qt5base-lts/examples/gui/rasterwindow/rasterwindow.cpp
Jani Heikkinen 2b75c156b6 Updated BSD licensed file headers
Change-Id: I6441ff931dbd33b698d762e6f6784898f3f60fe7
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
2015-02-15 07:41:17 +00:00

125 lines
3.4 KiB
C++

/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** 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 The Qt Company Ltd 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]