demos/browser/chasewidget.cpp
changeset 0 1918ee327afb
child 4 3b1da2848fc7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/demos/browser/chasewidget.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,142 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (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 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 "chasewidget.h"
+
+#include <QtCore/QPoint>
+
+#include <QtGui/QApplication>
+#include <QtGui/QHideEvent>
+#include <QtGui/QPainter>
+#include <QtGui/QPaintEvent>
+#include <QtGui/QShowEvent>
+
+ChaseWidget::ChaseWidget(QWidget *parent, QPixmap pixmap, bool pixmapEnabled)
+    : QWidget(parent)
+    , m_segment(0)
+    , m_delay(100)
+    , m_step(40)
+    , m_timerId(-1)
+    , m_animated(false)
+    , m_pixmap(pixmap)
+    , m_pixmapEnabled(pixmapEnabled)
+{
+}
+
+void ChaseWidget::setAnimated(bool value)
+{
+    if (m_animated == value)
+        return;
+    m_animated = value;
+    if (m_timerId != -1) {
+        killTimer(m_timerId);
+        m_timerId = -1;
+    }
+    if (m_animated) {
+        m_segment = 0;
+        m_timerId = startTimer(m_delay);
+    }
+    update();
+}
+
+void ChaseWidget::paintEvent(QPaintEvent *event)
+{
+    Q_UNUSED(event);
+    QPainter p(this);
+    if (m_pixmapEnabled && !m_pixmap.isNull()) {
+        p.drawPixmap(0, 0, m_pixmap);
+        return;
+    }
+
+    const int extent = qMin(width() - 8, height() - 8);
+    const int displ = extent / 4;
+    const int ext = extent / 4 - 1;
+
+    p.setRenderHint(QPainter::Antialiasing, true);
+
+    if(m_animated)
+        p.setPen(Qt::gray);
+    else
+        p.setPen(QPen(palette().dark().color()));
+
+    p.translate(width() / 2, height() / 2); // center
+
+    for (int segment = 0; segment < segmentCount(); ++segment) {
+        p.rotate(QApplication::isRightToLeft() ? m_step : -m_step);
+        if(m_animated)
+            p.setBrush(colorForSegment(segment));
+        else
+            p.setBrush(palette().background());
+        p.drawEllipse(QRect(displ, -ext / 2, ext, ext));
+    }
+}
+
+QSize ChaseWidget::sizeHint() const
+{
+    return QSize(32, 32);
+}
+
+void ChaseWidget::timerEvent(QTimerEvent *event)
+{
+    if (event->timerId() == m_timerId) {
+        ++m_segment;
+        update();
+    }
+    QWidget::timerEvent(event);
+}
+
+QColor ChaseWidget::colorForSegment(int seg) const
+{
+    int index = ((seg + m_segment) % segmentCount());
+    int comp = qMax(0, 255 - (index * (255 / segmentCount())));
+    return QColor(comp, comp, comp, 255);
+}
+
+int ChaseWidget::segmentCount() const
+{
+    return 360 / m_step;
+}
+
+void ChaseWidget::setPixmapEnabled(bool enable)
+{
+    m_pixmapEnabled = enable;
+}
+