GNOME Accessibility Guide - Documentation Review



Greetings! I have been appointed for documentation rewrites and
additions and have checked in all GNOME Accessibility Guide (GAG)
DocBook xml files for community review. This set of changes mostly
include alterations for consistency, a few typo corrections,
occasional rewording and other minor adjustments. The bulk of the
GNOME Accessibility Guide remains intact as developed by Shaun
McCance.

Here is the repository address along with svn anonymous checkout syntax:

svn checkout http://svn.gnome.org/svn/gnome-user-docs/trunk/gnome2-accessibility-guide
MyDir

You can view the DocBook xml files directly, the attached "unchunked"
HTML, or via any DocBook build process (please refer to DocBook
documenttion for the last method as it pertains to your environment).

Thanks in advance for all suggestions, corrections, criticisms and concerns.
Title: GNOME Desktop Accessibility Guide

GNOME Desktop Accessibility Guide

Don Scorgie

GNOME Documentation Project

Brent Smith

GNOME Documentation Project

Sun Java Desktop System Documentation Team

Sun Microsystems, Inc.

The GNOME Accessibility Guide is for users, system administrators, and anyone else who is interested in how the GNOME Desktop supports people with disabilities. This guide also addresses the requirements of Section 508 of the U.S. Rehabilitation Act.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License (GFDL), Version 1.1 or any later version published by the Free Software Foundation with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. You can find a copy of the GFDL here or in the file COPYING-DOCS distributed with this manual.

This manual is part of a collection of GNOME manuals distributed under the GFDL. If you want to distribute this manual separately from the collection, you can do so by adding a copy of the license to the manual, as described in Section 6 of the license.

Many of the names used by companies to distinguish their products and services are claimed as trademarks. Where those names appear in any GNOME documentation, and the members of the GNOME Documentation Project are made aware of those trademarks, then the names are in capital letters or initial capital letters.

DOCUMENT AND MODIFIED VERSIONS OF THE DOCUMENT ARE PROVIDED UNDER THE TERMS OF THE GNU FREE DOCUMENTATION LICENSE WITH THE FURTHER UNDERSTANDING THAT:

  1. DOCUMENT IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES THAT THE DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT IS FREE OF DEFECTS MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY, ACCURACY, AND PERFORMANCE OF THE DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT IS WITH YOU. SHOULD ANY DOCUMENT OR MODIFIED VERSION PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT THE INITIAL WRITER, AUTHOR OR ANY CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL PART OF THIS LICENSE. NO USE OF ANY DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT IS AUTHORIZED HEREUNDER EXCEPT UNDER THIS DISCLAIMER; AND

  2. UNDER NO CIRCUMSTANCES AND UNDER NO LEGAL THEORY, WHETHER IN TORT (INCLUDING NEGLIGENCE), CONTRACT, OR OTHERWISE, SHALL THE AUTHOR, INITIAL WRITER, ANY CONTRIBUTOR, OR ANY DISTRIBUTOR OF THE DOCUMENT OR MODIFIED VERSION OF THE DOCUMENT, OR ANY SUPPLIER OF ANY OF SUCH PARTIES, BE LIABLE TO ANY PERSON FOR ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OF ANY CHARACTER INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF GOODWILL, WORK STOPPAGE, COMPUTER FAILURE OR MALFUNCTION, OR ANY AND ALL OTHER DAMAGES OR LOSSES ARISING OUT OF OR RELATING TO USE OF THE DOCUMENT AND MODIFIED VERSIONS OF THE DOCUMENT, EVEN IF SUCH PARTY SHALL HAVE BEEN INFORMED OF THE POSSIBILITY OF SUCH DAMAGES.

Feedback

To report a bug or make a suggestion regarding the GNOME Desktop or this manual, follow the directions in the GNOME Feedback Page .



Chapter 1. Introduction to Accessibility

This chapter introduces you to accessibility in the GNOME Desktop.

All software products should incorporate accessibility features to enable people with disabilities to use the software easily and efficiently. Recent legislation such as Section 508 of the U.S. Rehabilitation Act heightens awareness of the need to provide accessible software.

The GNOME Desktop is easy to use and incorporates many accessibility features. Every supported application and utility in the GNOME Desktop is designed with accessibility and usability in mind. Users with physical disabilities such as low vision or impaired motor skills can use all of the functionality of the GNOME Desktop thanks to the customization tools that are available. These customization tools enable you to fine-tune the appearance and behavior of the desktop.

The ability to easily customize the GNOME Desktop contributes greatly to the accessibility of the desktop. This guide describes the various options available to meet your particular needs.


Chapter 2. Enabling Accessibility Tools

You must enable the assistive technology services before you are able to use many of the accessibility tools available.

  1. Choose System->Preferences->Assistive Technologies.

  2. Select Enable assistive technologies and then press Close and Log Out.

  3. Log back in. The assistive technology services will be started automatically.

Once basic assistive technology support is enabled, it is possible to start accessibility services such as the screen reader, screen magnifier and on-screen keyboard.


Chapter 3. General Accessibility Tips

A number of technologies can be of assistance to people with different types of disabilities. These are covered in this section. In particular:

  • Keyboard Desktop Navigation - allows users to navigate the desktop without using a mouse or pointer device.

  • Accessible Login - users can configure the login screen to be more accessible.


3.1. Accessible Login

The GNOME Desktop includes an Accessible Login feature, enabling users to:

  • Log in to the desktop even if the user cannot easily use the screen, mouse, or keyboard in the usual way.

  • Launch assistive technologies at login time by associating a user action with an assistive technology application. The user can perform the user action from the standard keyboard, or from a keyboard, pointing device, or switch device that is attached to the USB or PS/2 mouse port. These user actions are called gestures.

  • Change the visual appearance of the login dialog before the user logs in; for example, using a high-contrast theme for better visibility.


3.1.1. Enabling Accessible Login

To configure GDM, perform the following steps:

  1. Log in as the root user.

  2. Open the file /etc/X11/gdm/gdm.conf

  3. Search the file for the following line:

    #AddGtkModules=false

    and replace the line with the following:

    AddGtkModules=true

    This step enables the GtkModules.

  4. Search the file for the following line:

    #GtkModulesList=gail:atk-bridge:dwellmouselistener:keymouselistener

    and delete the # from the start of the line so that the line reads:

    GtkModulesList=gail:atk-bridge:dwellmouselistener:keymouselistener

    Note

    The above lines must be displayed as single lines in the gdm.conf file without line breaks. The formatting of this guide may display the lines as being longer than two lines.

    This step loads all of the GtkModules to enable assistive technologies such as On-Screen Keyboard and Screen Reader and Magnifier . You can edit the line above further to load only the GtkModules that you require to support the user base. For example:

    • If you need to use the Screen Reader and Magnifier, include gail and atk-bridge.

    • If you need to use a pointing device without buttons or switches, include gail, atk-bridge and dwellmouselistener.

    • If you use pointing devices with switches, alternative physical keyboards, or switch and button devices, include keymouselistener.

    • On-Screen Keyboard can operate without gail and atk-bridge, but with a reduced feature set.

