qt-everywhere-src-5.15.1/qtwebengine/examples/webengine/quicknanobrowser/doc/src/quicknanobrowser.qdoc

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/*!
    \example webengine/quicknanobrowser
    \title WebEngine Quick Nano Browser
    \ingroup webengine-examples
    \brief A web browser implemented using the WebEngineView QML type.

    \image quicknanobrowser-demo.jpg

    \e {Quick Nano Browser} demonstrates how to use the \l{Qt WebEngine QML Types}
    {Qt WebEngine QML types} to develop a small web browser application that consists of a browser
    window with a title bar, toolbar, tab view, and status bar. The web content is loaded in a web
    engine view within the tab view. If certificate errors occur, users are prompted for action in a
    message dialog. The status bar pops up to display the URL of a hovered link.

    A web page can issue a request for being displayed in fullscreen mode. Users can allow full
    screen mode by using a toolbar button. They can leave fullscreen mode by using a keyboard
    shortcut. Additional toolbar buttons enable moving backwards and forwards in the browser
    history, reloading tab content, and opening a settings menu for enabling the following features:
    JavaScript, plugins, fullscreen mode, off the record, HTTP disk cache, autoloading images, and
    ignoring certificate errors.

    \include examples-run.qdocinc

    \section1 Creating the Main Browser Window

    When the browser main window is loaded, it creates an empty tab using the default profile. Each
    tab is a web engine view that fills the main window.

    We create the main window in the \e BrowserWindow.qml file using the ApplicationWindow type:

    \quotefromfile webengine/quicknanobrowser/BrowserWindow.qml
    \skipto ApplicationWindow
    \printuntil currentWebView
    \dots
    \skipto width
    \printuntil title

    We use the TabView Qt Quick control to create an empty tab view that fills the main window. We
    set the tab active first, to make sure that the tab item is immediately instantiated:

    \skipto TabView
    \printuntil Component.onCompleted

    The tab contains a web engine view that loads web content:

    \printuntil focus

    We use the \l Action type to create new tabs:

    \quotefromfile webengine/quicknanobrowser/BrowserWindow.qml
    \skipto reload
    \skipto Action
    \printuntil }

    We use the \l TextField Qt Quick Control within a \l ToolBar to create an address bar that
    shows the current URL and where users can enter another URL:

    \skipto toolBar
    \printuntil anchors.fill
    \dots
    \skipto TextField
    \printuntil addressBar
    \dots
    \skipto focus
    \printuntil /^\ {16}\}/

    \section1 Handling Certificate Errors

    If the certificate of the site being loaded triggers a certificate error, we call the
    \l{WebEngineCertificateError::}{defer()} QML method to pause the URL request and wait for user
    input:

    \quotefromfile webengine/quicknanobrowser/BrowserWindow.qml
    \skipto onCertificateError
    \printuntil }

    We use the MessageDialog type to prompt users to continue or cancel the loading of the web page.
    If users select \uicontrol Yes, we call the
    \l{WebEngineCertificateError::}{ignoreCertificateError()} method to ignore the error and
    continue loading content from the URL. If users select \uicontrol No, we call the
    \l{WebEngineCertificateError::}{rejectCertificate()} method to reject the request and stop
    loading content from the URL:

    \skipto MessageDialog
    \printuntil /^\ {4}\}/

    \section1 Entering and Leaving Fullscreen Mode

    We create a menu item for allowing fullscreen mode in a settings menu that we place on the tool
    bar. Also, we create an action for leaving fullscreen mode by using a keyboard shortcut.
    We call the \l{FullScreenRequest::}{accept()} method to accept the fullscreen request.
    The methdod sets the \l{WebEngineView::}{isFullScreen} property to be equal to the
    \l{FullScreenRequest::}{toggleOn} property.

    \quotefromfile webengine/quicknanobrowser/BrowserWindow.qml
    \skipto onFullScreenRequested
    \printuntil /^\ {16}\}/

    When entering fullscreen mode, we display a notification using the FullScreenNotification custom
    type that we create in \e FullScreenNotification.qml.

    We use the \l Action type in the settings menu to create a shortcut for leaving fullscreen mode
    by pressing the escape key:

    \quotefromfile webengine/quicknanobrowser/BrowserWindow.qml
    \skipto Settings
    \printuntil appSettings
    \skipto fullScreenSupportEnabled
    \printuntil Action
    \skipto Escape
    \printuntil /^\ {4}\}/

    \section1 Files and Attributions

    The example uses icons from the Tango Icon Library:

    \table
    \row
        \li \l{quicknanobrowser-tango}{Tango Icon Library}
        \li Public Domain
    \endtable
*/