Implement a common interface for help viewers.

Both implementations are now split into two source files, based on the
base class type. They share also a commen implementation, but the class
interface looks now clean to the outside. Adopt other classes for use.

src/plugins/help/helpviewer.h

@@ -0,0 +1,135 @@
+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** 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.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+
+#ifndef HELPVIEWER_H
+#define HELPVIEWER_H
+
+#include <find/ifindsupport.h>
+
+#include <QtCore/qglobal.h>
+#include <QtCore/QString>
+#include <QtCore/QUrl>
+#include <QtCore/QVariant>
+
+#include <QtGui/QAction>
+#include <QtGui/QFont>
+
+#if defined(QT_NO_WEBKIT)
+#include <QtGui/QTextBrowser>
+#else
+#include <QtWebKit/QWebView>
+#endif
+
+namespace Help {
+    namespace Internal {
+
+#if !defined(QT_NO_WEBKIT)
+class HelpViewer : public QWebView
+#else
+class HelpViewer : public QTextBrowser
+#endif
+{
+    Q_OBJECT
+    class HelpViewerPrivate;
+    Q_DISABLE_COPY(HelpViewer)
+
+public:
+    HelpViewer(qreal zoom, QWidget *parent = 0);
+    ~HelpViewer();
+
+    QFont viewerFont() const;
+    void setViewerFont(const QFont &font);
+
+    void scaleUp();
+    void scaleDown();
+
+    void resetScale();
+    qreal scale() const;
+
+    QString title() const;
+    void setTitle(const QString &title);
+
+    QUrl source() const;
+    void setSource(const QUrl &url);
+
+    QString selectedText() const;
+    bool isForwardAvailable() const;
+    bool isBackwardAvailable() const;
+
+    bool findText(const QString &text, Find::IFindSupport::FindFlags flags,
+        bool incremental);
+
+    static QString AboutBlankPage;
+    static QString PageNotFoundMessage;
+
+    static bool isLocalUrl(const QUrl &url);
+    static bool canOpenPage(const QString &url);
+    static bool launchWithExternalApp(const QUrl &url);
+
+public slots:
+    void copy();
+    void home();
+
+    void forward();
+    void backward();
+
+signals:
+    void titleChanged();
+#if !defined(QT_NO_WEBKIT)
+    void sourceChanged(const QUrl &);
+    void forwardAvailable(bool enabled);
+    void backwardAvailable(bool enabled);
+#else
+    void loadFinished(bool finished);
+#endif
+
+protected:
+    void keyPressEvent(QKeyEvent *e);
+    void wheelEvent(QWheelEvent *event);
+    void mousePressEvent(QMouseEvent *event);
+    void mouseReleaseEvent(QMouseEvent *event);
+
+private slots:
+    void actionChanged();
+    void setLoadFinished(bool ok);
+
+private:
+    bool eventFilter(QObject *obj, QEvent *event);
+    void contextMenuEvent(QContextMenuEvent *event);
+    QVariant loadResource(int type, const QUrl &name);
+    bool handleForwardBackwardMouseButtons(QMouseEvent *e);
+
+private:
+    HelpViewerPrivate *d;
+};
+
+    }   // namespace Help
+}   // namespace Internal
+
+#endif  // HELPVIEWER_H