowTitleChange:
        d->toggleViewAction->setText(windowTitle());
        break;
    case QEvent::StyleChange:
        d->layout->invalidate();
        if (!d->explicitIconSize)
            setIconSize(QSize());
        d->layout->updateMarginAndSpacing();
        break;
    case QEvent::LayoutDirectionChange:
        d->layout->invalidate();
        break;
    default:
        break;
    }
    QWidget::changeEvent(event);
}
 
void QToolBar::paintEvent(QPaintEvent *)
{
    Q_D(QToolBar);
 
    QPainter p(this);
    QStyle *style = this->style();
    QStyleOptionToolBar opt;
    initStyleOption(&opt);
 
    if (d->layout->expanded || d->layout->animating || isWindow()) {
        //if the toolbar is expended, we need to fill the background with the window color
        //because some styles may expects that.
        p.fillRect(opt.rect, palette().window());
        style->drawControl(QStyle::CE_ToolBar, &opt, &p, this);
        style->drawPrimitive(QStyle::PE_FrameMenu, &opt, &p, this);
    } else {
        style->drawControl(QStyle::CE_ToolBar, &opt, &p, this);
    }
 
    opt.rect = style->subElementRect(QStyle::SE_ToolBarHandle, &opt, this);
    if (opt.rect.isValid())
        style->drawPrimitive(QStyle::PE_IndicatorToolBarHandle, &opt, &p, this);
}
 
/*
    Checks if an expanded toolbar has to wait for this popup to close before
    the toolbar collapses. This is true if
    1) the popup has the toolbar in its parent chain,
    2) the popup is a menu whose menuAction is somewhere in the toolbar.
*/
static bool waitForPopup(QToolBar *tb, QWidget *popup)
{
    if (popup == nullptr || popup->isHidden())
        return false;
 
    QWidget *w = popup;
    while (w != nullptr) {
        if (w == tb)
            return true;
        w = w->parentWidget();
    }
 
    QMenu *menu = qobject_cast<QMenu*>(popup);
    if (menu == nullptr)
        return false;
 
    const QAction *action = menu->menuAction();
    for (auto object : action->associatedObjects()) {
        if (QWidget *widget = qobject_cast<QWidget*>(object)) {
            if (waitForPopup(tb, widget))
                return true;
        }
    }
 
    return false;
}
 
#ifdef Q_OS_MACOS
static void enableMacToolBar(QToolBar *toolbar, bool enable)
{
    QPlatformNativeInterface *nativeInterface = QApplication::platformNativeInterface();
    if (!nativeInterface)
        return;
    QPlatformNativeInterface::NativeResourceForIntegrationFunction function =
        nativeInterface->nativeResourceFunctionForIntegration("setContentBorderAreaEnabled");
    if (!function)
        return; // Not Cocoa platform plugin.
 
    typedef void (*SetContentBorderAreaEnabledFunction)(QWindow *window, void *identifier, bool enabled);
    (reinterpret_cast<SetContentBorderAreaEnabledFunction>(function))(toolbar->window()->windowHandle(), toolbar, enable);
}
#endif
 
 
bool QToolBar::event(QEvent *event)
{
    Q_D(QToolBar);
 
    switch (event->type()) {
    case QEvent::Timer:
        if (d->waitForPopupTimer.timerId() == static_cast<QTimerEvent*>(event)->timerId()) {
            QWidget *w = QApplication::activePopupWidget();
            if (!waitForPopup(this, w)) {
                d->waitForPopupTimer.stop();
                if (!this->underMouse())
                    d->layout->setExpanded(false);
            }
        }
        break;
    case QEvent::Hide:
        if (!isHidden())
            break;
        Q_FALLTHROUGH();
    case QEvent::Show:
        d->toggleViewAction->setChecked(event->type() == QEvent::Show);
#ifdef Q_OS_MACOS
        enableMacToolBar(this, event->type() == QEvent::Show);
#endif
        emit visibilityChanged(event->type() == QEvent::Show);
        break;
    case QEvent::ParentChange:
        d->layout->checkUsePopupMenu();
        break;
 
