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/*!
    \page qtwebengine-features.html
    \title Qt WebEngine Features

    \brief Summarizes Qt WebEngine features.

    Qt WebEngine supports the following features:

    \list
        \li \l{Audio and Video Codecs}
        \li \l{Chromium DevTools}
        \li \l{Drag and Drop}
        \li \l{Fullscreen}
        \li \l{HTML5 DRM}
        \li \l{HTML5 Geolocation}
        \li \l{HTTP/2 Protocol}
        \li \l{Native Dialogs}
        \li \l{Pepper Plugin API}
        \li \l{Print to PDF}
        \li \l{Spellchecker}
        \li \l{Touch}
        \li \l{View Source}
        \li \l{WebRTC}
    \endlist

    \section1 Audio and Video Codecs

    Qt WebEngine supports the MPEG-4 Part 14 (MP4) file format only if the
    required proprietary audio and video codecs, such as H.264 and MPEG layer-3
    (MP3), have been enabled. Proprietary codecs can be enabled by passing the
    following option when configuring Qt:

    \code
    -proprietary-codecs
    \endcode

    \warning When distributing proprietary codec libraries, you must acquire
    licenses for them.

    \l FFmpeg is a cross-platform solution to record, convert, and stream audio
    and video. It can be configured for use with several codecs, which rises
    licensing issues during distribution with the codec libraries. For some
    codecs, open source implementations, such as \l{OpenH264 Project Homepage}
    {OpenH264}, are available.

    \section1 Chromium DevTools

    The Chromium DevTools provide the ability to inspect and debug layout and
    performance issues of any web content.

    This feature can be tested by launching a Qt WebEngine application with the
    command line option \c {--remote-debugging-port=[your-port]} or by setting
    the environment variable \c QTWEBENGINE_REMOTE_DEBUGGING, and then using a
    Chromium based browser (such as \l{WebEngine Demo Browser Example}
    {Demo Browser} or \l{WebEngine Quick Nano Browser}{Nano Browser}) to connect
    to \c {http://localhost:[your-port]}.

    For more information, see \l {Qt WebEngine Debugging and Profiling}.

    \section1 Drag and Drop

    Qt WebEngine supports HTML5 drag and drop.

    This feature can be tested by opening an HTML5 drag and drop demo, such as
    \l{HTML5 Demos - Drag and Drop}, \l{HTML5 Demos - Simple Drag and Drop}, or
    \l{HTML5 Demos - Drag and Drop, Automatic Upload}, in \l{WebEngine Demo
    Browser Example}{Demo Browser} or \l{WebEngine Quick Nano Browser}
    {Nano Browser}.

    Dragging files into the browser is not actually part of HTML5, but it is
    supported. It can be tested by opening \l{HTML5 Demos - File API}.

    Support for this feature was added in Qt 5.7.0.

    \section1 Fullscreen

    Qt WebEngine supports viewing web content in fullscreen mode. For more
    information, see \l{WebEngineSettings::fullscreenSupportEnabled}
    {WebEngineSettings.fullscreenSupportEnabled},
    \l{WebEngineView::fullScreenRequested}{WebEngineView.fullScreenRequested},
    QWebEngineSettings::FullScreenSupportEnabled, and
    QWebEnginePage::fullScreenRequested.

    This feature can be tested by playing a video from YouTube in \l{WebEngine
    Demo Browser Example}{Demo Browser} or \l{WebEngine Quick Nano Browser}
    {Nano Browser}, and clicking the full screen icon to go into fullscreen
    mode.

    Support for this feature was added in Qt 5.6.0.

    \section1 HTML5 DRM

    Qt WebEngine supports viewing DRM protected videos if the \l{Widevine DRM}
    plugin has been installed.

    The video format most commonly used by DRM services, H.264, requires
    proprietary audio and video codecs. For more information about enabling the
    codecs, see \l{Audio and Video Codecs}.

    This feature can be tested by playing a video in \l{WebEngine Demo Browser
    Example}{Demo Browser} or \l{WebEngine Quick Nano Browser}{Nano Browser}
    from \l{castLabs}, \l{Swank Motion Pictures, Inc.}, or \l{Shaka Player}.

    Support for this feature was added in Qt 5.7.0.

    \section1 HTML5 Geolocation

    Qt WebEngine supports JavaScript Geolocation API with \l {Qt Location} as a
    backend. The application has to explicitly allow the feature by using
    QWebEnginePage::Geolocation or \l{WebEngineView::Feature}
    {WebEngineView.Feature}.

