Accessibility/Accessibility-dev

    From The Document Foundation Wiki

    LibreOffice has support for various Accessibility aspects: keyboard navigation, scheming, assistive technology (AT) support, and much more.

    LibreOffice is designed with great attention to accessibility, to make the suite convenient and comfortable to use, and to cater to users with special needs. If you find shortcomings or gaps in the features or the information provided, please consider helping to improve it, by telling us via our mailing list or by considering getting involved as a contributor to the project.

    Keyboard Navigation

    Full Keyboard Navigation and Control

    Full keyboard navigation gives the users the ability to perform all input via a keyboard, without using a mouse or other pointing device.

    The features that most notably enhance accessibility include:

    • Comprehensive definitions of keyboard shortcuts in the different applications;
    • Full keyboard access to toolbars;
    • Keyboard-enabled switching between document windows, menus, toolbars, modeless dialogs and floating windows;
    • Enhanced keyboard navigation in text documents and online help to navigate and activate hyperlinks;
    • Menu and toolbar items for accessing functions which where only accessible via mouse device;
    • Disabled menu items are displayed by default;
    • You can access help tips via keyboard;
    • You can set the duration for the display of help tips;
    • Keyboard access for Drawing Objects:
      • Drawing objects can be inserted via toolbar with default position and size;
      • Each handle of a drawing object can be selected and controlled via keyboard separately, so even polygon manipulation is possible;
    • Particular attention has been given to accessibility in dialog boxes, including:
      • the toolbar customization dialog;
      • extensive CSV import control for spreadsheets.

    Colors and Fonts

    Use of System Color Schemes, High Contrast

    LibreOffice adapts to the color schemes and contrast display settings of the operating system.

    In addition, LibreOffice offers additional settings for colors which are not specified in any system color schemes, as well as the possibility to overwrite colors from the current color scheme. You can also create and store your own color schemes in LibreOffice.

    The help system respects the colors from the current color scheme, but also provides different predefined styles. Users can customize the formatting of the help content via the XSL transformation file, as well as via the custom style sheet file located in the help directory.

    Automatic Text Color

    All LibreOffice applications support automatic text color for documents and use this by default, so the text is always distinguishable from the background color.

    The text will be displayed in the system text color. If this leads to dark text on a dark background, or bright text on a bright background, the text will switch to black or white (according to whichever provides better contrast).

    For reading old or imported documents which use hard-formatted text colors, you can use the option "Use automatic font color for screen display". All text content as well as table borders and some other elements will be displayed in the automatic font color.

    Icons and Bitmaps

    LibreOffice has icon sets for small and large toolbar icons in normal and in high contrast mode, so the icons are more easily identifiable in the different modes.

    All UI elements displaying a graphic offer an alternative graphic for high contrast mode.

    LibreOffice automatically chooses the set of icons and graphics appropriate for the current system settings.

    High Contrast Mode for Impress and Draw

    Impress and Draw offer a high-contrast mode, in which objects are displayed without fill colors or text colors.

    This mode will automatically be used when high contrast is chosen in the system settings. You can turn off this automatic detection in the LibreOffice options under �Accessibility �.

    System Font

    LibreOffice can use the operating system font for the user interface, so that LibreOffice appears in the same font as your other applications and can be manipulated via the system settings.

    There is special handling to ensure that dialogs do not become larger than the screen when schemes with large fonts are chosen.

    Other Legibility Features

    • Highlighted toolbar and menu items are easily perceptible;
    • There is distinct highlighting of current column and row in spreadsheets;
    • You can turn on/off animations for graphics and text.

    Assistive Technology

    API for Supporting Assistive Technologies

    Assistive Technology (AT) tools such as screen readers and magnifiers, as well as other tools, connect to LibreOffice using the native accessibility APIs of the corresponding platform (Microsoft Active Accessibility API (MSAA)/IAccessible2 on Windows, AT-SPI2 on GNU/Linux, NSAccessibility on macOS).

    LibreOffice UI elements and documents expose all the information about themselves and their contents via those accessibility APIs.

    An enormous effort has been made to have UI elements and document contents fully support the accessibility interfaces; for example: providing text with attributes and character bounds information, and sending all the necessary notifications and providing names and descriptions of controls.

    Some AT tools send key events to the applications, or simply control the mouse, so it makes no difference for the application if the input comes from a user or from an AT tool.

    This way, a lot of AT tools such as simple on-screen keyboards, head mice, eye tracking devices and single switches can be used with LibreOffice.

    Support for Comfortable Reading of Read-Only Documents

    Screen reader users sometimes have difficulty reading read-only documents because they cannot navigate with the cursor through the document.

    For this, there is the feature "Use text selection cursor in read-only text documents".

    Other AT features

    • Floating windows, dialogs and menus are system windows;
    • Every individual drawing object can have a name;
    • All sample documents and templates are enhanced to provide names and descriptions for drawing objects.

    Documentation

    Accessible Documentation

    All user documentation is provided in ODT and PDF formats so users can use screen readers and magnifiers to read the documentation. For more information about user documentation, please visit the Documentation site, or the Documentation page on our wiki.

    All keyboard shortcuts are documented in the online help.

    Accessible Online Help

    The online help provides information on how to use all the accessibility features in LibreOffice.