    case QEvent::MouseButtonPress: {
        if (d->mousePressEvent(static_cast<QMouseEvent*>(event)))
            return true;
        break;
    }
    case QEvent::MouseButtonRelease:
        if (d->mouseReleaseEvent(static_cast<QMouseEvent*>(event)))
            return true;
        break;
    case QEvent::HoverEnter:
    case QEvent::HoverLeave:
        // there's nothing special to do here and we don't want to update the whole widget
        return true;
    case QEvent::HoverMove: {
#ifndef QT_NO_CURSOR
        QHoverEvent *e = static_cast<QHoverEvent*>(event);
        QStyleOptionToolBar opt;
        initStyleOption(&opt);
        if (style()->subElementRect(QStyle::SE_ToolBarHandle, &opt, this).contains(e->position().toPoint()))
            setCursor(Qt::SizeAllCursor);
        else
            unsetCursor();
#endif
        break;
    }
    case QEvent::MouseMove:
        if (d->mouseMoveEvent(static_cast<QMouseEvent*>(event)))
            return true;
        break;
    case QEvent::Leave:
        if (d->state != nullptr && d->state->dragging) {
#ifdef Q_OS_WIN
            // This is a workaround for losing the mouse on Vista.
            QPoint pos = QCursor::pos();
            QMouseEvent fake(QEvent::MouseMove, mapFromGlobal(pos), pos, Qt::NoButton,
                             QGuiApplication::mouseButtons(), QGuiApplication::keyboardModifiers());
            d->mouseMoveEvent(&fake);
#endif
        } else {
            if (!d->layout->expanded)
                break;
 
            QWidget *w = QApplication::activePopupWidget();
            if (waitForPopup(this, w)) {
                d->waitForPopupTimer.start(POPUP_TIMER_INTERVAL, this);
                break;
            }
 
            d->waitForPopupTimer.stop();
            d->layout->setExpanded(false);
            break;
        }
    default:
        break;
    }
    return QWidget::event(event);
}
 
QAction *QToolBar::toggleViewAction() const
{ Q_D(const QToolBar); return d->toggleViewAction; }
 
QWidget *QToolBar::widgetForAction(QAction *action) const
{
    Q_D(const QToolBar);
 
    int index = d->layout->indexOf(action);
    if (index == -1)
        return nullptr;
 
    return d->layout->itemAt(index)->widget();
}
 
extern QMainWindowLayout *qt_mainwindow_layout(const QMainWindow *window);
 
void QToolBar::initStyleOption(QStyleOptionToolBar *option) const
{
    Q_D(const QToolBar);
 
    if (!option)
        return;
 
    option->initFrom(this);
    if (orientation() == Qt::Horizontal)
        option->state |= QStyle::State_Horizontal;
    option->lineWidth = style()->pixelMetric(QStyle::PM_ToolBarFrameWidth, nullptr, this);
    option->features = d->layout->movable()
                        ? QStyleOptionToolBar::Movable
                        : QStyleOptionToolBar::None;
    // if the tool bar is not in a QMainWindow, this will make the painting right
    option->toolBarArea = Qt::NoToolBarArea;
 
    // Add more styleoptions if the toolbar has been added to a mainwindow.
    QMainWindow *mainWindow = qobject_cast<QMainWindow *>(parentWidget());
 
    if (!mainWindow)
        return;
 
    QMainWindowLayout *layout = qt_mainwindow_layout(mainWindow);
    Q_ASSERT_X(layout != nullptr, "QToolBar::initStyleOption()",
               "QMainWindow->layout() != QMainWindowLayout");
 
    layout->getStyleOptionInfo(option, const_cast<QToolBar *>(this));
}
 
QT_END_NAMESPACE
 
#include "moc_qtoolbar.cpp"