qmenu.cpp

奇趣公司比较新的qt/emd版本

    destroyed (as with any other QObject).

    \sa title
*/
QMenu::QMenu(const QString &title, QWidget *parent)
    : QWidget(*new QMenuPrivate, parent, Qt::Popup)
{
    Q_D(QMenu);
    d->init();
    d->menuAction->setText(title);
}

/*! \internal
 */
QMenu::QMenu(QMenuPrivate &dd, QWidget *parent)
    : QWidget(dd, parent, Qt::Popup)
{
    Q_D(QMenu);
    d->init();
}

/*!
    Destroys the menu.
*/
QMenu::~QMenu()
{
    Q_D(QMenu);
    if (d->eventLoop)
        d->eventLoop->exit();
    if (d->tornPopup)
        d->tornPopup->close();
}

/*!
    \overload

    This convenience function creates a new action with \a text.
    The function adds the newly created action to the menu's
    list of actions, and returns it.

    \sa QWidget::addAction()
*/
QAction *QMenu::addAction(const QString &text)
{
    QAction *ret = new QAction(text, this);
    addAction(ret);
    return ret;
}

/*!
    \overload

    This convenience function creates a new action with an \a icon
    and some \a text. The function adds the newly created action to
    the menu's list of actions, and returns it.

    \sa QWidget::addAction()
*/
QAction *QMenu::addAction(const QIcon &icon, const QString &text)
{
    QAction *ret = new QAction(icon, text, this);
    addAction(ret);
    return ret;
}

/*!
    \overload

    This convenience function creates a new action with the text \a
    text and an optional shortcut \a shortcut. The action's
    \l{QAction::triggered()}{triggered()} signal is connected to the
    \a receiver's \a member slot. The function adds the newly created
    action to the menu's list of actions and returns it.

    \sa QWidget::addAction()
*/
QAction *QMenu::addAction(const QString &text, const QObject *receiver, const char* member, const QKeySequence &shortcut)
{
    QAction *action = new QAction(text, this);
#ifdef QT_NO_SHORTCUT
    Q_UNUSED(shortcut);
#else
    action->setShortcut(shortcut);
#endif
    QObject::connect(action, SIGNAL(triggered(bool)), receiver, member);
    addAction(action);
    return action;
}

/*!
    \overload

    This convenience function creates a new action with an \a icon and
    some \a text and an optional shortcut \a shortcut. The action's
    \l{QAction::triggered()}{triggered()} signal is connected to the
    \a member slot of the \a receiver object. The function adds the
    newly created action to the menu's list of actions, and returns it.

    \sa QWidget::addAction()
*/
QAction *QMenu::addAction(const QIcon &icon, const QString &text, const QObject *receiver,
                          const char* member, const QKeySequence &shortcut)
{
    QAction *action = new QAction(icon, text, this);
#ifdef QT_NO_SHORTCUT
    Q_UNUSED(shortcut);
#else
    action->setShortcut(shortcut);
#endif
    QObject::connect(action, SIGNAL(triggered(bool)), receiver, member);
    addAction(action);
    return action;
}

/*!
    This convenience function adds \a menu as a submenu to this menu.
    It returns the menus menuAction().
    \sa QWidget::addAction() QMenu::menuAction()
*/
QAction *QMenu::addMenu(QMenu *menu)
{
    QAction *action = menu->menuAction();
    addAction(action);
    return action;
}

/*!
  Appends a new QMenu with \a title to the menu. The menu
  takes ownership of the menu. Returns the new menu.

  \sa QWidget::addAction() QMenu::menuAction()
*/
QMenu *QMenu::addMenu(const QString &title)
{
    QMenu *menu = new QMenu(title, this);
    addAction(menu->menuAction());
    return menu;
}

/*!
  Appends a new QMenu with \a icon and \a title to the menu. The menu
  takes ownership of the menu. Returns the new menu.

  \sa QWidget::addAction() QMenu::menuAction()
*/
QMenu *QMenu::addMenu(const QIcon &icon, const QString &title)
{
    QMenu *menu = new QMenu(title, this);
    menu->setIcon(icon);
    addAction(menu->menuAction());
    return menu;
}

/*!
    This convenience function creates a new separator action, i.e. an
    action with QAction::isSeparator() returning true, and adds the new
    action to this menu's list of actions. It returns the newly
    created action.

    \sa QWidget::addAction()
*/
QAction *QMenu::addSeparator()
{
    QAction *action = new QAction(this);
    action->setSeparator(true);
    addAction(action);
    return action;
}

/*!
    This convenience function inserts \a menu before action \a before
    and returns the menus menuAction().

    \sa QWidget::insertAction(), addMenu()
*/
QAction *QMenu::insertMenu(QAction *before, QMenu *menu)
{
    QAction *action = menu->menuAction();
    insertAction(before, action);
    return action;
}

/*!
    This convenience function creates a new separator action, i.e. an
    action with QAction::isSeparator() returning true. The function inserts
    the newly created action into this menu's list of actions before
    action \a before and returns it.

    \sa QWidget::insertAction(), addSeparator()
*/
QAction *QMenu::insertSeparator(QAction *before)
{
    QAction *action = new QAction(this);
    action->setSeparator(true);
    insertAction(before, action);
    return action;
}

/*!
  This will set the default action to \a act. The default action may
  have a visual queue depending on the current QStyle. A default
  action is usually meant to indicate what will defaultly happen on a
  drop, as shown in a context menu.

