qaction.cpp

奇趣公司比较新的qt/emd版本

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#include "qaction.h"
#include "qactiongroup.h"

#ifndef QT_NO_ACTION
#include "qaction_p.h"
#include "qapplication.h"
#include "qevent.h"
#include "qlist.h"
#include "qdebug.h"
#include <private/qshortcutmap_p.h>
#include <private/qapplication_p.h>
#include <private/qmenu_p.h>

#define QAPP_CHECK(functionName) \
    if (!qApp) { \
        qWarning("QAction: Initialize QApplication before calling '" functionName "'."); \
        return; \
    }

/*
  internal: guesses a descriptive text from a text suited for a menu entry
 */
static QString qt_strippedText(QString s)
{
    s.remove( QString::fromLatin1("...") );
    int i = 0;
    while (i < s.size()) {
        ++i;
        if (s.at(i-1) != QLatin1Char('&'))
            continue;
        if (i < s.size() && s.at(i) == QLatin1Char('&'))
            ++i;
        s.remove(i-1,1);
    }
    return s.trimmed();
};


QActionPrivate::QActionPrivate() : group(0), enabled(1), forceDisabled(0),
                                   visible(1), forceInvisible(0), checkable(0), checked(0), separator(0), fontSet(false),
                                   menuRole(QAction::TextHeuristicRole)
{
#ifdef QT3_SUPPORT
    static int qt_static_action_id = -1;
    param = id = --qt_static_action_id;
    act_signal = 0;
#endif
#ifndef QT_NO_SHORTCUT
    shortcutId = 0;
    shortcutContext = Qt::WindowShortcut;
    autorepeat = true;
#endif
}

QActionPrivate::~QActionPrivate()
{
}

void QActionPrivate::sendDataChanged()
{
    Q_Q(QAction);
    QActionEvent e(QEvent::ActionChanged, q);
    for (int i = 0; i < widgets.size(); ++i) {
        QWidget *w = widgets.at(i);
        QApplication::sendEvent(w, &e);
    }
    QApplication::sendEvent(q, &e);

    emit q->changed();
}

#ifndef QT_NO_SHORTCUT
void QActionPrivate::redoGrab(QShortcutMap &map)
{
    Q_Q(QAction);
    if (shortcutId)
        map.removeShortcut(shortcutId, q);
    if (shortcut.isEmpty())
        return;
    shortcutId = map.addShortcut(q, shortcut, shortcutContext);
    if (!enabled)
        map.setShortcutEnabled(false, shortcutId, q);
    if (!autorepeat)
        map.setShortcutAutoRepeat(false, shortcutId, q);
}

void QActionPrivate::redoGrabAlternate(QShortcutMap &map)
{
    Q_Q(QAction);
    foreach (int id, alternateShortcutIds)
        if (id)
            map.removeShortcut(id, q);
    alternateShortcutIds.clear();
    if (alternateShortcuts.isEmpty())
        return;
    foreach (const QKeySequence& alternate, alternateShortcuts) {
        if (!alternate.isEmpty())
            alternateShortcutIds.append(map.addShortcut(q, alternate, shortcutContext));
        else
            alternateShortcutIds.append(0);
    }
    if (!enabled) {
        foreach (int id, alternateShortcutIds)
            map.setShortcutEnabled(false, id, q);
    }
    if (!autorepeat) {
        foreach (int id, alternateShortcutIds)
            map.setShortcutAutoRepeat(false, id, q);
    }
}

void QActionPrivate::setShortcutEnabled(bool enable, QShortcutMap &map)
{
    Q_Q(QAction);
    if (shortcutId)
        map.setShortcutEnabled(enable, shortcutId, q);
    foreach (int id, alternateShortcutIds)
        if (id)
            map.setShortcutEnabled(enable, id, q);
}
#endif // QT_NO_SHORTCUT

/*!
    \class QAction
    \brief The QAction class provides an abstract user interface
    action that can be inserted into widgets.