    For optimum accessibility, include gail and atk-bridge.

  5. Save the /etc/X11/gdm/gdm.conf file.

    Note

    If you make any changes to the /etc/X11/gdm/gdm.conf file after you enable GDM, you can execute the following command to restart GDM and activate the changes:

    gdm-restart

  6. Edit the file /etc/group and append the following to the audio line:

    ,gdm

    This step ensures that speech works with GDM.

  7. Restart your system.


3.1.2. Starting Assistive Technologies at Login

If you load the keymouselistener and dwellmouselistener GtkModules in the GDM configuration file, you can assign user actions to launch specific assistive technologies at login time. These user actions are called gestures. The gesture associations are contained in the following GDM configuration files:

  • /etc/X11/gdm/modules/AccessKeyMouseEvents

  • /etc/X11/gdm/modules/AccessDwellMouseEvents

Note

If you modify these files, you must restart your system before the changes take effect.

The following sections contain examples of the gestures that you can add to the GDM configuration files.

Note

The gestures must be contained in a single line in the AccessKeyMouseEvents file without line breaks. The formatting of this guide might display the examples in the following sections across multiple lines.


3.1.2.1. Starting the Screen Reader Using a Keyboard Shortcut

Edit the AccessKeyMouseEvents file to associate keyboard shortcuts with assistive technologies. For example, the following line enables you to press and hold Ctrl-S for one second to start Screen Reader and Magnifier in speech and Braille mode:

<Control>s 1 1000 10000 srcore --login --disable-magnifier --enable-speech --enable-braille


3.1.2.2. Starting Magnifier Using a Keyboard Shortcut

Edit the AccessKeyMouseEvents file to associate keyboard shortcuts with assistive technologies. For example, the following line enables you to press and hold Ctrl-M for one second to start Screen Reader and Magnifier in magnifier mode:

<Control>m 1 1000 10000 srcore --login --enable-magnifier --disable-speech


3.1.2.3. Starting On-Screen Keyboard Using a Switch or Button Gesture

Edit the AccessKeyMouseEvents file to associate switch, key, or button gestures with assistive technologies. Since the primary input device for many On-Screen Keyboard users is a switch or button, this is a good way to enable users to start On-Screen Keyboard at login time.

If there is a tendency for a user to start an application unintentionally, you can associate the gestures with multiple switch presses or minimum durations. For example, the following line starts On-Screen Keyboard in inverse scanning mode when the user presses the switch that is defined as Switch 2 three times within two seconds, for a minimum of 100 milliseconds for each press:

<Switch2>3 100 2000 gok --login --accessmethod=inversescanning --scan-action="" --select-action="" >

Users who use single switches may prefer to start On-Screen Keyboard in automatic scanning mode. The following line starts On-Screen Keyboard in automatic scanning mode when the user presses the switch on an alternative access device for more than four seconds:

<Switch>1 4000 5000 gok --login --accessmethod=automaticscanning --scan-action="" --select-action="" >

For information about the On-Screen Keyboard operating modes, see the online help for On-Screen Keyboard.


3.1.2.4. Starting On-Screen Keyboard Using a Motion-Only Gesture

You can define gestures that involve only the motion of a pointing device such as a mouse, or an alternative pointing device, such as a head pointer or trackball. The syntax of the gesture does not change depending on whether you are using a mouse or an alternative pointing device. Edit the AccessKeyMouseEvents file to associate motion gestures with assistive technologies.

If the dwellmouselistener GtkModule is loaded, alternative pointing devices are temporarily latched to the core pointer. This means that if the user moves the alternative pointing device, the on-screen pointer moves.

For example, the following line starts On-Screen Keyboard in dwell mode when the user moves the on-screen pointer from inside the login dialog through the top edge, back into the dialog through the top edge, out of the dialog through the left edge, back into the dialog through the left edge, and similarly through the bottom and right edges of the dialog in a cross pattern:

TTLLBBRR O 10000 gok --login --access-method=dwellselection --input-device=MOUSE[3]

Note that the --input-device parameter specified in the gesture must match the name of the extended user input device, such as a head pointer or trackball, as specified in /etc/X11/XF86Config.


3.1.3. Additional Requirements for Accessible Login

To enable the Accessible Login feature to use alternative pointing devices and switch devices such as sip-and-puff switches, wheelchair-mounted switches or trackballs, you might need to modify your X server system configuration to recognize these devices. You can use most devices that emulate mouse buttons with the Accessible Login feature and On-Screen Keyboard, including USB single switches and mouse-like pointing devices.

Note

You should not configure an alternative input device to control the primary on-screen pointer. This might result in undesirable behavior or cause situations from which the user of the alternate input device cannot recover without using the primary keyboard or mouse. To prevent this problem, remove any occurrences of the attributes SendCore or AlwaysCore from any of the InputDevice lines in the X Server configuration file.


3.2. Keyboard Desktop Navigation

This section describes how to navigate the GNOME Desktop from the keyboard only. Users who have difficulty using a mouse or other pointing device can navigate and use the desktop from the keyboard.


3.2.1. Introduction to Keyboard Navigation

This section describes the essential keyboard shortcuts to enable you to navigate the desktop from the keyboard.

You can customize some of the keyboard shortcuts that are described in this chapter. The text indicates the shortcuts that you can customize. See Section 3.2.10 for information about how to customize keyboard shortcuts.


3.2.1.1. Essential Keyboard Shortcuts

The following table lists the essential keyboard shortcuts that you can use to navigate the desktop. The keyboard shortcuts that you use to navigate specific elements and controls are described in the appropriate sections of this chapter.

Keys

Function

Tab

Give focus to the next element or control.

Shift-Tab

Reverse the navigation direction and give focus to the previous element or control. In general, the Shift key reverses the navigation direction.

Ctrl-Tab

Give focus to the next element or control if the Tab key has a specific purpose in a control. For example, if you press Tab in a text box, the system inserts a tab space.

To give focus to the previous element or control, press Shift-Ctrl-Tab.

arrow keys

Navigate within an element or control.

spacebar

Activate the element or control that has focus. For example, if the current control is a button, this action is the equivalent of clicking on the button with a mouse.

Esc

Close a window, menu, or drawer.

F7

Switch to caret navigation mode. Caret navigation mode enables you to use the keyboard to select text. For more information about caret navigation mode, see Section 3.2.8.


3.2.1.2. Global Keyboard Shortcuts

The following table lists the keyboard shortcuts that you can use from any part of the GNOME Desktop.

Keys

Function

Alt-F1

Open the Main Applications Menu.

You can customize this keyboard shortcut.

Alt-F2

Open the Run Application dialog.

You can customize this keyboard shortcut.

Print Screen

Start the screenshot application and take a screenshot of the entire screen.

You can customize this keyboard shortcut.

Alt- Print Screen

Start the screenshot application and take a screenshot of the window that currently has focus.

You can customize this keyboard shortcut.

F1

If the focused element is an application window or dialog, this keyboard shortcut opens the Help for the application.

Ctrl-F1

If the focused element is a panel or application window, this keyboard shortcut switches the display of tooltips for the window or panel objects on and off.

