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diff --git a/src/webengine/doc/src/qtwebengine-overview.qdoc b/src/webengine/doc/src/qtwebengine-overview.qdoc deleted file mode 100644 index 1c30f9858..000000000 --- a/src/webengine/doc/src/qtwebengine-overview.qdoc +++ /dev/null @@ -1,315 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2017 The Qt Company Ltd. -** Contact: https://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 https://www.qt.io/terms-conditions. For further -** information use the contact form at https://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: https://www.gnu.org/licenses/fdl-1.3.html. -** $QT_END_LICENSE$ -** -****************************************************************************/ - -/*! - \page qtwebengine-overview.html - \title Qt WebEngine Overview - - The \QWE 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. - - \QWE 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. - - \section1 Qt WebEngine Architecture - - \image qtwebengine-architecture.png - - The functionality in \QWE is divided into the following modules: - - \list - \li \l{Qt WebEngine Widgets Module} for creating widget-based web applications - \li \l{Qt WebEngine Module} for creating Qt Quick based web applications - \li \l{Qt WebEngine Core Module} for interacting with Chromium - \endlist - - Page rendering and JavaScript execution are separated from the GUI process into the \QWE - Process. It is a library that must be shipped with the application if the Qt libraries are - bundled into the application. - - \section2 Qt WebEngine Widgets Module - - \image qtwebenginewidgets-model.png - - A \e {web engine view} is the main widget component of the \QWE module. It can be used - in various applications to load web content. Within a view, a \e {web engine page} holds a main - frame that is responsible for web content, the \e history of navigated links, and \e actions. - The view and page are quite similar, as they provide a set of common functions. - - All pages belong to a \e {web engine profile} that contains shared \e settings, \e scripts, and - \e cookies. Profiles can be used to isolate pages from each other. A typical use case is a - dedicated profile for a \e {private browsing} mode, where no information is permanently saved. - - \note The \QWE Widgets module uses the \l{Qt Quick Scene Graph}{Qt Quick scene graph} - to compose the elements of a web page into one view. This means that the UI process - requires OpenGL ES 2.0 or OpenGL 2.0 for its rendering. - - \section2 Qt WebEngine Module - - \image qtwebengine-model.png - - The \QWE QML implementation contains the same elements as the \QWE Widgets - implementation, except that there is no separately accessible web engine page. - The supported page functionality is integrated into the web engine view. - - \section2 Qt WebEngine Core Module - - The \QWE core is based on the \l {Chromium Project}. Chromium provides its own network - and painting engines and is developed tightly together with its dependent modules. - - \note \QWE is based on Chromium, but does not contain or use any services - or add-ons that might be part of the Chrome browser that is built and delivered by Google. - You can find more detailed information about the differences between Chromium and Chrome in this - \l{https://chromium.googlesource.com/chromium/src/+/master/docs/chromium_browser_vs_google_chrome.md}{overview} - that is part of the documentation in the \l {Chromium Project} upstream source tree. - - This version of \QWE is based on Chromium version 80.0.3987, with additional security - fixes from newer versions. - - \section2 Qt WebEngine Process - - The \QWE Process is a separate executable that is used to render web pages and - execute JavaScript. This mitigates security issues and isolates crashes caused by specific - content. - - \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 can have a - QWebEngineHistory that provides access to the page's navigation history and several QAction - objects that apply actions on the web page. In addition, a QWebEnginePage has the ability to - run JavaScript code in the context of the page's main frame and to enable customization of - handlers for specific events like showing custom authentication dialogs. - - Each QWebEnginePage belongs to a QWebEngineProfile that can have a QWebEngineSettings - for specifying page settings, a QWebEngineScriptCollection for running scripts on the page, and - a QWebEngineCookieStore for accessing the HTTP cookies of Chromium. A QWebEnginePage can also - directly point to a script collection. - - For a widget based application, the web engine is automatically initialized, unless it is - placed in a plugin. In that case, it must be initialized in the application main source file - by using \l QtWebEngine::initialize, as illustrated by the following code snippet: - - \code - int main(int argc, char **argv) - { - QApplication app(argc, argv); - - QtWebEngine::initialize(); - - QMainWindow window; - window.show(); - - return app.exec(); - } - \endcode - - \section1 Embedding Web Content into Qt Quick Applications - - The WebEngineView QML type allows Qt Quick 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 Qt Quick application. - - To make sure that OpenGL context can be shared between the GUI and render processes, the web - engine must be initialized by using \l QtWebEngine::initialize in the application main source - file, as illustrated by the following code snippet: - - \code - int main(int argc, char *argv[]) - { - QGuiApplication app(argc, argv); - - QtWebEngine::initialize(); - - QQmlApplicationEngine engine; - engine.load(QUrl("qrc:/main.qml")); - - return app.exec(); - } - \endcode - - 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 using the \l{WebEngineView::}{url} - property: - - \quotefromfile webengine/minimal/main.qml - \skipto import - \printuntil /^\}/ - - \section1 