    The online help is accessible itself. Users can access it using screen readers, magnifiers and on-screen keyboards.

    More Accessibility Features

    Other features helpful for accessibility are also available:

    • Zoom in or zoom out in a document;
    • Position mouse to default button or center in dialogs;
    • Configuration:
      • Assign a shortcut key to a command;
      • Show all commands on menus;
      • Change the size of toolbar buttons;
      • Customize menus and toolbars;
      • Display or hide a toolbar;
      • Create a custom toolbar;
    • Task automation:
      • Correct misspelled words as you type;
      • Quickly set AutoCorrect and Paste options;
      • Add AutoCorrect entries for misspellings and typing errors;
      • Use AutoComplete;
      • Automatically make AutoText entries for frequently-used text.

    Java Accessibility Bridge

    Assistive Technology support on Windows is no longer dependent on the Java Accessibility Bridge to a Java runtime as the project has implemented an IAccessible2 (v1.3) based native bridge.

    Mailing List

    There is a mailing list ( accessibility@global.libreoffice.org) which can be used for user questions and comments, as well as for developer-related subjects.

    • Subscribe by sending a blank email to accessibility+subscribe@global.libreoffice.org.
    • or visit the archives

    LibreOffice AT support

    LibreOffice exposes its information to AT via the IAccessible2 API on Windows, via GNOME Accessibility API (ATK) on Linux with GNOME, and via NSAccessibility on macOS. This way LibreOffice should be accessible with AT supporting MSAA/IAccessible, ATK, or NSAccessibility.

    Windows

    When LibreOffice is launched and an AT is detected in use, accessible events will be detected and rendered as MSAA/IAccessible events without further action by the user. Additional adjustments to AT behavior can be made from the Tools ▸ Options ▸ LibreOffice ▸ Accessibility panel (and a few specialised options in the Tools ▸ Options ▸ LibreOffice ▸ Advanced panel's Expert Configuration dialog).

    GNOME

    Everything you need is included in current versions of GNOME.

    Activate the GNOME accessibility menu: in Settings ▸ Accessibility, turn on “Always Show Accessibility Menu”. More information can be found on the GNOME Help website.

    Accessibility/TextAttributes lists the mapping between LibreOffice text properties and ATK text attributes.

    macOS

    LibreOffice interacts well in general with the VoiceOver screen reader that is built into macOS. Enable the screen reader using ⌘ Command + F5 and set the options using control + ⌥ Option + F8. LibreOffice accepts the VoiceOver Navigation well and for the most part the options are available to the screen reader. Some options can't be accessed with the screen reader navigation.

    AT That Works

    • Windows, Screen Reader
      • ZoomText 7.11, 8.12, 9.x
      • JAWS 6.2, 7.x
      • NVDA (open source!)
    • Windows, Screen Magnifier
      • ZoomText 7.11, 8.12, 9.x
    • Windows, On Screen keyboard
      • Probably all, because they just send Windows messages
    • GNOME, Screen Reader
      • Orca
    • GNOME, Screen Magnifier
      • Universal Access ▸ Zoom
    • GNOME, On Screen keyboard
      • Universal Access ▸ Screen Keyboard
    • macOS
      • VoiceOver

    Orca

    In order to get LibreOffice speaking through the graphical screen reader Orca, you don't necessarily need to start a gnome-session in GNU/Linux. Setting and exporting the following variables in the shell, will tell the soffice command to use the atk-spi bridge of GTK.

    export SAL_USE_VCLPLUGIN=gtk3 GTK_MODULES="gail:atk-bridge"
    orca & # if not already running
    soffice file.odt

    With Orca running, all of LibreOffice's menu functions are accessible with speech and braille using the left Alt key or the right ≣ Menu key on your keyboard, in combination with navigation functions that Orca provides with its hotkeys (usually Scroll Lock plus one or more other keys).

    AT Support While Giving a Presentation

    While the normal (edit) mode for presentations works well with AT, the slide show itself doesn’t expose much information. The reason is the the slide show only has elements optimized for the slide show, and doesn’t know the real objects in the presentation document. Even knowing the real objects, it’s unclear how to best expose the content, given that you won’t see all content at once, but the many transition effects result in many changes to what you see on the screen.

    For making slide shows accessible, people should use the Presenter Console. (Please note the extension might not accessible - an update was due to be available around about the time of the release of OpenOffice.org 3.2.

    See also Presenter Console description on the OOo wiki for a description of the extension.

    In the presenter console, the critical information is exposed to AT: Current slide and its notes.

    We believe that the presentation slides itself are not a good source for gathering the critical information you need while giving a life presentation, and that people would put information they need in the notes.

    See Presenter Console Keyboard Shortcuts on the OOo wiki for a list of the support keyboard shortcuts.

    LibreOffice DAISY support

    An Extension for exporting ODT to DAISY / DTBOOK is available here:

    odt2dtbook LibreOffice Extension

    NVDA Support

    NV Access provides the free and opensource NVDA Assistive Technology screen reader for Windows os users from their home page at

    NVDA documentation and 3rd party service agencies providing training and support are available via the projects github hosted development. There are links from there to post bugs-reports, request features or help out with development

    The NVDA Community mail lists are via Groups.io and reachable at

    Development

    An accessibility for developers page records ongoing work.