Shift-F10

Open a popup menu for the element that has focus (if a popup menu exists for that element).


3.2.2. Navigating the Desktop Background

The desktop background is the part of the GNOME Desktop where there are no interface items or applications, such as panels and windows. The following table lists the keyboard shortcuts that you can use to navigate the desktop background and the desktop background objects. A desktop background object is an icon on the desktop background that you can use to open files, folders, or applications.

Keys

Function

Ctrl-Alt -D

Temporarily hide all windows and give focus to the desktop background.

To restore the windows, press Ctrl-Alt-D again.

You can customize this keyboard shortcut.

Ctrl-Alt -Tab

Display a popup window with icons that represent the desktop background and the panels. Press and hold Ctrl-Alt and continue to press Tab to switch the focus between the desktop background and the panels.

You can customize this keyboard shortcut.

arrow keys

Give focus to a neighboring desktop background object (if the desktop has focus).

A sequence of characters that matches the first n characters of a desktop background object name.

If the desktop background has focus, give focus to the desktop background object whose name starts with the specified sequence of characters.

F2

Rename the desktop background object that has focus.

Shift- F10

Open the popup menu for the desktop background object that has focus.

Ctrl-F10

Open the Desktop Background menu.


3.2.3. Navigating Panels

A panel is an area from which you can run special programs, applications, and panel applications. The most common panel is the panel that stretches the full width of the bottom edge of the desktop. The following table lists the keyboard shortcuts that you can use to navigate panels and panel objects.

Keys

Function

Ctrl-Alt-Tab

Give focus to a panel. This keyboard shortcut displays a popup window with icons that represent the desktop background, panels, and drawers. Press and hold Ctrl-Alt and continue to press Tab to switch the focus between the desktop background, panels, and drawers.

You can customize this keyboard shortcut.

Tab

Give focus to the next object on the panel.

F10

Open the Applications menu when the Menu Panel has focus. Continue to press F10 to switch focus between the Applications menu and the window list.

spacebar

Activate a panel object; for example, open a menu or start a launcher (icon shortcut).

Shift-F10

Open the panel object popup menu.

Ctrl-F10

Open the panel popup menu.


3.2.3.1. Moving Panel Objects

You can move a focused panel object to a different location on a panel or drawer, or you can move the object to the next panel. To move a panel object, perform the following steps:

  1. Press Tab to give focus to the object.

  2. Press Shift-F10 to open the panel object popup menu.

  3. Use the arrow keys to select the Move menu item.

  4. Use the keyboard shortcuts that are listed in the following table to perform the move operation:

    Keys

    Function

    arrow keys

    Move the object left/right on a horizontal panel, or up/down on a vertical panel.

    Shift + arrow keys

    Move the object with focus, swapping positions with any other objects encountered.

    Ctrl + arrow keys

    Move the object, swapping positions with any other objects that you encounter in the move.

    Tab

    Move the object to the next panel.

    spacebar

    Complete the move operation.

The following examples demonstrate the effect of different move operations on the objects in a panel:

Illustration

Description

Show a panel with three panel objects before a move operation takes place.

Shows the effect of using the arrow keys to move the Geyes panel application on the panel. You can use the arrow keys to move the panel application left or right until you meet the next panel object.

Shows the effect of using Shift + arrow keys to move the Geyes panel application on the panel. You can use the Shift + arrow keys to push the Volume Control and Help panel objects ahead of the object that you are moving.

Shows the effect of using Ctrl + arrow keys to move the Geyes panel application on the panel. You can use the Ctrl + arrow keys to swap positions with the Volume Control and Help panel objects as you meet the objects.

Note

Panel applications that are Locked cannot be moved. To unlock a panel application, use the panel object menu and deselect the Lock to Panel option.


3.2.3.2. Navigating Drawers

A drawer is a collapsible extension of a panel. The following table lists the keyboard shortcuts that you can use to navigate into and out of drawers. When you open a drawer, you can navigate the contents of the drawer in the same way as you navigate a panel. See Section 3.2.3 for information about how to navigate a panel.

Keys

Function

spacebar

Open or close the drawer that has focus.

arrow keys

Navigate into the drawer that has focus.

Esc

Close the drawer and give focus to the drawer object on the panel.


3.2.3.3. Navigating Panel Menus

The following table lists the keyboard shortcuts that you can use to navigate menus on panels:

Keys

Function

spacebar

Open the menu that has focus.

arrow keys

Navigate the menu.

spacebar

Select a menu item.

Shift-F10

Open the popup menu associated with a menu item (if one exists).

Esc

Close a menu.


3.2.3.4. Navigating Panel Applications

A panel application is a small application that resides on a panel. You can navigate to all panel applications and open the panel application popup menu from the keyboard. However, if the panel application does not contain controls that you can give focus to, you cannot navigate the controls in the panel application. The following table lists the keyboard shortcuts that you can use to navigate panel applications.

Keys

Function

spacebar

Activate the panel application control that has focus, if applicable. Not all panel applications contain controls that you can activate. If the panel application does not contain a control that you can activate, the spacebar does nothing.

arrow keys

Navigate the controls on the panel application.

Shift-F10

Open the panel application popup menu. To navigate the menu, use the standard keyboard shortcuts for navigating menus. See Section 3.2.9.1 for information about how to navigate menus.


3.2.4. Navigating Workspaces

A workspace is a discrete area in which you can work. You can have many workspaces on your desktop and you can switch from one workspace to another. Each workspace can contain different windows and processes. The following table lists the keyboard shortcuts that you can use to navigate workspaces:

Keys

Function

Ctrl-Alt + arrow keys

Give focus to the next or previous workspace. This keyboard shortcut displays a popup window with icons that represent the workspaces. Press and hold Ctrl-Alt and continue to press the arrow keys to switch the focus between the workspaces.

You can customize this keyboard shortcut.

Ctrl-Shift-Alt + arrow keys

Move the window that has focus to the next or previous workspace.

You can customize this keyboard shortcut.


3.2.5. Navigating Windows

The following sections describe the keyboard shortcuts that you can use to navigate windows. A window is a rectangular frame on your screen that displays an application.

Note

You can customize all of the keyboard shortcuts that are associated with navigating windows. See Section 3.2.4 for more information.


3.2.5.1. Giving Focus to Windows

Before you can use or modify a window, you must give focus to the window. The following table lists the keyboard shortcuts that you can use to give focus to a window:

Keys

Function

Alt-Tab

Display a popup window with icons that represent each window. Press and hold Alt and continue to press Tab to move through the windows until you reach the window you want to have focus.

Alt-Esc

Raise each window in turn until you reach the window you want.


3.2.5.2. Controlling Windows

When a window has focus, you can perform various actions on the window. The following table lists the keyboard shortcuts that you can use to control the window that has focus:

Keys

Function

Alt- spacebar

Open the Window menu.

Alt-F4

Close the window.

Solaris: Open

Linux: Alt-F9

Minimize the window.

Alt-F10

Maximize the window.

Alt-F5

Restore a maximized window to its original size.