Script Injection - - \QWE does not allow direct access to the document object model (DOM) of a page. - However, the DOM can be inspected and adapted by injecting scripts. - - The DOM of a page is constructed when the document is ready, typically - when the page is completely loaded. Therefore, executing scripts as soon as a document is - created is not suitable for DOM operations, where one has to wait until the DOM is ready. - - In addition, an injected script shares the same \e world as the other scripts executed on the - page, which might lead to conflicts. To avoid this, the QWebEngineScript class and the - WebEngineScript QML type provide implementations of the Chromium API for - \e{Content Script Extensions}. They specify the - script to run, the injection point, and the world where the script is run. This enables - accessing the DOM to manipulate it within a world. - - Since Qt 5.8, \QWE supports augmenting a script by using the - following \l{Metadata Block}{Greasemonkey-like attributes}: - - \list - \li \c {@exclude <regexp>} - \li \c {@include <regexp>} - \li \c {@match <regexp>} - \li \c {@name <free text>} - \li \c {@run-at [document-start|document-end|document-idle]} - \endlist - - The attributes determine if and when a \l {User Scripts}{user script} is - run. They must be placed immediately in the beginning of the script, inside - a \c ==UserScript== comment: - - \code - // ==UserScript== - // @include http://*.qt.io/* - // @exclude http://wiki.qt.io/* - // ==/UserScript== - - window.alert("Page is from qt.io, but not wiki.qt.io"); - \endcode - - If your WebEngine application is built using the Qt Quick Compiler, and the application ships - JavaScript files inside .qrc resources, consider reading the section - \l{JavaScript Files in Qt Resource Files}. - - \section1 Managing Certificates - - \QWE uses its own network stack, and therefore QSslConfiguration is not used to - open SSL connections. Instead, \QWE uses the root CA certificates from the operating - system to validate the peer's certificate. - - The \l{WebEngineCertificateError::error} and \l{QWebEngineCertificateError::Error} enumerations - provide information about the types of certificate errors that might occur. The errors can be - handled by using the WebEngineView::certificateError QML method or by reimplementing the - QWebEnginePage::certificateError function. - - \section1 Proxy Support - - \QWE uses the proxy settings from \l{Qt Network}, and forwards them to Chromium's - networking stack. If QNetworkProxy::applicationProxy is set, it will also be used for \QWE. - If QNetworkProxyFactory::usesSystemConfiguration() is enabled, the proxy settings - are automatically retrieved from the system. Settings from an installed QNetworkProxyFactory - will be ignored, though. - - In case QNetworkProxy::user() and QNetworkProxy::password() are set, these credentials - will be automatically used for proxy authentication. It is up to the user to provide valid - credentials, since there is no error handling callback. - - If no credentials are set with QNetworkProxy, but the proxy requires authentication, - QWebEnginePage::proxyAuthenticationRequired is emitted. - For Qt Quick, a dialog is shown. - - Not all properties of QNetworkProxy are supported by \QWE. That is, - QNetworkProxy::type(), QNetworkProxy::hostName() and QNetworkProxy::port() are taken into - account. All other proxy settings such as QNetworkProxy::rawHeader() are ignored. - - \section1 High DPI Support - - To support High DPI devices, it is recommended that the application attribute - Qt::AA_EnableHighDpiScaling is set to enable automatic scaling based on the - pixel density of the monitor. In \QWE applications, the scaling - affects the default zooming factor and scrollbar size. - - For example: - - \code - int main(int argc, char *argv[]) - { - QCoreApplication::setAttribute(Qt::AA_EnableHighDpiScaling); - QApplication app(argc, argv); - // ... - } - \endcode - - \QWE bundles images for normal and high-dpi resolutions into - \e qtwebengine_resources_100p.pak and \e qtwebengine_resources_200p.pak - files. Depending on the target resolutions, one or both of these files need - to be deployed. - - For more information, see \l{High DPI Displays}. - - \section1 Using WebEngine Core - - \QWE Core provides an API shared by \QWE and \QWE Widgets for handling - URL requests issued for the networking stack of Chromium and for accessing its HTTP cookies. - - Implementing the QWebEngineUrlRequestInterceptor interface and installing the interceptor on a - profile enables intercepting, blocking, and modifying URL requests (QWebEngineUrlRequestInfo) - before they reach the networking stack of Chromium. - - A QWebEngineUrlSchemeHandler can be registered for a profile to add support for custom URL - schemes. Requests for the scheme are then issued to QWebEngineUrlSchemeHandler::requestStarted() - as QWebEngineUrlRequestJob objects. - - The QWebEngineCookieStore class provides functions for accessing HTTP cookies of Chromium. - The functions can be used to synchronize cookies with QNetworkAccessManager, as well as to set, - delete, and intercept cookies during navigation. - - \section1 Platform Notes - - \QWE currently supports only Windows, Linux, and \macos. Due to Chromium build - requirements it also often requires a newer compiler than the rest of Qt. See - \l{Qt WebEngine Platform Notes} for further details. - - \section1 Related Modules - - \QWE supersedes the \l{http://doc.qt.io/archives/qt-5.3/qtwebkit-index.html}{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 \QWE widgets, see \l{Porting from Qt WebKit to Qt WebEngine}. - - The \l{Qt WebView} module allows to use a native web browser on platforms where one is - available. - - The \l{Qt WebChannel} module can be used to create a bi-directional communication channel - between QObject objects on the C++ side and JavaScript on the QML side. - -*/ |