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/****************************************************************************
**
** Copyright (C) 2015 The Qt Company Ltd.
** Contact: http://www.qt.io/licensing/
**
** This file is part of the documentation of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:FDL$
** 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 http://www.qt.io/terms-conditions. For further
** information use the contact form at http://www.qt.io/contact-us.
**
** GNU Free Documentation License Usage
** Alternatively, this file may be used under the terms of the GNU Free
** Documentation License version 1.3 as published by the Free Software
** Foundation and appearing in the file included in the packaging of
** this file. Please review the following information to ensure
** the GNU Free Documentation License version 1.3 requirements
** will be met: http://www.gnu.org/copyleft/fdl.html.
** $QT_END_LICENSE$
**
****************************************************************************/
/*!
\page qtwebengine-overview.html
\title Qt WebEngine Overview
The Qt WebEngine module provides a web browser engine that makes it easy to embed content from
the World Wide Web into your Qt application on platforms that do not have a native web engine.
The web engine is not intended to function as a \e {Web Runtime}; to display web content in a
QML application by using APIs native to the platform, use the \l{Qt WebView} module, instead.
Qt WebEngine provides C++ classes and QML types for rendering HTML, XHTML, and SVG documents,
styled using Cascading Style Sheets (CSS) and scripted with JavaScript. HTML documents can be
made fully editable by the user through the use of the \c{contenteditable} attribute on HTML
elements.
Qt WebEngine supercedes the \l{Qt WebKit Widgets}{Qt WebKit} module, which is based on the
WebKit project, but has not been actively synchronized with the upstream WebKit code since
Qt 5.2 and has been deprecated in Qt 5.5. For tips on how to change a Qt WebKit widgets
application to use Qt WebEngine widgets, see \l{Porting from Qt WebKit to Qt WebEngine}. For new
applications, we recommend using Qt Quick and the WebEngineView QML type.
\section1 Qt WebEngine Architecture
\image qtwebengine-architecture.png
The functionality in Qt WebEngine is divided into the following modules:
\list
\li \l{Qt WebEngine Widgets}, which provides a web browser engine and C++ classes to render
web content and to interact with it
\li \l{Qt WebEngine}, which provides QML types for rendering web content within a QML
application
\li \l{Qt WebEngine Core}, which provides common API used by Qt WebEngine and
Qt WebEngine Widgets
\endlist
The Qt WebEngine core is based on the \l{http://www.chromium.org}{Chromium Project}. Chromium
provides its own network and painting engines and is developed tightly together with its
dependent modules, and therefore Qt WebEngine provides better and more reliable support for the
latest HTML5 specification than Qt WebKit. However, Qt WebEngine is thus heavier than Qt WebKit
and does not provide direct access to the network stack and the HTML document through C++ APIs.
Chromium is tightly integrated to the \l{Qt Quick Scene Graph}{Qt Quick scene graph}, which is
based on OpenGL ES 2.0 or OpenGL 2.0 for its rendering. This provides you with one-pass
compositing of web content and all the Qt Quick UI. The integration to Chromium is transparent
to developers, who just work with Qt and JavaScript.
To expose QObjects to JavaScript, developers can use the \l {Qt WebChannel} module.
\section1 Embedding Web Content into Widget Based Applications
Use the QWebEngineView class to display web pages in the simplest way. Because it is a widget,
you can embed QWebEngineView into your forms and use its convenience functions to download and
display web sites.
\code
QWebEngineView *view = new QWebEngineView(parent);
view->load(QUrl("http://www.qt.io/"));
view->show();
\endcode
An instance of QWebEngineView has one QWebEnginePage. QWebEnginePage provides access to the
page's navigation history and the ability to run JavaScript code in the context of the page's
main frame and enables customization of handlers for specific events like showing custom
authentication dialogs.
\section1 Embedding Web Content into Qt Quick Applications
The WebEngineView QML type allows QML applications to render regions of dynamic web content. A
\e{WebEngineView} type may share the screen with other QML types or encompass the full screen
as specified within the QML application.
An application can load pages into the WebEngineView, using either an URL or HTML string, and
navigate within session history. By default, links to different pages load within the same
WebEngineView object, but web sites may request them to be opened as a new tab, window, or
dialog.
The following sample QML application loads a web page and responds to session history context:
\code
import QtQuick 2.1
import QtQuick.Controls 1.1
import QtWebEngine 1.1
ApplicationWindow {
width: 1280
height: 720
visible: true
WebEngineView {
id: webview
url: "http://www.qt.io"
anchors.fill: parent
}
}
\endcode
\section1 Using WebEngine Core
Qt WebEngine Core provides an API shared by Qt WebEngine and Qt WebEngine Widgets.
\section1 License Information
Qt WebEngine module is a snapshot of the integration of Chromium into Qt.
Qt Commercial Edition licensees that wish to distribute applications that
use the Qt WebEngine module need to be aware of their obligations under the
GNU Library General Public License (LGPLv2).
Developers using the Open Source Edition can choose to redistribute
the module under the GNU LGPLv3 or GPLv2 and up.
\legalese
Chromium is licensed under the following license:
Copyright (c) 2013 The Chromium Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
\endlegalese
*/
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