    This feature can be tested if Qt Location has been built before Qt WebEngine.
    The \c http://html5demos.com/geo page can be opened in the \l{WebEngine Demo
    Browser Example}{Demo Browser} and allowed to find the current position of
    the user. Note that on Windows an external GPS receiver must be connected to
    the application. For more information, see \l{Qt Positioning}.

    Support for this feature was added in Qt 5.5.0.

    \section1 HTTP/2 Protocol

    Qt WebEngine supports the Chromium implementation of the \l{HTTP/2}
    protocol.

    This feature can be tested by opening an HTTP/2 demo, such as the
    \l{Akamai HTTP/2 Demo}, in \l{WebEngine Widgets Simple Browser Example}
    {Simple Browser} or \l{WebEngine Quick Nano Browser}{Nano Browser}.

    \section1 Native Dialogs

    A web page might request dialogs for the following functions:

    \list
        \li Entering user credentials for HTTP and proxy authentication
        \li Displaying JavaScript alerts, confirmation dialogs, and prompts
        \li Picking colors
        \li Selecting files
        \li Displaying form validation messages
    \endlist

    Qt WebEngine provides standard dialogs for these functions. In widget-based
    applications, the standard dialogs are based on QDialog, whereas in Qt Quick
    applications, they can be based either on Qt Quick Controls 1 or Qt Quick
    Controls 2 (since Qt 5.8). The latter are used only on \c eglfs platforms.

    To explicitly force either dialogs based on Qt Quick Controls 1 or Qt Quick
    Controls 2, set the \c QTWEBENGINE_DIALOG_SET environment variable to either
    \c{QtQuickControls1} or \c{QtQuickControls2}.

    Qt WebEngine Widgets dialogs can be customized by reimplementing the
    QWebEnginePage::chooseFiles(), QWebEnginePage::javaScriptAlert(),
    QWebEnginePage::javaScriptConfirm(), and QWebEnginePage::javaScriptPrompt()
    functions.

    Since Qt 5.8, Qt Quick dialogs can be customized by connecting to the
    WebEngineView::authenticationDialogRequested(),
    WebEngineView::javaScriptDialogRequested(),
    WebEngineView::colorDialogRequested(),
    WebEngineView::fileDialogRequested(), and
    WebEngineView::formValidationMessageRequested() signals. For an example,
    see \l{WebEngine Qt Quick Custom Dialogs Example}.

    \section1 Pepper Plugin API

    Qt WebEngine supports loading Pepper Plugin API (PPAPI) plugins if
    WebEngineSettings::pluginsEnabled or QWebEngineSettings::PluginsEnabled
    is set.

    Except for the Adobe Flash Player plugin, the plugins must be loaded
    manually using the Chromium command line syntax with the
    \c --register-pepper-plugins argument. The argument value is a list of
    entries, separated by commas, that contain the file path and one or several
    MIME types, separated by semicolons:

    \code
    <file-path-plugin1>;<mime-type-plugin1>,<file-path-plugin2>;<mime-type1-plugin2>;<mime-type2-plugin2>
    \endcode

    For example:

    \code
    --register-pepper-plugins="libppapi_example.so;application/x-ppapi-example"
    \endcode

    The MIME type is important because it determines which embeds the plugin is
    used for.

    Support for this feature was added in Qt 5.6.0.

    \section2 Pepper Flash Player Plugin Support

    The Pepper Flash player plugin can be loaded automatically if it is
    installed in one of the following locations, depending on the platform:

    \list
        \li Windows
            \code
            C:\Windows\SysWOW64\Macromed\Flash\pepflashplayer*.dll
            C:\Windows\System32\Macromed\Flash\pepflashplayer*.dll
            \endcode
        \li OS X
            \code
            /Library/Internet Plug-Ins/PepperFlashPlayer/PepperFlashPlayer.plugin
            \endcode
        \li Linux
            \code
            /usr/lib/pepperflashplugin-nonfree/libpepflashplayer.so
            /usr/lib/adobe-flashplugin/libpepflashplayer.so
            /usr/lib/PepperFlash/libpepflashplayer.so
            /usr/lib64/chromium/PepperFlash/libpepflashplayer.so
            \endcode
    \endlist

    You can also load the Pepper Flash player from a specific location by using
    command line arguments:

    \code
    --ppapi-flash-path=./libpepflashplayer.so
    \endcode

    By default, the Flash version is set to \c{11.2.999.999}. You can use the
    \c{ppapi-flash-version=} argument to set another Flash version in the
    format \c{major.minor.build.revision}:

    \code
    --ppapi-flash-version=16.0.0.235
    \endcode

    This feature can be tested in \l{WebEngine Demo Browser Example}{Demo Browser}
    or \l{WebEngine Quick Nano Browser}{Nano Browser} if the Adobe Flash PPAPI
    plugin is installed and plugins are enabled in the browser. To test the
    feature, the \c https://helpx.adobe.com/flash-player.html page can be opened
    in the browser.

