Long live Qt 4.5!

1 files changed, 94 insertions, 0 deletions

diff --git a/demos/browser/autosaver.cpp b/demos/browser/autosaver.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the demonstration applications 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 either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** 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 1.0, 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.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "autosaver.h"
+
+#include <QtCore/QDir>
+#include <QtCore/QCoreApplication>
+#include <QtCore/QMetaObject>
+#include <QtDebug>
+
+#define AUTOSAVE_IN  1000 * 3  // seconds
+#define MAXWAIT      1000 * 15 // seconds
+
+AutoSaver::AutoSaver(QObject *parent) : QObject(parent)
+{
+    Q_ASSERT(parent);
+}
+
+AutoSaver::~AutoSaver()
+{
+    if (m_timer.isActive())
+        qWarning() << "AutoSaver: still active when destroyed, changes not saved.";
+}
+
+void AutoSaver::changeOccurred()
+{
+    if (m_firstChange.isNull())
+        m_firstChange.start();
+
+    if (m_firstChange.elapsed() > MAXWAIT) {
+        saveIfNeccessary();
+    } else {
+        m_timer.start(AUTOSAVE_IN, this);
+    }
+}
+
+void AutoSaver::timerEvent(QTimerEvent *event)
+{
+    if (event->timerId() == m_timer.timerId()) {
+        saveIfNeccessary();
+    } else {
+        QObject::timerEvent(event);
+    }
+}
+
+void AutoSaver::saveIfNeccessary()
+{
+    if (!m_timer.isActive())
+        return;
+    m_timer.stop();
+    m_firstChange = QTime();
+    if (!QMetaObject::invokeMethod(parent(), "save", Qt::DirectConnection)) {
+        qWarning() << "AutoSaver: error invoking slot save() on parent";
+    }
+}
+