doc/src/snippets/signalsandslots/signalsandslots.cpp
author Eckhart Koeppen <eckhart.koppen@nokia.com>
Thu, 29 Apr 2010 15:15:16 +0300
branchRCL_3
changeset 16 4b6ee5efea19
parent 7 3f74d0d4af4c
permissions -rw-r--r--
2010-17 9996a03743ab23f83c83c5bc7ade0f82f71b1506

/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights.  These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QAbstractButton>

#include "signalsandslots.h"

//! [0]
void Counter::setValue(int value)
{
    if (value != m_value) {
        m_value = value;
        emit valueChanged(value);
    }
}
//! [0]

int main()
{
//! [1]
    Counter a, b;
//! [1] //! [2]
    QObject::connect(&a, SIGNAL(valueChanged(int)),
                     &b, SLOT(setValue(int)));
//! [2]

//! [3]
    a.setValue(12);     // a.value() == 12, b.value() == 12
//! [3] //! [4]
    b.setValue(48);     // a.value() == 12, b.value() == 48
//! [4]


    QWidget *widget = reinterpret_cast<QWidget *>(new QObject(0));
//! [5]
    if (widget->inherits("QAbstractButton")) {
        QAbstractButton *button = static_cast<QAbstractButton *>(widget);
        button->toggle();
//! [5] //! [6]
    }
//! [6]

//! [7]
    if (QAbstractButton *button = qobject_cast<QAbstractButton *>(widget))
        button->toggle();
//! [7]
}