--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/demos/embedded/anomaly/src/flickcharm.cpp Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,335 @@
+/****************************************************************************
+**
+** 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 demos 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 "flickcharm.h"
+
+#include <QAbstractScrollArea>
+#include <QApplication>
+#include <QBasicTimer>
+#include <QEvent>
+#include <QHash>
+#include <QList>
+#include <QMouseEvent>
+#include <QScrollBar>
+#include <QWebFrame>
+#include <QWebView>
+
+#include <QDebug>
+
+struct FlickData {
+ typedef enum { Steady, Pressed, ManualScroll, AutoScroll, Stop } State;
+ State state;
+ QWidget *widget;
+ QPoint pressPos;
+ QPoint offset;
+ QPoint dragPos;
+ QPoint speed;
+ QList<QEvent*> ignored;
+};
+
+class FlickCharmPrivate
+{
+public:
+ QHash<QWidget*, FlickData*> flickData;
+ QBasicTimer ticker;
+};
+
+FlickCharm::FlickCharm(QObject *parent): QObject(parent)
+{
+ d = new FlickCharmPrivate;
+}
+
+FlickCharm::~FlickCharm()
+{
+ delete d;
+}
+
+void FlickCharm::activateOn(QWidget *widget)
+{
+ QAbstractScrollArea *scrollArea = qobject_cast<QAbstractScrollArea*>(widget);
+ if (scrollArea) {
+ scrollArea->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+ scrollArea->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+
+ QWidget *viewport = scrollArea->viewport();
+
+ viewport->installEventFilter(this);
+ scrollArea->installEventFilter(this);
+
+ d->flickData.remove(viewport);
+ d->flickData[viewport] = new FlickData;
+ d->flickData[viewport]->widget = widget;
+ d->flickData[viewport]->state = FlickData::Steady;
+
+ return;
+ }
+
+ QWebView *webView = qobject_cast<QWebView*>(widget);
+ if (webView) {
+ QWebFrame *frame = webView->page()->mainFrame();
+ frame->setScrollBarPolicy(Qt::Vertical, Qt::ScrollBarAlwaysOff);
+ frame->setScrollBarPolicy(Qt::Horizontal, Qt::ScrollBarAlwaysOff);
+
+ webView->installEventFilter(this);
+
+ d->flickData.remove(webView);
+ d->flickData[webView] = new FlickData;
+ d->flickData[webView]->widget = webView;
+ d->flickData[webView]->state = FlickData::Steady;
+
+ return;
+ }
+
+ qWarning() << "FlickCharm only works on QAbstractScrollArea (and derived classes)";
+ qWarning() << "or QWebView (and derived classes)";
+}
+
+void FlickCharm::deactivateFrom(QWidget *widget)
+{
+ QAbstractScrollArea *scrollArea = qobject_cast<QAbstractScrollArea*>(widget);
+ if (scrollArea) {
+ QWidget *viewport = scrollArea->viewport();
+
+ viewport->removeEventFilter(this);
+ scrollArea->removeEventFilter(this);
+
+ delete d->flickData[viewport];
+ d->flickData.remove(viewport);
+
+ return;
+ }
+
+ QWebView *webView = qobject_cast<QWebView*>(widget);
+ if (webView) {
+ webView->removeEventFilter(this);
+
+ delete d->flickData[webView];
+ d->flickData.remove(webView);
+
+ return;
+ }
+}
+
+static QPoint scrollOffset(QWidget *widget)
+{
+ int x = 0, y = 0;
+
+ QAbstractScrollArea *scrollArea = qobject_cast<QAbstractScrollArea*>(widget);
+ if (scrollArea) {
+ x = scrollArea->horizontalScrollBar()->value();
+ y = scrollArea->verticalScrollBar()->value();
+ }
+
+ QWebView *webView = qobject_cast<QWebView*>(widget);
+ if (webView) {
+ QWebFrame *frame = webView->page()->mainFrame();
+ x = frame->evaluateJavaScript("window.scrollX").toInt();
+ y = frame->evaluateJavaScript("window.scrollY").toInt();
+ }
+
+ return QPoint(x, y);
+}
+
+static void setScrollOffset(QWidget *widget, const QPoint &p)
+{
+ QAbstractScrollArea *scrollArea = qobject_cast<QAbstractScrollArea*>(widget);
+ if (scrollArea) {
+ scrollArea->horizontalScrollBar()->setValue(p.x());
+ scrollArea->verticalScrollBar()->setValue(p.y());
+ }
+
+ QWebView *webView = qobject_cast<QWebView*>(widget);
+ QWebFrame *frame = webView ? webView->page()->mainFrame() : 0;
+ if (frame)
+ frame->evaluateJavaScript(QString("window.scrollTo(%1,%2);").arg(p.x()).arg(p.y()));
+}
+