3.2.5.3. Moving Windows

When a window has focus, you can move the window around the screen. The following table lists the keyboard shortcuts that you can use to move a window:

Keys

Function

Alt-F7

Start the move operation. The mouse pointer changes to a cross.

arrow keys

Move the window 10 pixels at a time in the direction of the arrow key.

Ctrl + arrow keys

Move the window one pixel at a time in the direction of the arrow key.

Shift + arrow keys

Move the window in the direction of the arrow key and align it with the edge of the nearest window, panel or screen edge.

spacebar

Complete the move operation, leaving the window in the current position.

Esc

Cancel the move operation, restoring the window to its original position.


3.2.5.4. Resizing Windows

When a window has focus, you can increase or decrease the size of the window. The following table lists the keyboard shortcuts that you can use to resize the window that has focus:

Keys

Function

Alt-F8

Start the resize operation.

arrow keys

Resize the window in the direction of the arrow key.

spacebar

Complete the resize operation, leaving the window at the current size.

Esc

Cancel the resize operation, restoring the window to its original size.


3.2.5.5. Navigating Paned Windows

A paned window is a window that is split into two or more panes. Help Browser is an example of an application that uses paned windows.

The following table describes the keyboard shortcuts that you can use to navigate paned/split windows:

Keys

Function

F6

Give focus to the next pane. The system gives focus to the control that last had focus in the pane.

F8

Give focus to the first resize handle in the window. The resize handle is displayed between the panes and enables you to resize the panes. Press F8 again to give focus to the next resize handle.

When the resize handle has focus, you can use the keyboard shortcuts that are listed in the following table to modify the paned window:

Keys

Function

arrow keys

Move the resize handle by a small amount.

Ctrl + arrow keys

Move the resize handle by a large amount.

Home

Contract the pane to the minimum size allowed.

For vertical panes, reduces the size of the pane to the left of the resize handle to the minimum size allowed.

For horizontal panes, reduces the size of the pane above the resize handle to the minimum size allowed.

End

Expand the pane to the maximum size allowed.

For vertical panes, increases the size of the pane to the left of the resize handle to the maximum size allowed.

For horizontal panes, increases the size of the pane above the resize handle to the maximum size allowed.

spacebar

Set the position of the resize handle and return focus to the last control that had focus.

Esc

Reset the position of the resize handle to the original position and return focus to the last control that had focus.


3.2.6. Navigating Applications

An application is any program, utility, or other software package that you run on your desktop. Applications contain standard user interface components:

Windows

A window is a rectangular frame on your screen that displays an application. See Section 3.2.5 for information about how to navigate windows.

Dialogs

A dialog is a popup window which displays information or accepts input from the user. See Section 3.2.6.2 for information about how to navigate dialogs.

Controls

A control is any user-interactive screen element. Examples of controls include buttons, check boxes, menus, and text boxes. See Section 3.2.9 for detailed information about how to navigate the different types of controls that are available.

This section of the manual describes the essential keyboard shortcuts that you can use in applications and dialogs.


3.2.6.1. Essential Keyboard Shortcuts for NavigatingApplications

Since there are so many applications that you can use in the GNOME Desktop, this manual does not describe all the custom keyboard shortcuts that you can use with each individual application. However, the basic keyboard shortcuts are common to all applications.

Access keys are another way to quickly navigate applications with the keyboard. An access key is identified by an underlined letter on a menu or control. In some cases, you must press Alt in combination with the access key to perform an action.

The following table lists the essential keyboard shortcuts that you can use to navigate applications:

Keys

Function

F10

Open the first menu on the application menubar.

Alt + access key

Open the menu that is associated with the access key.

access keys

Select the menu item that is associated with the access key.

left arrow and right arrow

Switch focus between the menus on the menubar.

up arrow and down arrow

Move focus into a menu.

Esc

Close the open menu and give focus to the control that had focus before the menubar.

Ctrl-O

Open the file selector dialog.

Ctrl-S

Open the Save dialog.

Ctrl-L

Open a Location dialog, enabling you to type the name of a file that you want to open or save.


3.2.6.2. Essential Keyboard Shortcuts for Navigating Dialogs

The following table lists the essential keyboard shortcuts that you can use to navigate dialogs:

Keys

Function

Alt-access key

Activate or select a control.

Tab

Give focus to the next control.

Ctrl-Page Up

Move to the next page/tabbed section of the dialog.

Ctrl-Page Down

Move to the previous page/tabbed section of the dialog.

Esc

Close and/or cancel the dialog.

Return

Perform the default action for the dialog. The default action will usually apply any changes and close the dialog.


3.2.7. Navigating the File Manager

By default, the file manager operates in Spatial mode. This mode uses separate windows for each folder. Conversely, Browser mode will reuse the same window for each folder.

Note

For more information about different modes for the file manager, see the user guide.


3.2.7.1. Navigating Folders

The following table describes the keyboard shortcuts that enable you to navigate folders in the file manager:

Keys

Function

arrow keys

Select the next or previous file or folder in the direction of the arrow key.

Ctrl + arrow keys

Give focus to the next or previous file or folder but do not select the item. This allows multiple, non-contiguous blocks of files to be selected.

spacebar

Open the focused file or folder.

Ctrl + spacebar

Select the item that currently has focus.

A sequence of characters that matches the first n characters of a filename.

Select the first file or folder that starts with the specified sequence of characters.

Home

Select the first file or folder within the current folder.

End

Select the last file or folder within the current folder.

backspace

Open the current folder's parent folder.


3.2.7.2. Navigating Browser Window Components

When operating in Browser mode, the file manager window contains several components, with keyboard shortcuts defined to navigate each component:

Keys

Function

F6

Switch focus between the side pane and the view pane.

Shift-F10

Open the side pane popup menu.


3.2.8. Navigating Help Content in Caret Navigation Mode

The following table describes how to navigate HTML-based help content in caret navigation mode in the Yelp help browser. Caret navigation is a mode of operation in an application which enables you to use the keyboard to navigate and select text.

Keys

Function

F7

Switch to caret navigation mode.

left arrow

Move one character to the left.

right arrow

Move one character to the right.

up arrow

Move up one line.

down arrow

Move down one line.

Ctrl + left arrow

Move to the beginning of the previous word.

Ctrl + right arrow

Move to the end of the next word.

Page Up

Scroll up one page of content.

Page Down

Scroll down one page of content.

Home

Move to the beginning of the current line.

End

Move to the end of the current line.

Shift + arrow keys

Move from the current position to the destination position, selecting all text between the two positions.

Tab

Move focus to the next focusable control.

Shift-Tab

Move focus to the previous focusable control.

Enter

Activate a button or submit a form.


3.2.9. Navigating Standard Elements and Controls

The following sections describe how to navigate and use standard user interface elements and controls from the keyboard.


3.2.9.1. Navigating Menus

The following table lists the keyboard shortcuts that you can use to navigate menus:

Keys

Function

up arrow and down arrow

Give focus to the next or previous menu item on a menu.

right arrow

If the menu item that has focus is a submenu, open the submenu and give focus to the first menu item on the submenu.

