source: trunk/src/gui/kernel/qactiongroup.cpp@ 428

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#include "qactiongroup.h"

#ifndef QT_NO_ACTION

#include "qaction_p.h"
#include "qapplication.h"
#include "qevent.h"
#include "qlist.h"

QT_BEGIN_NAMESPACE

class QActionGroupPrivate : public QObjectPrivate
{
    Q_DECLARE_PUBLIC(QActionGroup)
public:
    QActionGroupPrivate() : exclusive(1), enabled(1), visible(1)  { }
    QList<QAction *> actions;
    QPointer<QAction> current;
    uint exclusive : 1;
    uint enabled : 1;
    uint visible : 1;

private:
    void _q_actionTriggered();  //private slot
    void _q_actionChanged();    //private slot
    void _q_actionHovered();    //private slot
};

void QActionGroupPrivate::_q_actionChanged()
{
    Q_Q(QActionGroup);
    QAction *action = qobject_cast<QAction*>(q->sender());
    Q_ASSERT_X(action != 0, "QWidgetGroup::_q_actionChanged", "internal error");
    if(exclusive && action->isChecked() && action != current) {
        if(current)
            current->setChecked(false);
        current = action;
    }
}

void QActionGroupPrivate::_q_actionTriggered()
{
    Q_Q(QActionGroup);
    QAction *action = qobject_cast<QAction*>(q->sender());
    Q_ASSERT_X(action != 0, "QWidgetGroup::_q_actionTriggered", "internal error");
    emit q->triggered(action);
    emit q->selected(action);
}

void QActionGroupPrivate::_q_actionHovered()
{
    Q_Q(QActionGroup);
    QAction *action = qobject_cast<QAction*>(q->sender());
    Q_ASSERT_X(action != 0, "QWidgetGroup::_q_actionHovered", "internal error");
    emit q->hovered(action);
}

/*!
    \class QActionGroup
    \brief The QActionGroup class groups actions together.

    \ingroup application

    In some situations it is useful to group actions together. For
    example, if you have a \gui{Left Align} action, a \gui{Right
    Align} action, a \gui{Justify} action, and a \gui{Center} action,
    only one of these actions should be active at any one time. One
    simple way of achieving this is to group the actions together in
    an action group.

    Here's a example (from the \l{mainwindows/menus}{Menus} example):

    \snippet examples/mainwindows/menus/mainwindow.cpp 6

    Here we create a new action group. Since the action group is
    exclusive by default, only one of the actions in the group is
    checked at any one time.

    \img qactiongroup-align.png Alignment options in a QMenu

    A QActionGroup emits an triggered() signal when one of its
    actions is chosen. Each action in an action group emits its
    triggered() signal as usual.

    As stated above, an action group is \l exclusive by default; it
    ensures that only one checkable action is active at any one time.
    If you want to group checkable actions without making them
    exclusive, you can turn of exclusiveness by calling
    setExclusive(false).

    Actions can be added to an action group using addAction(), but it
    is usually more convenient to specify a group when creating
    actions; this ensures that actions are automatically created with
    a parent. Actions can be visually separated from each other by
    adding a separator action to the group; create an action and use
    QAction's \l {QAction::}{setSeparator()} function to make it
    considered a separator. Action groups are added to widgets with
    the QWidget::addActions() function.

    \sa QAction
*/

/*!
    Constructs an action group for the \a parent object.

    The action group is exclusive by default. Call setExclusive(false)
    to make the action group non-exclusive.
*/
QActionGroup::QActionGroup(QObject* parent) : QObject(*new QActionGroupPrivate, parent)
{
}

/*!
    Destroys the action group.
*/
QActionGroup::~QActionGroup()
{
}

/*!
    \fn QAction *QActionGroup::addAction(QAction *action)

    Adds the \a action to this group, and returns it.

    Normally an action is added to a group by creating it with the
    group as its parent, so this function is not usually used.

    \sa QAction::setActionGroup()
*/
QAction *QActionGroup::addAction(QAction* a)
{
    Q_D(QActionGroup);
    if(!d->actions.contains(a)) {
        d->actions.append(a);
        QObject::connect(a, SIGNAL(triggered()), this, SLOT(_q_actionTriggered()));
        QObject::connect(a, SIGNAL(changed()), this, SLOT(_q_actionChanged()));
        QObject::connect(a, SIGNAL(hovered()), this, SLOT(_q_actionHovered()));
    }
    if(!a->d_func()->forceDisabled) {
        a->setEnabled(d->enabled);
        a->d_func()->forceDisabled = false;
    }
    if(!a->d_func()->forceInvisible) {
        a->setVisible(d->visible);
        a->d_func()->forceInvisible = false;
    }
    if(a->isChecked())
        d->current = a;
    QActionGroup *oldGroup = a->d_func()->group;
    if(oldGroup != this) {
        if (oldGroup)
            oldGroup->removeAction(a);
        a->d_func()->group = this;
    }
    return a;
}

/*!
    Creates and returns an action with \a text.  The newly created
    action is a child of this action group.

    Normally an action is added to a group by creating it with the
    group as parent, so this function is not usually used.

    \sa QAction::setActionGroup()
*/
QAction *QActionGroup::addAction(const QString &text)
{
    return new QAction(text, this);
}

/*!
    Creates and returns an action with \a text and an \a icon. The
    newly created action is a child of this action group.

    Normally an action is added to a group by creating it with the
    group as its parent, so this function is not usually used.

    \sa QAction::setActionGroup()
*/
QAction *QActionGroup::addAction(const QIcon &icon, const QString &text)