    \ingroup application
    \mainclass

    \omit
        * parent and widget are different
        * parent does not define context
    \endomit

    In applications many common commands can be invoked via menus,
    toolbar buttons, and keyboard shortcuts. Since the user expects
    each command to be performed in the same way, regardless of the
    user interface used, it is useful to represent each command as
    an \e action.

    Actions can be added to menus and toolbars, and will
    automatically keep them in sync. For example, in a word processor,
    if the user presses a Bold toolbar button, the Bold menu item
    will automatically be checked.

    Actions can be created as independent objects, but they may
    also be created during the construction of menus; the QMenu class
    contains convenience functions for creating actions suitable for
    use as menu items.

    A QAction may contain an icon, menu text, a shortcut, status text,
    "What's This?" text, and a tooltip. Most of these can be set in
    the constructor. They can also be set independently with
    setIcon(), setText(), setIconText(), setShortcut(),
    setStatusTip(), setWhatsThis(), and setToolTip(). For menu items,
    it is possible to set an individual font with setFont().

    Actions are added to widgets using QWidget::addAction(). Note
    that an action must be added to a widget before it can be used;
    this is also true when the shortcut should be global (i.e.,
    Qt::ApplicationShortcut as Qt::ShortcutContext).

    Once a QAction has been created it should be added to the relevant
    menu and toolbar, then connected to the slot which will perform
    the action. For example:

    \quotefile mainwindows/application/mainwindow.cpp
    \skipto openAct
    \printuntil connect
    \skipto fileMenu->addAction(openAct
    \printuntil fileMenu->addAction(openAct
    \skipto fileToolBar->addAction(openAct
    \printuntil fileToolBar->addAction(openAct

    We recommend that actions are created as children of the window
    they are used in. In most cases actions will be children of
    the application's main window.

    \sa QMenu, QToolBar, {Application Example}
*/

/*!
    \fn void QAction::trigger()

    This is a convenience slot that calls activate(Trigger).
*/

/*!
    \fn void QAction::hover()

    This is a convenience slot that calls activate(Hover).
*/

/*!
    \enum QAction::MenuRole

    This enum describes how an action should be moved into the application menu on Mac OS X.

    \value NoRole This action should not be put into the application menu
    \value TextHeuristicRole This action should be put in the application menu based on the action's text
           as described in the QMenuBar documentation.
    \value ApplicationSpecificRole This action should be put in the application menu with an application specific role
    \value AboutQtRole This action matches handles the "About Qt" menu item.
    \value AboutRole This action should be placed where the "About" menu item is in the application menu.
    \value PreferencesRole This action should be placed where the  "Preferences..." menu item is in the application menu.
    \value QuitRole This action should be placed where the Quit menu item is in the application menu.
*/

/*!
    Constructs an action with \a parent. If \a parent is an action
    group the action will be automatically inserted into the group.
*/
QAction::QAction(QObject* parent)
    : QObject(*(new QActionPrivate), parent)
{
    Q_D(QAction);
    d->group = qobject_cast<QActionGroup *>(parent);
    if (d->group)
        d->group->addAction(this);
}


/*!
    Constructs an action with some \a text and \a parent. If \a
    parent is an action group the action will be automatically
    inserted into the group.

    The action uses a stripped version of \a text (e.g. "\&Menu
    Option..." becomes "Menu Option") as descriptive text for
    tool buttons. You can override this by setting a specific
    description with setText(). The same text will be used for
    tooltips unless you specify a different text using
    setToolTip().

*/
QAction::QAction(const QString &text, QObject* parent)
    : QObject(*(new QActionPrivate), parent)
{
    Q_D(QAction);
    d->text = text;
    d->group = qobject_cast<QActionGroup *>(parent);
    if (d->group)
        d->group->addAction(this);
}

/*!
    Constructs an action with an \a icon and some \a text and \a
    parent. If \a parent is an action group the action will be
    automatically inserted into the group.

