Another dojo example: web view with panning support

2 files changed, 137 insertions, 0 deletions

diff --git a/panwebview/panwebview.cpp b/panwebview/panwebview.cpp
new file mode 100644
index 0000000..2631133
--- /dev/null
+++ b/panwebview/panwebview.cpp
@@ -0,0 +1,133 @@
+/****************************************************************************
+**
+** Copyright (C) 2008-2008 Trolltech ASA. All rights reserved.
+**
+** This file is part of the Graphics Dojo project on Trolltech Labs.
+**
+** This file may be used under the terms of the GNU General Public
+** License version 2.0 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 GNU
+** General Public Licensing requirements will be met:
+** http://www.trolltech.com/products/qt/opensource.html
+**
+** If you are unsure which license is appropriate for your use, please
+** review the following information:
+** http://www.trolltech.com/products/qt/licensing.html or contact the
+** sales department at sales@trolltech.com.
+**
+** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+**
+****************************************************************************/
+
+#include <QtGui>
+#include <QtWebKit>
+
+class PanWebView : public QWebView
+{
+    Q_OBJECT
+
+private:
+    bool pressed;
+    bool scrolling;
+    QPoint position;
+    QPoint offset;
+    QList<QEvent*> ignored;
+
+public:
+    PanWebView(QWidget *parent = 0): QWebView(parent), pressed(false), scrolling(false) {
+        QWebFrame *frame = page()->mainFrame();
+        frame->setScrollBarPolicy(Qt::Vertical, Qt::ScrollBarAlwaysOff);
+        frame->setScrollBarPolicy(Qt::Horizontal, Qt::ScrollBarAlwaysOff);
+    }
+
+protected:
+
+    void mousePressEvent(QMouseEvent *mouseEvent) {
+
+        if (ignored.removeAll(mouseEvent))
+            return QWebView::mousePressEvent(mouseEvent);
+
+        if (!pressed && !scrolling && mouseEvent->modifiers() == Qt::NoModifier)
+            if (mouseEvent->buttons() == Qt::LeftButton) {
+                pressed = true;
+                scrolling = false;
+                position = mouseEvent->pos();
+                QWebFrame *frame = page()->mainFrame();
+                int x = frame->evaluateJavaScript("window.scrollX").toInt();
+                int y = frame->evaluateJavaScript("window.scrollY").toInt();
+                offset = QPoint(x, y);
+                QApplication::setOverrideCursor(Qt::OpenHandCursor);
+                return;
+            }
+
+        return QWebView::mousePressEvent(mouseEvent);
+    }
+
+    void mouseReleaseEvent(QMouseEvent *mouseEvent) {
+
+        if (ignored.removeAll(mouseEvent))
+            return QWebView::mouseReleaseEvent(mouseEvent);
+
+        if (scrolling) {
+            pressed = false;
+            scrolling = false;
+            QApplication::restoreOverrideCursor();
+            return;
+        }
+
+        if (pressed) {
+            pressed = false;
+            scrolling = false;
+
+            QMouseEvent *event1 = new QMouseEvent(QEvent::MouseButtonPress,
+                                                  position, Qt::LeftButton,
+                                                  Qt::LeftButton, Qt::NoModifier);
+            QMouseEvent *event2 = new QMouseEvent(*mouseEvent);
+
+            ignored << event1;
+            ignored << event2;
+            QApplication::postEvent(this, event1);
+            QApplication::postEvent(this, event2);
+            QApplication::restoreOverrideCursor();
+            return;
+        }
+
+        return QWebView::mouseReleaseEvent(mouseEvent);
+    }
+
+    void mouseMoveEvent(QMouseEvent *mouseEvent) {
+
+        if (scrolling) {
+            QPoint delta = mouseEvent->pos() - position;
+            QPoint p = offset - delta;
+            QWebFrame *frame = page()->mainFrame();
+            frame->evaluateJavaScript(QString("window.scrollTo(%1,%2);").arg(p.x()).arg(p.y()));
+            return;
+        }
+
+        if (pressed) {
+            pressed = false;
+            scrolling = true;
+            return;
+        }
+
+        return QWebView::mouseMoveEvent(mouseEvent);
+    }
+
+};
+
+#include "panwebview.moc"
+
+int main(int argc, char *argv[])
+{
+    QApplication app(argc, argv);
+
+    PanWebView web;
+    web.setUrl(QUrl("http://news.google.com"));
+    web.setWindowTitle("Web View - use mouse to drag and pan around");
+    web.show();
+
+    return app.exec();
+}
diff --git a/panwebview/panwebview.pro b/panwebview/panwebview.pro
new file mode 100644
index 0000000..0ec055e
--- /dev/null
+++ b/panwebview/panwebview.pro
@@ -0,0 +1,4 @@
+TEMPLATE = app
+TARGET = panwebview
+SOURCES = panwebview.cpp
+QT += network webkit