  \sa defaultAction()
*/
void QMenu::setDefaultAction(QAction *act)
{
    d_func()->defaultAction = act;
}

/*!
  Returns the current default action.

  \sa setDefaultAction()
*/
QAction *QMenu::defaultAction() const
{
    return d_func()->defaultAction;
}

/*!
    \property QMenu::tearOffEnabled
    \brief whether the menu supports being torn off

    When true, QMenu has a special menu item (often shown as a dashed
    line at the top of the menu) that creates a copy of the menu when
    the tear-off menu item is triggered. This "torn-off" copy lives in
    a separate window. It contains the same menu items as the original
    menu, with the exception of the tear-off handle.
*/
void QMenu::setTearOffEnabled(bool b)
{
    Q_D(QMenu);
    if (d->tearoff == b)
        return;
    if (!b && d->tornPopup)
        d->tornPopup->close();
    d->tearoff = b;

    d->itemsDirty = true;
    if (isVisible())
        resize(sizeHint());
}

bool QMenu::isTearOffEnabled() const
{
    return d_func()->tearoff;
}

/*!
  When a menu is torn off a second menu is shown to display the menu
  contents in a new window. When the menu is in this mode and the menu
  is visible returns true; otherwise false.

  \sa hideTearOffMenu() isTearOffEnabled()
*/
bool QMenu::isTearOffMenuVisible() const
{
    if (d_func()->tornPopup)
        return d_func()->tornPopup->isVisible();
    return false;
}

/*!
   This function will forcibly hide the torn off menu making it
   disappear from the users desktop.

   \sa isTearOffMenuVisible() isTearOffEnabled()
*/
void QMenu::hideTearOffMenu()
{
    if (d_func()->tornPopup)
        d_func()->tornPopup->close();
}


/*!
  Sets the currently highlighted action to \a act.
*/
void QMenu::setActiveAction(QAction *act)
{
    Q_D(QMenu);
    d->setCurrentAction(act, 0);
    if (d->scroll)
        d->scrollMenu(act, QMenuPrivate::QMenuScroller::ScrollCenter);
}


/*!
    Returns the currently highlighted action, or 0 if no
    action is currently highlighted.
*/
QAction *QMenu::activeAction() const
{
    return d_func()->currentAction;
}

/*!
    \since 4.2

    Returns true if there are no actions inserted into the menu, false
    otherwise.

    \sa QWidget::actions()
*/

bool QMenu::isEmpty() const
{
    return actions().isEmpty();
}

/*!
    Removes all the menu's actions. Actions owned by the menu and not
    shown in any other widget are deleted.

    \sa removeAction()
*/
void QMenu::clear()
{
    QList<QAction*> acts = actions();
    for(int i = 0; i < acts.size(); i++) {
        removeAction(acts[i]);
        if (acts[i]->parent() == this && acts[i]->d_func()->widgets.isEmpty())
            delete acts[i];
    }
}

/*!
  If a menu does not fit on the screen it lays itself out so that it
  does fit. It is style dependent what layout means (for example, on
  Windows it will use multiple columns).

  This functions returns the number of columns necessary.
*/
int QMenu::columnCount() const
{
    return d_func()->ncols;
}

/*!
  Returns the item at \a pt; returns 0 if there is no item there.
*/
QAction *QMenu::actionAt(const QPoint &pt) const
{
    if (QAction *ret = d_func()->actionAt(pt))
        return ret;
    return 0;
}

/*!
  Returns the geometry of action \a act.
*/
QRect QMenu::actionGeometry(QAction *act) const
{
    return d_func()->actionRect(act);
}

/*!
    \reimp
*/
QSize QMenu::sizeHint() const
{
    Q_D(const QMenu);
    ensurePolished();
    QMap<QAction*, QRect> actionRects;
    QList<QAction*> actionList;
    d->calcActionRects(actionRects, actionList);

    QSize s;
    QStyleOption opt(0);
    opt.rect = rect();
    opt.palette = palette();
    opt.state = QStyle::State_None;
    for (QMap<QAction*, QRect>::const_iterator i = actionRects.constBegin();
         i != actionRects.constEnd(); ++i) {
        if (i.value().bottom() > s.height())
            s.setHeight(i.value().y()+i.value().height());
        if (i.value().right() > s.width())
            s.setWidth(i.value().right());
    }
    if (d->tearoff)
        s.rheight() += style()->pixelMetric(QStyle::PM_MenuTearoffHeight, &opt, this);
    if (const int fw = style()->pixelMetric(QStyle::PM_MenuPanelWidth, &opt, this)) {
        s.rwidth() += fw*2;
        s.rheight() += fw*2;
    }
    s.rwidth() += 2 * style()->pixelMetric(QStyle::PM_MenuHMargin, &opt, this);
    s.rheight() += 2 * style()->pixelMetric(QStyle::PM_MenuVMargin, &opt, this);

    s += QSize(d->leftmargin + d->rightmargin, d->topmargin + d->bottommargin);

    return style()->sizeFromContents(QStyle::CT_Menu, &opt,
                                    s.expandedTo(QApplication::globalStrut()), this);