Add QtWebEngine backed help viewer backend

Supports most features. Defined priority for help viewers:
"qtwebkit" > "qtwebengine" > "textbrowser".

Task-number: QTCREATORBUG-13910
Change-Id: I59b4231ef93fdf9df46436850ed3743b5916f9cd
Reviewed-by: Nikita Baryshnikov <nib952051@gmail.com>
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

1 files changed, 103 insertions, 0 deletions

diff --git a/src/plugins/help/webenginehelpviewer.h b/src/plugins/help/webenginehelpviewer.h
new file mode 100644
index 0000000000..7d777ab487
--- /dev/null
+++ b/src/plugins/help/webenginehelpviewer.h
@@ -0,0 +1,103 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** 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 The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include "helpviewer.h"
+
+#include <QWebEngineUrlSchemeHandler>
+#include <QWebEngineView>
+
+namespace Help {
+namespace Internal {
+
+class HelpUrlSchemeHandler : public QWebEngineUrlSchemeHandler
+{
+public:
+    explicit HelpUrlSchemeHandler(QObject *parent = 0);
+    void requestStarted(QWebEngineUrlRequestJob *job) override;
+};
+
+class HelpPage : public QWebEnginePage
+{
+public:
+    explicit HelpPage(QObject *parent = 0);
+    QWebEnginePage *createWindow(QWebEnginePage::WebWindowType) override;
+};
+
+class WebView : public QWebEngineView
+{
+public:
+    explicit WebView(QWidget *parent = 0);
+
+    void setOpenInNewPageActionVisible(bool visible);
+
+protected:
+    void contextMenuEvent(QContextMenuEvent *event) override;
+
+private:
+    bool m_openInNewPageActionVisible = true;
+};
+
+class WebEngineHelpViewer : public HelpViewer
+{
+    Q_OBJECT
+public:
+    explicit WebEngineHelpViewer(QWidget *parent = 0);
+
+    QFont viewerFont() const override;
+    void setViewerFont(const QFont &font) override;
+    qreal scale() const override;
+    void setScale(qreal scale) override;
+    QString title() const override;
+    QUrl source() const override;
+    void setSource(const QUrl &url) override;
+    void setHtml(const QString &html) override;
+    QString selectedText() const override;
+    bool isForwardAvailable() const override;
+    bool isBackwardAvailable() const override;
+    void addBackHistoryItems(QMenu *backMenu) override;
+    void addForwardHistoryItems(QMenu *forwardMenu) override;
+    void setOpenInNewPageActionVisible(bool visible) override;
+    bool findText(const QString &text, Core::FindFlags flags, bool incremental, bool fromSearch, bool *wrapped) override;
+
+    HelpPage *page() const;
+
+public slots:
+    void scaleUp() override;
+    void scaleDown() override;
+    void resetScale() override;
+    void copy() override;
+    void stop() override;
+    void forward() override;
+    void backward() override;
+    void print(QPrinter *printer) override;
+
+private:
+    WebView *m_widget;
+};
+
+} // namespace Internal
+} // namespace Help