Qt WebEngine 特徵

Qt WebEngine 支持下列特徵:

音頻和視頻編解碼器

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:

-proprietary-codecs
					

警告: 當分發專有編解碼器庫時,它們必須獲得許可。

FFmpeg 是錄製、轉換及流化音頻 視頻的跨平颱解決方案。可以將其配置為與多個編解碼器一起使用,但帶編解碼器庫分發時會引發許可問題。對於某些編解碼器,開源實現,譬如 OpenH264 ,是可用的。

Chromium DevTools

Chromium DevTools 提供審查 調試任何 Web 內容的布局和性能問題的能力。

可以測試此特徵通過啓動 Qt WebEngine 應用程序采用命令行選項 --remote-debugging-port=[your-port] 或通過設置環境變量 QTWEBENGINE_REMOTE_DEBUGGING ,然後使用基於 Chromium 的瀏覽器 (譬如 Demo Browser or 納米瀏覽器 ) 去連接到 http://localhost:[your-port] .

更多信息,見 Qt WebEngine 調試和剖分析 .

拖放

Qt WebEngine 支持 HTML5 拖放。

可以通過打開 HTML5 拖放演示來測試此特徵,譬如 HTML5 演示 - 拖放 , HTML5 演示 - 簡單拖放 ,或 HTML5 演示 - 拖放,自動上傳 , in Demo Browser or 納米瀏覽器 .

把文件拖拽到瀏覽器中實際上不屬於 HTML5,但它是受支持的。可以測試它通過打開 HTML5 演示 - 文件 API .

該特徵支持在 Qt 5.7.0 添加。

Fullscreen

Qt WebEngine supports viewing web content in fullscreen mode. For more information, see WebEngineSettings.fullscreenSupportEnabled , WebEngineView.fullScreenRequested , QWebEngineSettings::FullScreenSupportEnabled ,和 QWebEnginePage::fullScreenRequested .

This feature can be tested by playing a video from YouTube in Demo Browser or 納米瀏覽器 , and clicking the full screen icon to go into fullscreen mode.

該特徵支持在 Qt 5.6.0 添加。

HTML5 DRM

Qt WebEngine 支持查看 DRM (數字版權管理) 保護視頻若 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 音頻和視頻編解碼器 .

This feature can be tested by playing a video in Demo Browser or 納米瀏覽器 from castLabs , Swank Motion Pictures, Inc. ,或 Shaka Player .

該特徵支持在 Qt 5.7.0 添加。

HTML5 地理位置

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

This feature can be tested if Qt Location has been built before Qt WebEngine. The http://html5demos.com/geo page can be opened in the 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 Qt Positioning .

該特徵支持在 Qt 5.5.0 添加。

HTTP/2 協議

Qt WebEngine supports the Chromium implementation of the HTTP/2 協議。

This feature can be tested by opening an HTTP/2 demo, such as the Akamai HTTP/2 Demo , in 簡單瀏覽器 or 納米瀏覽器 .

本機對話框

A web page might request dialogs for the following functions:

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

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 eglfs 平颱。

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

Qt WebEngine Widgets dialogs can be customized by reimplementing the QWebEnginePage::chooseFiles (), QWebEnginePage::javaScriptAlert (), QWebEnginePage::javaScriptConfirm (),和 QWebEnginePage::javaScriptPrompt () 函數。

Since Qt 5.8, Qt Quick dialogs can be customized by connecting to the WebEngineView::authenticationDialogRequested (), WebEngineView::javaScriptDialogRequested (), WebEngineView::colorDialogRequested (), WebEngineView::fileDialogRequested (),和 WebEngineView::formValidationMessageRequested () signals. For an example, see WebEngine Qt Quick 自定義對話框範例 .

Pepper 插件 API

Qt WebEngine supports loading Pepper Plugin API (PPAPI) plugins if WebEngineSettings::pluginsEnabled or QWebEngineSettings::PluginsEnabled 有設置。

Except for the Adobe Flash Player plugin, the plugins must be loaded manually using the Chromium command line syntax with the --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:

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

例如:

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

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

該特徵支持在 Qt 5.6.0 添加。

Pepper Flash Player 插件支持

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

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

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

--ppapi-flash-path=./libpepflashplayer.so
					

By default, the Flash version is set to 11.2.999.999 。可以使用 ppapi-flash-version= argument to set another Flash version in the format major.minor.build.revision :

--ppapi-flash-version=16.0.0.235
					

This feature can be tested in Demo Browser or 納米瀏覽器 if the Adobe Flash PPAPI plugin is installed and plugins are enabled in the browser. To test the feature, the https://helpx.adobe.com/flash-player.html page can be opened in the browser.

Qt WebEngine 支持把網頁打印成 PDF 文件。更多信息,見 QWebEnginePage::printToPdf () 和 WebEngineView.printToPdf .

This feature can be tested in Demo Browser by selecting File > 打印到 PDF .

該特徵支持在 Qt 5.7.0 添加。

拼寫檢查器

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 Hunspell project , but they have to be compiled into a special binary format. A Hunspell dictionary consists of two files:

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

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

可以測試此特徵通過構建和運行 拼寫檢查器範例 .

該特徵支持在 Qt 5.8.0 添加。

觸摸

Qt WebEngine 支持導航和交互網頁的觸摸設備。

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

  • Passing the flag --touch-events=disabled on the command line will disable touch event support in JavaScript API (meaning ontouchstart and related handlers will not be present in the document.window object). Touch events will still be delivered to web pages.
  • Installing an event filter object using QObject::installEventFilter on the WebEngine view focus proxy object, and filtering out all touch events.

查看源

Qt WebEngine 支持查看網頁的 HTML 源。

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

This feature can be tested by opening a web page in 簡單瀏覽器 or 納米瀏覽器 , and then selecting Page Source in the context menu. The Page Source context menu entry opens the source view in a new tab.

For opening the source view in the current tab, URLs with 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:

view-source:https://www.qt.io/
					

Auto-completion of incomplete URLs with 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:

view-source:qt.io
					

該特徵支持在 Qt 5.8.0 添加。

WebRTC

WebRTC 憑藉簡單 API 為瀏覽器提供 RTC (實時通信) 能力。更多信息,見 WebEngineView.Feature and QWebEnginePage::Feature .

This feature can be tested by setting up a webcam or microphone and then opening https://test.webrtc.org/ in 簡單瀏覽器 or 納米瀏覽器 .