+static QPoint deaccelerate(const QPoint &speed, int a = 1, int max = 64)
+{
+ int x = qBound(-max, speed.x(), max);
+ int y = qBound(-max, speed.y(), max);
+ x = (x == 0) ? x : (x > 0) ? qMax(0, x - a) : qMin(0, x + a);
+ y = (y == 0) ? y : (y > 0) ? qMax(0, y - a) : qMin(0, y + a);
+ return QPoint(x, y);
+}
+
+bool FlickCharm::eventFilter(QObject *object, QEvent *event)
+{
+ if (!object->isWidgetType())
+ return false;
+
+ QEvent::Type type = event->type();
+ if (type != QEvent::MouseButtonPress &&
+ type != QEvent::MouseButtonRelease &&
+ type != QEvent::MouseMove)
+ return false;
+
+ QMouseEvent *mouseEvent = 0;
+ switch (event->type()) {
+ case QEvent::MouseButtonPress:
+ case QEvent::MouseButtonRelease:
+ case QEvent::MouseMove:
+ mouseEvent = static_cast<QMouseEvent*>(event);
+ break;
+ }
+
+ if (!mouseEvent || mouseEvent->modifiers() != Qt::NoModifier)
+ return false;
+
+ QWidget *viewport = qobject_cast<QWidget*>(object);
+ FlickData *data = d->flickData.value(viewport);
+ if (!viewport || !data || data->ignored.removeAll(event))
+ return false;
+
+ bool consumed = false;
+ switch (data->state) {
+
+ case FlickData::Steady:
+ if (mouseEvent->type() == QEvent::MouseButtonPress)
+ if (mouseEvent->buttons() == Qt::LeftButton) {
+ consumed = true;
+ data->state = FlickData::Pressed;
+ data->pressPos = mouseEvent->pos();
+ data->offset = scrollOffset(data->widget);
+ }
+ break;
+
+ case FlickData::Pressed:
+ if (mouseEvent->type() == QEvent::MouseButtonRelease) {
+ consumed = true;
+ data->state = FlickData::Steady;
+
+ QMouseEvent *event1 = new QMouseEvent(QEvent::MouseButtonPress,
+ data->pressPos, Qt::LeftButton,
+ Qt::LeftButton, Qt::NoModifier);
+ QMouseEvent *event2 = new QMouseEvent(*mouseEvent);
+
+ data->ignored << event1;
+ data->ignored << event2;
+ QApplication::postEvent(object, event1);
+ QApplication::postEvent(object, event2);
+ }
+ if (mouseEvent->type() == QEvent::MouseMove) {
+ consumed = true;
+ data->state = FlickData::ManualScroll;
+ data->dragPos = QCursor::pos();
+ if (!d->ticker.isActive())
+ d->ticker.start(20, this);
+ }
+ break;
+
+ case FlickData::ManualScroll:
+ if (mouseEvent->type() == QEvent::MouseMove) {
+ consumed = true;
+ QPoint delta = mouseEvent->pos() - data->pressPos;
+ setScrollOffset(data->widget, data->offset - delta);
+ }
+ if (mouseEvent->type() == QEvent::MouseButtonRelease) {
+ consumed = true;
+ data->state = FlickData::AutoScroll;
+ }
+ break;
+
+ case FlickData::AutoScroll:
+ if (mouseEvent->type() == QEvent::MouseButtonPress) {
+ consumed = true;
+ data->state = FlickData::Stop;
+ data->speed = QPoint(0, 0);
+ data->pressPos = mouseEvent->pos();
+ data->offset = scrollOffset(data->widget);
+ }
+ if (mouseEvent->type() == QEvent::MouseButtonRelease) {
+ consumed = true;
+ data->state = FlickData::Steady;
+ data->speed = QPoint(0, 0);
+ }
+ break;
+
+ case FlickData::Stop:
+ if (mouseEvent->type() == QEvent::MouseButtonRelease) {
+ consumed = true;
+ data->state = FlickData::Steady;
+ }
+ if (mouseEvent->type() == QEvent::MouseMove) {
+ consumed = true;
+ data->state = FlickData::ManualScroll;
+ data->dragPos = QCursor::pos();
+ if (!d->ticker.isActive())
+ d->ticker.start(20, this);
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ return consumed;
+}
+
+void FlickCharm::timerEvent(QTimerEvent *event)
+{
+ int count = 0;
+ QHashIterator<QWidget*, FlickData*> item(d->flickData);
+ while (item.hasNext()) {
+ item.next();
+ FlickData *data = item.value();
+
+ if (data->state == FlickData::ManualScroll) {
+ count++;
+ data->speed = QCursor::pos() - data->dragPos;
+ data->dragPos = QCursor::pos();
+ }
+
+ if (data->state == FlickData::AutoScroll) {
+ count++;
+ data->speed = deaccelerate(data->speed);
+ QPoint p = scrollOffset(data->widget);
+ setScrollOffset(data->widget, p - data->speed);
+ if (data->speed == QPoint(0, 0))
+ data->state = FlickData::Steady;
+ }
+ }
+
+ if (!count)
+ d->ticker.stop();
+
+ QObject::timerEvent(event);
+}