If the menu item that has focus is not a submenu, open the next menu on the menubar.

left arrow

If the menu item that has focus is a submenu item, switch the focus back to the submenu.

If the menu item that has focus is not a submenu item, open the previous menu on the menubar.

Return

Select the focused menu item and close the open menus.

access key

Select the menu item that is associated with the access key and close the menu.

spacebar

Select the focused menu item and close the menu except when the menu item is a check box or radio button.

Esc

Close the menu.


3.2.9.2. Navigating Buttons

A button is a control that you use to start an action. Most buttons are rectangular and contain a text label.

Figure 3-1. Sample Button

The following table lists the keyboard shortcuts that you can use to navigate buttons:

Keys

Function

spacebar

Activate the button that has focus. This is the equivalent of clicking on the button.

Return

Activate the button that has focus or, if no button has focus, perform the default action for the dialog.


3.2.9.3. Navigating Radio Buttons

A radio button is a control that you use to select one of several mutually-exclusive options.

Figure 3-2. Sample Radio Button

The following table lists the keyboard shortcuts that you can use to navigate a set of radio buttons:

Keys

Function

arrow keys

Select the next or previous radio button and deselect the other radio buttons in the group.


3.2.9.4. Navigating Check Boxes

A check box is a control that you use to select or deselect an option.

Figure 3-3. Sample Check Box

The following table lists the keyboard shortcuts that you can use to navigate a check box:

Keys

Function

spacebar

Select or deselect the check box.


3.2.9.5. Navigating Text Boxes

Text boxes are controls in which you type text.

Figure 3-4. Sample Single Line Text Box

The following table lists the keyboard shortcuts that you can use to navigate a single line text box:

Keys

Function

left arrow

Position the cursor one character to the left.

right arrow

Position the cursor one character to the right.

Ctrl -left arrow

Position the cursor at the start of the current word. Press and hold Ctrl and continue to press left arrow to position the cursor at the start of the previous word.

Ctrl-right arrow

Position the cursor at the end of the current word. Press and hold Ctrl and continue to press right arrow to position the cursor at the end of the next word.

Home

Position the cursor at the start of the line.

End

Position the cursor at the end of the line.

Shift-left arrow or right arrow

Select one character at a time to the left or right of the cursor.

Shift-Ctrl-left arrow or right arrow

Select one word at a time to the left or right of the cursor.

Shift-Home

Select all text to the left of the cursor.

Shift-End

Select all text to the right of the cursor.

Ctrl-A

Select all text in the text box.

In addition to the keyboard shortcuts listed in the previous table, use the keyboard shortcuts in the following table to navigate multi-line text boxes:

Keys

Function

Page Up

Position the cursor at the top of the current view. Press Page Up again to position the cursor at the top of the previous view.

Page Down

Position the cursor at the end of the current view. Press Page Down again to position the cursor at the end of the previous view.

Ctrl-up arrow

Position the cursor at the start of the current paragraph. Press and hold Ctrl and continue to press the up arrow key to position the cursor at the start of the previous paragraph.

Ctrl-down arrow

Position the cursor at the end of the current paragraph. Press and hold Ctrl and continue to press the down arrow key to position the cursor at the end of the next paragraph.

Ctrl-Page Up

Position the cursor one view width to the left.

Ctrl-Page Down

Position the cursor one view width to the right.

Ctrl-Home

Position the cursor at the start of the text box.

Ctrl-End

Position the cursor at the end of the text box.

Ctrl-Tab

Give focus to the next control on the dialog.

Shift-Page Up

Select the text to the start of the current view. Press and hold Shift and continue to press Page Up to extend the selection to the start of the previous view.

Shift-Page Down

Select the text to the end of the current view. Press and hold Shift and continue to press Page Down to extend the selection to the end of the next view.

Shift-Home

Select the text to the start of the line.

Shift-End

Select the text to the end of the line.

Shift-Ctrl-up arrow

Select the text to the start of the paragraph, then to the start of the previous paragraph.

Shift-Ctrl-down arrow

Select the text to the end of the paragraph, then to the end of the next paragraph.

Shift-Ctrl-Home

Select the text to the start of the text box.

Shift-Ctrl-End

Select the text to the end of the text box.


3.2.9.6. Navigating Spin Boxes

A spin box is a control that allows you to type a numeric value or select a value from a list of all possible values.

Figure 3-5. Sample Spin Box

The keyboard shortcuts that you use to navigate the text box area of a spin box are listed in Section 3.2.9.5. The following table lists the keyboard shortcuts that you can use to navigate the up and down arrows in the spin box:

Keys

Function

up arrow or down arrow

Increase or decrease the value of the spin box by a small amount.

Page Up or Page Down

Increase or decrease the value of the spin box by a large amount.


3.2.9.7. Navigating Drop-Down Lists

A drop-down list is a control that you use to select one of several available items. The drop-down list contains a button that you use to display the available items.

Figure 3-6. Sample Drop-Down List

The following table lists the keyboard shortcuts that you can use to navigate a drop-down list:

Keys

Function

spacebar

This key performs one of the following functions:

  • If the drop-down list is not open, this key opens the drop-down list.

  • If the drop-down list is open, this key accepts the current selection and closes the list.

up arrow

Select the previous list item.

down arrow

Select the next list item.

Esc

Close the list without changing the selection.


3.2.9.8. Navigating Drop-Down Combination Boxes

A drop-down combination box is a text box with a drop-down list attached.

Figure 3-7. Sample Drop-Down Combination Box

When the text box has focus, use the keyboard shortcuts that are listed in Section 3.2.9.5 to navigate the text box area. When the text box has focus, you can also use the keyboard shortcuts in the following table to navigate the drop-down list area:

Keys

Function

up arrow

Select the previous item from the drop-down list without displaying the list.

down arrow

Select the next item from the drop-down list without displaying the list.

Ctrl-down arrow (Solaris only)

Open the drop-down list.

When the drop-down list has focus, you can use the keyboard shortcuts that are listed in the following table to navigate the drop-down list:

Keys

Function

up arrow

Select the previous list item.

down arrow

Select the next list item.

Home

Select the first item in the list.

End

Select the last item in the list.

Page Up

Select the item at the top of the current list view.

Page Down

Select the item at the bottom of the current list view.

spacebar

Accept the current selection and close the drop-down list.

Ctrl-Page Up

Scroll to the left of the list, if required.

Ctrl-Page Down

Scroll to the right of the list, if required.


3.2.9.9. Navigating Sliders

A slider is a control that you use to set a value in a continuous range of values.

Figure 3-8. Sample Slider

The following table describes the keyboard shortcuts that you can use to navigate a slider:

Keys

Function

left arrow or up arrow

Move the slider left or up by a small amount.

right arrow or down arrow

Move the slider right or down by a small amount.

Page Up

Move the slider left or up by a large amount.

Page Down

Move the slider right or down by a large amount.

Home

Move the slider to the maximum value.

End

Move the slider to the minimum value.