    \section1 Print to PDF

    Qt WebEngine supports printing a web page to a PDF file. For more
    information, see QWebEnginePage::printToPdf() and
    \l{WebEngineView::printToPdf}{WebEngineView.printToPdf}.

    This feature can be tested in \l{WebEngine Demo Browser Example}
    {Demo Browser} by selecting \uicontrol File > \uicontrol {Print to PDF}.

    Support for this feature was added in Qt 5.7.0.

    \section1 Spellchecker

    Qt WebEngine supports integrating spellchecking support into HTML forms to
    enable users to submit spellchecked messages. When the user clicks on
    an underlined misspelled word, the default context menu displays up to four
    suggestions. Selecting one will replace the misspelled word.

    To be able to check the spelling, the spellchecker needs dictionaries. It
    supports dictionaries from the \l{Hunspell project}, but they have to be
    compiled into a special binary format. A Hunspell dictionary consists of two
    files:

    \list

        \li A \c .dic file that is a dictionary containing words for the
            language
        \li An \c .aff file that defines the meaning of special flags in the
            dictionary
    \endlist

    These two files can be converted into the \c bdic format by using the
    \c qwebengine_convert_dict tool that is shipped together with Qt.
    When the Qt WebEngine spellchecker initializes, it will try to load the
    \c bdict dictionaries and to check them for consistency. First, it searches
    \e qtwebengine_dictionaries directories relative to the executable,
    then it will look in \c QT_INSTALL_PREFIX/qtwebengine_dictionaries.

    Spellchecking is disabled by default and can be enabled per profile by
    using the QWebEngineProfile::setSpellCheckEnabled() method in widget-based
    applications and the \l {QQuickWebEngineProfile::spellCheckEnabled}
    {WebEngineProfile.spellCheckEnabled} property in Qt Quick applications.

    The current language used for spellchecking is defined per profile, and can
    be set using the QWebEngineProfile::setSpellCheckLanguages() method or the
    \l {QQuickWebEngineProfile::spellCheckLanguages}
    {WebEngineProfile.spellCheckLanguages} property.

    This feature can be tested by building and running the
    \l{WebEngine Widgets Spellchecker Example}{Spellchecker Example}.

    Support for this feature was added in Qt 5.8.0.

    \section1 Touch

    Qt WebEngine supports touch devices for navigating and interacting with web pages.

    Applications can prohibit the use of touch events in the following ways:

    \list
        \li Passing the flag \c --touch-events=disabled on the command line will disable touch event
        support in JavaScript API (meaning \c ontouchstart and related handlers will not be present
        in the \c document.window object). Touch events will still be delivered to web pages.

       \li Installing an event filter object using \l {QObject::installEventFilter} on the WebEngine
       view focus proxy object, and filtering out all touch events.

    \endlist

    \section1 View Source

    Qt WebEngine supports viewing the HTML source of a web page.

    This feature can be used from custom menus or assigned to custom events.
    For more information, see WebEngineView::WebAction, and QWebEnginePage::WebAction.

    This feature can be tested by opening a web page in \l{WebEngine Widgets
    Simple Browser Example}{Simple Browser} or \l{WebEngine Quick Nano Browser}
    {Nano Browser}, and then selecting \c{Page Source} in the context menu. The
    \c{Page Source} context menu entry opens the source view in a new tab.

    For opening the source view in the current tab, URLs with \l{view-source URI scheme}
    are also supported. For example, you can type the following URL to the URL bar
    to view the HTML source of the qt.io web page:
    \code
    view-source:https://www.qt.io/
    \endcode

    Auto-completion of incomplete URLs with \l{view-source URI scheme} makes the usage of
    this feature more comfortable. For example, the following incomplete URL also loads
    the source view of the qt.io web page:
    \code
    view-source:qt.io
    \endcode

    Support for this feature was added in Qt 5.8.0.

    \section1 WebRTC

    WebRTC provides browsers with Real-Time Communications (RTC) capabilities
    via simple APIs. For more information, see \l{WebEngineView::Feature}
    {WebEngineView.Feature} and QWebEnginePage::Feature.

    This feature can be tested by setting up a webcam or microphone and then
    opening \c https://test.webrtc.org/ in \l{WebEngine Widgets Simple Browser
    Example}{Simple Browser} or \l{WebEngine Quick Nano Browser}{Nano Browser}.
*/