    The action uses a stripped version of \a text (e.g. "\&Menu
    Option..." becomes "Menu Option") as descriptive text for
    tool buttons. You can override this by setting a specific
    description with setText(). The same text will be used for
    tooltips unless you specify a different text using
    setToolTip().
*/
QAction::QAction(const QIcon &icon, const QString &text, QObject* parent)
    : QObject(*(new QActionPrivate), parent)
{
    Q_D(QAction);
    d->icon = icon;
    d->text = text;
    d->group = qobject_cast<QActionGroup *>(parent);
    if (d->group)
        d->group->addAction(this);
}

/*!
    \internal
*/
QAction::QAction(QActionPrivate &dd, QObject *parent)
    : QObject(dd, parent)
{
    Q_D(QAction);
    d->group = qobject_cast<QActionGroup *>(parent);
    if (d->group)
        d->group->addAction(this);
}

/*!
    Returns the parent widget.
*/
QWidget *QAction::parentWidget() const
{
    QObject *ret = parent();
    while (ret && !ret->isWidgetType())
        ret = ret->parent();
    return (QWidget*)ret;
}

/*!
  \since 4.2
  Returns a list of widgets this action has been added to.

  \sa QWidget::addAction()
*/
QList<QWidget *> QAction::associatedWidgets() const
{
    Q_D(const QAction);
    return d->widgets;
}

#ifndef QT_NO_SHORTCUT
/*!
    \property QAction::shortcut
    \brief the action's primary shortcut key

    Valid keycodes for this property can be found in \l Qt::Key and
    \l Qt::Modifier. There is no default shortcut key.
*/
void QAction::setShortcut(const QKeySequence &shortcut)
{
    QAPP_CHECK("setShortcut");

    Q_D(QAction);
    if (d->shortcut == shortcut)
        return;

    d->shortcut = shortcut;
    d->redoGrab(qApp->d_func()->shortcutMap);
    d->sendDataChanged();
}

/*!
    \since 4.2

    Sets \a shortcuts as the list of shortcuts that trigger the
    action. The first element of the list is the primary shortcut.

    \sa shortcut
*/
void QAction::setShortcuts(const QList<QKeySequence> &shortcuts)
{
    Q_D(QAction);

    QList <QKeySequence> listCopy = shortcuts;

    QKeySequence primary;
    if (!listCopy.isEmpty())
        primary = listCopy.takeFirst();

    if (d->shortcut == primary && d->alternateShortcuts == listCopy)
        return;

    QAPP_CHECK("setShortcuts");

    d->shortcut = primary;
    d->alternateShortcuts = listCopy;
    d->redoGrab(qApp->d_func()->shortcutMap);
    d->redoGrabAlternate(qApp->d_func()->shortcutMap);
    d->sendDataChanged();
}

/*!
    \since 4.2

    Sets a platform dependent list of shortcuts based on the \a key.
    The result of calling this function will depend on the currently running platform.
    Note that more than one shortcut can assigned by this action.
    If only the primary shortcut is required, use setShortcut instead.

    \sa QKeySequence::keyBindings()
*/
void QAction::setShortcuts(QKeySequence::StandardKey key)
{
    QList <QKeySequence> list = QKeySequence::keyBindings(key);
    setShortcuts(list);
}

/*!
    Returns the primary shortcut.

    \sa setShortcuts()
*/
QKeySequence QAction::shortcut() const
{
    Q_D(const QAction);
    return d->shortcut;
}

/*!
    \since 4.2

    Returns the list of shortcuts, with the primary shortcut as
    the first element of the list.

    \sa setShortcuts()
*/
QList<QKeySequence> QAction::shortcuts() const
{
    Q_D(const QAction);
    QList <QKeySequence> shortcuts;
    if (!d->shortcut.isEmpty())
        shortcuts << d->shortcut;
    if (!d->alternateShortcuts.isEmpty())
        shortcuts << d->alternateShortcuts;
    return shortcuts;
}