3.2.9.10. Navigating Tabbed Sections

Figure 3-9. Sample Dialog with Tabbed Sections

Windows and dialogs are sometimes divided into logical sections that are displayed one section at a time on the window or dialog. The overall control is referred to as a notebook or tabbed panel. The divisions are called panels, pages, or tabs, and are sometimes collectively referred to as a tabstrip or notebook header. Each individual tab is identified by a text label.

The following table lists the keyboard shortcuts that you can use to navigate the tabbed sections of a window or dialog when a tabstrip has focus:

Keys

Function

left arrow

Give focus to the previous tabbed section.

right arrow

Give focus to the next tabbed section.

Tab orCtrl-down arrow

Give focus to the first control in the active section.

The following table lists the keyboard shortcuts that you can use to navigate a window or dialog when a control within a section has focus:

Keys

Function

Ctrl-Page Up or Ctrl-Alt-Page Up

Give focus to the previous section.

This keyboard shortcut does not work if the focused control uses Ctrl-Page Up for another purpose.

Ctrl-Page Down or Ctrl-Alt -Page Down

Give focus to the next section.

This keyboard shortcut does not work if the focused control uses Ctrl-Page Down for another purpose.

Ctrl-Tab

Give focus to the next control outside the sections.


3.2.9.11. Navigating Lists

The following table lists the keyboard shortcuts that you can use to navigate multi-column lists when a column header has focus:

Keys

Function

left arrow or right arrow

Give focus to the previous or next column header.

spacebar

Activate the header. This action usually sorts the list by the column header.

Tab

Give focus to the list contents.

The following table lists the keyboard shortcuts that you can use to navigate lists when the list area has focus:

Keys

Function

arrow keys

Select the next or previous row or column.

Page Up

Select the top row of the list contents that are currently in view. Press Page Up again to select the top row of the previous view.

Page Down

Select the bottom row of the list contents that are currently in view. Press Page Down again to select the bottom row of the next view.

Home

Select the first row in the list.

End

Select the last row in the list.

Shift + arrow keys

For lists that support multi-line selections, add the next or previous row or column to the current selection.

For lists that only allow single line selections, select the next or previous row or column.

Shift-Page Up

Select all the rows between the current selection and the top row of the view.

Shift-Page Down

Select all the rows between the current selection and the bottom row of the view.

Shift-Home

Select all the rows between the current selection and the first row in the list.

Shift-End

Select all the rows between the current selection and the last row in the list.

Ctrl + arrow keys

Give focus to the next row or column without extending the selection. Further items can be selected by pressing spacebar.

Ctrl-Page Up

Give focus to the top row in the view without extending the selection.

Ctrl-Page Down

Give focus to the bottom row in the view without extending the selection.

Ctrl-Home

Give focus to the first row in the list without extending the selection.

Ctrl-End

Give focus to the last row in the list without extending the selection.

Return

Activate the item(s).

Ctrl-A

Select all rows (for lists that support multi-line selections).

Shift-Tab

Give focus to the column header, if applicable.


3.2.9.12. Navigating Trees

A tree is a user interface control that contains sections that you can expand and collapse. A tree usually represents a hierarchical structure.

Figure 3-10. Sample Tree Structure

To navigate trees, you can use the same keyboard shortcuts that are listed in Section 3.2.9.11. In addition, the following table lists the keyboard shortcuts you can use for the tree items:

Keys

Function

+ (plus)

Expand the focused item.

- (minus)

Collapse the focused item.

backspace

Select the parent item.

Ctrl-F

Display a search dialog, allowing you to type the name of the tree item that you want to find. Not all trees support searching.


3.2.10. Customizing Your Keyboard Shortcuts

Use the Keyboard Shortcuts preference tool to display the default keyboard shortcuts that you use to navigate the GNOME Desktop. You can customize the default keyboard shortcuts to meet your requirements. You can also create hot keys (keyboard shortcuts which start applications).

To start the Keyboard Shortcuts preference tool, choose System->Preferences ->Keyboard Shortcuts . The Desktop shortcuts table lists the keyboard shortcuts that are associated with each action.


3.2.10.1. Customizing Keyboard Shortcuts on Solaris Systems

To customize a keyboard shortcut on a Solaris system, perform the following steps:

  1. Click on the action for which you want to customize the keyboard shortcut. The row is highlighted.

  2. Click on the keyboard shortcut in the Shortcut column. The text "Type a new accelerator, or press Backspace to clear" is displayed in the Shortcut column.

  3. Press the keys that you want to associate with the action. The new keyboard shortcut is displayed in the Shortcut column.

To disable a keyboard shortcut, perform the following steps:

  1. Click on the action for which you want to disable the keyboard shortcut. The row is highlighted.

  2. Click on the keyboard shortcut in the Shortcut column. The text "Type a new accelerator, or press Backspace to clear" is displayed in the Shortcut column.

  3. Press the backspace. The keyboard shortcut is disabled.


3.2.10.2. Customizing Keyboard Shortcuts on Linux Systems

To customize a keyboard shortcut on a Linux system, perform the following steps:

  1. Click on the action for which you want to customize the keyboard shortcut. The row is highlighted and the text "Type a new accelerator, or press Backspace to clear" is displayed in the Shortcut column.

  2. Press the keys that you want to associate with the action. The new keyboard shortcut is displayed in the Shortcut column.

To disable a keyboard shortcut, perform the following steps:

  1. Click on the action for which you want to disable the keyboard shortcut. The row is highlighted and the text "Type a new accelerator, or press Backspace to clear" is displayed in the Shortcut column.

  2. Press the backspace. The keyboard shortcut is disabled.


Chapter 4. Low Vision or Blindness

From low vision to blindness, the range of visual limitations is broad. Symptoms of low vision include dimness, haziness, extreme far-/near-sightedness, color blindness, and tunnel vision, among others. People with these disabilities are concerned with being able to see text or images on a computer screen and being able to perform tasks that require eye-hand coordination, such as moving a computer mouse. Text size and color can make a big difference in legibility for people with low vision.

The technologies that can assist those with low vision or blindness are:

  • Screen Magnifier - this is like a magnifying glass. People using them are able to control what area of the computer screen they want enlarged, and can move the magnifier to view different areas of the screen. They are also known as screen enlargers or large print programs.

  • Screen Reader - this makes on-screen information available as synthesized speech and/or a refreshable Braille display. They generally only translate text-based information. Graphics and other non-textual objects can be translated if there is alternative text describing the item. They are also known as blind access utilities or screen reviewers.

  • Desktop Appearance Enhancement - users can configure the desktop to be easy to read; for example, by increasing text size and using high-contrast themes.


4.1. Screen Reader and Magnifier

The Orca Screen Reader and Magnifier application enables users with limited or no vision to use the GNOME Desktop and associated applications. Orca provides the following functionality:

  • Screen Reader

    The screen reader enables non-visual access to standard applications in the GNOME Desktop by using speech and Braille output.

  • Magnifier

    The magnifier provides automated focus tracking and full-screen magnification to aid low-vision users.

The following sections provide information about Orca and how to use it.


4.1.1. Introduction to Orca

4.1.1.1. What is Orca?

Orca is a flexible, extensible, and powerful assistive technology for people with visual impairments. Using various combinations of speech synthesis, Braille and magnification, Orca helps provide access to applications and toolkits that support the AT-SPI (e.g., the GNOME Desktop). Orca is also free open source software.


