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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 examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**   * Redistributions of source code must retain the above copyright
**     notice, this list of conditions and the following disclaimer.
**   * Redistributions in binary form must reproduce the above copyright
**     notice, this list of conditions and the following disclaimer in
**     the documentation and/or other materials provided with the
**     distribution.
**   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
**     of its contributors may be used to endorse or promote products derived
**     from this software without specific prior written permission.
**
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "rasterwindow.h"

//! [1]
RasterWindow::RasterWindow(QWindow *parent)
    : QWindow(parent)
    , m_update_pending(false)
{
    m_backingStore = new QBackingStore(this);
    create();

    setGeometry(100, 100, 300, 200);

}
//! [1]


//! [7]
bool RasterWindow::event(QEvent *event)
{
    if (event->type() == QEvent::UpdateRequest) {
        m_update_pending = false;
        renderNow();
        return true;
    }
    return QWindow::event(event);
}
//! [7]

//! [6]
void RasterWindow::renderLater()
{
    if (!m_update_pending) {
        m_update_pending = true;
        QCoreApplication::postEvent(this, new QEvent(QEvent::UpdateRequest));
    }
}
//! [6]


//! [5]
void RasterWindow::resizeEvent(QResizeEvent *resizeEvent)
{
    m_backingStore->resize(resizeEvent->size());
    if (isExposed())
        renderNow();
}
//! [5]

//! [2]
void RasterWindow::exposeEvent(QExposeEvent *)
{
    if (isExposed()) {
        renderNow();
    }
}
//! [2]


//! [3]
void RasterWindow::renderNow()
{
    if (!isExposed())
        return;

    QRect rect(0, 0, width(), height());
    m_backingStore->beginPaint(rect);

    QPaintDevice *device = m_backingStore->paintDevice();
    QPainter painter(device);

    painter.fillRect(0, 0, width(), height(), Qt::white);
    render(&painter);

    m_backingStore->endPaint();
    m_backingStore->flush(rect);
}
//! [3]

//! [4]
void RasterWindow::render(QPainter *painter)
{
    painter->drawText(QRectF(0, 0, width(), height()), Qt::AlignCenter, QStringLiteral("QWindow"));
}
//! [4]