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/****************************************************************************
**
** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/legal
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and Digia. For licensing terms and
** conditions see http://qt.digia.com/licensing. For further information
** use the contact form at http://qt.digia.com/contact-us.
**
** 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, Digia gives you certain additional
** rights. These rights are described in the Digia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file. Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
** met: http://www.gnu.org/copyleft/gpl.html.
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#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]
}
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