Introduce (private) QStyleAnimation

QStyleAnimation handles style animations in a generic fashion by
sending StyleAnimationUpdate events back to the animation target
instead of calling QWidget::update() directly. This decouples style
animations from widgets and makes it possible to run style animations
for QQuickItems (ie. the desktop components).

The next step is to add "QObject* QStyleOption::target" and use that
everywhere instead of the widget pointer passed to various QStyle
methods.

Change-Id: Ib963c54872805fc3f0123ff922f82c9962a68b90
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>

1 files changed, 148 insertions, 0 deletions

diff --git a/src/widgets/styles/qstyleanimation.cpp b/src/widgets/styles/qstyleanimation.cpp
new file mode 100644
index 0000000000..8bc8e9d241
--- /dev/null
+++ b/src/widgets/styles/qstyleanimation.cpp
@@ -0,0 +1,148 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the QtGui module 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 "qstyleanimation_p.h"
+#include <qcoreapplication.h>
+#include <qprogressbar.h>
+#include <qwidget.h>
+#include <qevent.h>
+
+QT_BEGIN_NAMESPACE
+
+#ifndef QT_NO_ANIMATION
+
+QStyleAnimation::QStyleAnimation(QObject *target) : QAbstractAnimation(target),
+    _startTime(QTime::currentTime())
+{
+}
+
+QStyleAnimation::~QStyleAnimation()
+{
+}
+
+int QStyleAnimation::duration() const
+{
+    return -1;
+}
+
+QObject *QStyleAnimation::target() const
+{
+    return parent();
+}
+
+QTime QStyleAnimation::startTime() const
+{
+    return _startTime;
+}
+
+void QStyleAnimation::setStartTime(const QTime &time)
+{
+    _startTime = time;
+}
+
+bool QStyleAnimation::isUpdateNeeded() const
+{
+    return true;
+}
+
+void QStyleAnimation::updateCurrentTime(int)
+{
+    if (target()->isWidgetType()) {
+        QWidget *widget = static_cast<QWidget *>(target());
+        if (!widget->isVisible() || widget->window()->isMinimized())
+            stop();
+    }
+
+    if (isUpdateNeeded()) {
+        QEvent event(QEvent::StyleAnimationUpdate);
+        QCoreApplication::sendEvent(target(), &event);
+    }
+}
+
+QProgressStyleAnimation::QProgressStyleAnimation(int speed, QObject *target) :
+    QStyleAnimation(target), _speed(speed), _step(-1)
+{
+}
+
+int QProgressStyleAnimation::animationStep() const
+{
+    return currentTime() / (1000.0 / _speed);
+}
+
+int QProgressStyleAnimation::progressStep(int width) const
+{
+    int step = animationStep();
+    int progress = (step * width / _speed) % width;
+    if (((step * width / _speed) % (2 * width)) >= width)
+        progress = width - progress;
+    return progress;
+}
+
+int QProgressStyleAnimation::speed() const
+{
+    return _speed;
+}
+
+void QProgressStyleAnimation::setSpeed(int speed)
+{
+    _speed = speed;
+}
+
+bool QProgressStyleAnimation::isUpdateNeeded() const
+{
+    QProgressBar *pb = qobject_cast<QProgressBar*>(parent());
+    if (pb && pb->minimum() == 0 && pb->maximum() == 0) {
+        int current = animationStep();
+        if (_step == -1 || _step != current)
+        {
+            _step = current;
+            return true;
+        }
+    } else {
+        // the progress bar is no longer indeterminate -> stop
+        const_cast<QProgressStyleAnimation *>(this)->stop();
+    }
+    return false;
+}
+
+#endif // QT_NO_ANIMATION
+
+QT_END_NAMESPACE