4.1.1.2. Why the name Orca?

One of the first DOS screen readers was Flipper, made by Omnichron Corporation in Berkeley, CA. It was named Flipper in part because the blind wife of the programmer envisioned computers as being programmed by flipping switches (an accurate image of a bygone era). Then came another DOS screen reader, this one from Henter-Joyce in Florida - "Jobs Access With Speech" (or JAWS). And so on....

Although no obvious connection exists between blindness and creatures from the sea, there is certainly a naming tradition for screen-reader software. Hence Orca, which is a lot tougher-sounding than Nemo, Ariel, Willy, or Mr. Limpet.


4.1.1.3. What's the schedule?

Orca is part of the GNOME platform and Orca's releases are coupled with the releases of the GNOME platform.


4.1.1.4. How do I request a new feature?

Bugs and feature/enhancement requests (RFEs) should be reported to the GNOME Bug Tracking System . Patches are always welcome, and instructions for creating patches can be found in the GNOME Introduction to Subversion (SVN) .


4.1.1.5. Where is the discussion list?

You can get in touch with developers and other users by sending an e-mail to the Orca mailing list ( Archives).


4.1.1.6. Is Braille supported?

Yes! Braille is supported via BrlTTY and it is tightly integrated with Orca. BrlTTY offers support for nearly every refreshable Braille display known to man. Refer to the Braille page for more information.


4.1.1.7. Are Grade 2 Braille contractions supported?

Yes, Orca fully supports contracted Braille output.


4.1.1.8. What voices are available?

Orca provides interfaces to both gnome-speech and emacspeak speech services. As such, the available voices for Orca are only restricted by the speech engines supported by the available speech services. For free speech engines, you typically have a choice of the eSpeak, Festival, and FreeTTS speech engines. For commercial engines, you have a choice of additional engines such as Fonix DECtalk, Loquendo, Eloquence, Cepstral and IBMTTS, with others on the way. Periodically check the gnome-speech package for more progress in this area.


4.1.1.9. What languages are supported?

The GNOME translation teams are composed of many passionate volunteers from around the world. These teams do a great job and keep an up-to-date status report. See the Orca translation status page for the large number of languages into which Orca has been translated.

Note: support for a language also depends on the speech synthesis engine also supporting the same language.


4.1.1.10. How well does magnification work?

Orca currently uses the gnome-mag magnification service. gnome-mag has incorporated support for smoother full-screen magnification, which relies upon newer extensions in the X Window System server. These extensions do not always function well on all platforms, so smooth full-screen magnification may not always work.


4.1.1.11. How is web access coming along?

Orca targets the Firefox web browser (version 3) for providing accessible web browsing. Both the Orca and Firefox teams are fully dedicated in this cooperative effort.


4.1.2. Using Orca

4.1.2.1. Initial Setup

When you run Orca for the first time, it will automatically enter setup mode. If you want to run setup at some later point, you can pass the --setup option to Orca the next time you run it. Furthermore, while Orca is running, you can press Insert-Space to bring up the Orca setup window. Finally, Orca provides a text setup utility that you can start by passing the --text-setup option to Orca. All of these options will create a ~/.orca/user-settings.py file that holds your preferences and will also enable the accessibility infrastructure. You need to log out and log back in for the new settings to take effect.


4.1.2.2. How do I run Orca?

Run Orca by typing orca in a terminal session window. You can do so from a virtual console window if you do not yet have access to the GUI. With the GUI installed you can also press Alt-F2 to bring up the Run dialog and then enter orca as the command (followed by any optional parameters). Orca will automatically enter text setup mode if you run it from a virtual console window or your GUI environment is not yet set up for accessibility.


4.1.2.3. Quitting Orca

To quit Orca, press Insert-Q. A confirmation dialog will appear. Select Yes to quit. If the system seems unresponsive, you can try a few things:

  • Run orca --quit from a terminal window, such as a virtual console; press Ctrl-Alt-F1 (on most Linux platforms) to get to a virtual console, enter your commands, and then use Alt-F7 to get back to the desktop. This will kill the Orca process and reclaim system resources. You can then rerun Orca using the previously outlined methods.

    Press Ctrl-Alt-Backspace to end your login session and get back to the graphical login prompt (not implemented in all Linux distributions).


4.1.3. Customizing Orca

4.1.3.1. How do I define my own keybindings?

You can redefine your key bindings for Orca in two main ways. The first way is to choose between the Desktop and Laptop layouts, which can be selected on the General page of the Orca configuration dialog (press Insert-Space to bring up Orca Preferences). For more refined control, you can set individual key bindings on the Key Bindings page of the Orca configuration dialog.


4.1.3.2. Use a keyboard command to make Orca speak or Braille-output the current date and time

Place the following lines in ~/.orca/orca-customizations.py. If this file doesn't exist yet, go ahead and create it.

import orca.input_event
import orca.keybindings
import orca.orca
import orca.speech
import orca.braille
import re


myKeyBindings = orca.keybindings.KeyBindings()


def sayTime(script, inputEvent=None):
  import time
  message = time.strftime("%a, %d %b %Y %H:%M:%S", time.localtime())
  orca.speech.speak(message)
  orca.braille.displayMessage(message)
  return True


sayTimeHandler = orca.input_event.InputEventHandler(
  sayTime,
  "Presents the time.")


myKeyBindings.add(orca.keybindings.KeyBinding(
  "d",
  1 << orca.settings.MODIFIER_ORCA,
  1 << orca.settings.MODIFIER_ORCA,
  sayTimeHandler))


orca.settings.keyBindingsMap["default"] = myKeyBindings

Note that in this case Insert-D will be used to report current information about the time and date.


4.1.3.3. How do I set up my own custom scripts?

Create an empty file named ~/.orca/orca-scripts/__init__.py and place your custom scripts in ~/.orca/orca-scripts , Orca will pick up any scripts from there before looking in the installed area.


4.1.3.4. Orca Configuration

The Orca configuration dialog allows you to customize the behavior and features of Orca, such as speech, Braille, and magnification. For example, you can select which speech synthesis engine you want to use, whether Braille is enabled or not, and which magnification preferences you want. You can select between Laptop/Desktop keyboard layouts and you can also examine and modify the existing keyboard layout with granular control. To bring up the Orca configuration dialog, press <ORCA MODIFIER>-Space, where <ORCA MODIFIER> is Insert when you use the Desktop key bindings, and Caps Lock when you use the Laptop key bindings.

The Orca configuration dialog is a multi-tab container for several pages, each of which is described in the following sections.


4.1.3.4.1. General Page

The General page allows you to customize general aspects of Orca. These include the following:


4.1.3.4.1.1. Keyboard Layout

The keyboard layout section lets you choose between a small keyboard layout (Laptop) or large keyboard layout with a numeric keypad (Desktop). If you choose Laptop the Orca system key is CapsLock; for the Desktop layout the system key is Insert.


4.1.3.4.1.2. Show Orca Main Window

The Orca main window provides you with a graphical way to display the Orca configuration dialog (also obtained by Insert-Space). Many users do not like the Orca main window because it shows up in the window manager's tab order when you press Alt-Tab to switch windows. By deselecting the Show Orca Main Window option, you can tell Orca to not show its main window.


4.1.3.4.1.3. Quit Orca without Confirmation

Normally when you press Insert-Q or press the Quit button in the Orca main window, a confirmation dialog will prompt if you really want to quit. Unchecking this option prevents the confirmation window from appearing.


4.1.3.4.1.4. Disable gksu keyboard grab

When running system administration commands from the launch menu, many distributions use an application known as gksu to authorize the user to run these commands (gksu is the dialog that asks you for your password). When it runs, gksu enables what is known as a "keyboard grab," which is a feature to prevent keyboard actions from going to any other application on the desktop, including Orca. The result of a keyboard grab is that Orca will not receive any keyboard events, preventing Orca from functioning normally.

By selecting the Disable gksu Keyboard Grab button, you will turn off the keyboard grab behavior, allowing Orca to function normally with system administration applications.

Note

The keyboard grab is a security attempt by gksu to prevent malicious applications from "sniffing" the keyboard and obtaining your password. Please be advised that disabling gksu's keyboard grab feature can expose you to such nefarious behavior.

If you do not feel comfortable with this, you can always use the root account for system administration purposes. To do so, you need to enable the root account for login, and then log out and back in again as root whenever you want to perform a system administration command.


4.1.3.4.1.5. Present Tooltips

When checked, this option will tell Orca to present information about tooltips when they appear as the result of mouse hovering. Specific actions to force tooltips to appear, such as pressing Ctrl-F1 when an object has focus, will always result in tooltips being presented, regardless of this setting.


4.1.3.4.2. Speech Page

The speech page allows you to customize how Orca uses speech synthesis.


4.1.3.4.2.1. Enable Speech

The first control of note on the speech page is the Enable Speech check box. This check box toggles whether or not Orca will make use of a speech synthesizer. This option, along with the ability to enable Braille and magnifier support, allows Orca to be tailored to meet the specific needs of a wide variety of users.


4.1.3.4.2.2. Speech System and Speech Synthesizer

The next two controls deal with selecting the speech system and synthesizer. Orca provides support for a growing number of speech systems. At the time of this writing these include GNOME-speech, Emacspeak, and an experimental backend for Speech Dispatcher. Depending on how your machine is configured, you may have all or none of these options. Typically, you will only have GNOME-speech available.

First, determine which speech system you would like to use - GNOME-speech works best at this time. After making your selection, tab to the speech synthesizer combo box and choose from the list of available synthesizers.


4.1.3.4.2.3. Voice Settings

If your synthesizer supports it, Orca can utilize multiple voices in order to identify special cases within an application, such as hyperlinks or uppercase text. The voice settings and person combo boxes can be adjusted to customize these settings to your liking. For example, assume you were using Fonix DECtalk and wanted the Betty voice to denote uppercase. To accomplish this, you could do the following:

  1. Tab to the voice settings combo box, and press the down arrow until the uppercase voice is selected.

  2. Tab to the person combo box, and press the down arrow to choose the Betty voice.

The next three sliders in the tab order allow adjustment of the synthesizer's rate, pitch and volume, respectively.

Note that you can quickly raise/lower the pitch by pressing Insert-Up Arrow and Insert-Down Arrow. You can also modify the speaking rate by pressing Insert-Left Arrow and Insert-Right Arrow.


4.1.3.4.2.4. Punctuation Level

The Punctuation Level radio button group is used to adjust the amount of punctuation spoken by the synthesizer. The available levels are None, Some, Most and All.


4.1.3.4.2.5. Verbosity

The Verbosity setting determines the amount of information that will be spoken in certain situations. For example, if it is set to Verbose, the synthesizer will speak shortcut keys for items in pull-down menus. When it is set to Brief, these shortcut keys are not announced.


4.1.3.4.2.6. Table Row Speech

The table row speech option determines the way in which Orca will read items within tables. The available settings are Speak Current Row or Speak Current Cell. The ability to adjust this behavior can be useful in many situations. For example, consider the process of browsing email messages in Evolution. In this instance it may be preferable to set table speech to Speak Current Row, so arrowing through the list of messages causes all relevant info, such as the sender, subject, and whether the message has attachments, is read automatically. While the current row setting is active, it is still possible to read individual cells by using the left and right arrows.

Note that you can quickly toggle this behavior by pressing Insert-F11.


4.1.3.4.2.7. Speak Indentation

When working with code or editing documents, it is often desirable to be aware of justification as well as indentation. Selecting the Speak Indentation and Justification check box will cause Orca to provide this information.


4.1.3.4.2.8. Speak Blank Lines

Some users desire to hear the word "blank" when navigating through empty lines in a document. Other users do not. If the Speak Blank Lines check box is selected, Orca will announce any blank lines.


4.1.3.4.3. Braille Page

The Braille page allows you to customize various aspects of Braille output. Orca does not automatically start BrlTTY - you typically need to do this yourself, and it usually occurs during OS startup.


4.1.3.4.3.1. Enable Braille Support

The first control on the Braille page is the Enable Braille Support check box. This toggles whether or not Orca will make use of a Braille display. This option, along with the ability to enable Braille and magnifier support, allows Orca to be tailored to meet the needs of a wide variety of users. By default, this check box is enabled. If BrlTTY is not running, Orca will recover gracefully and will not communicate with the Braille display. If you configure BrlTTY later on, you need to restart Orca in order for it to use Braille.


4.1.3.4.3.2. Enable Braille Monitor

Orca's Braille monitor provides an on-screen representation of what takes place on the Braille display. This feature is mostly for demonstration purposes, but is also useful for Orca developers who do not have access to a Braille display.


4.1.3.4.3.3. Abbreviated Role Names

The Abbreviated Role Names check box determines the manner in which role names are displayed and can be used to help conserve real estate on the Braille display. This option is best explained by example:

Let us assume that a slider had focus, and that the abbreviated role names box was not checked. In that case, the word "slider" would be shown on the display, to reflect the fact that the current control was indeed a slider. If the abbreviated role names box was checked, the word "slider" would be abbreviated to "sldr".


4.1.3.4.3.4. Verbosity

The Verbosity radio button group determines the amount of information that will be output to Braille in certain situations. For example, if it is set to Verbose, keyboard shortcut and role name information is displayed. This information is not displayed in Brief mode.


4.1.3.4.4. Key Echo Page

The Key Echo page allows you to specify the behavior of Orca when pressing keys on the page and whether words are spoken as you complete them.


4.1.3.4.4.1. Enable Key Echo

The first control on the key echo page is the Enable Key Echo check box. When this box is checked, five additional check boxes become available. These are Enable Alphanumeric and Punctuation Keys, Enable Modifier Keys, Enable Locking Keys, Enable Function Keys, and Enable Action Keys.

The alphanumeric and punctuation option determines if letter, number and punctuation characters are echoed as you type them.

Modifier keys are those such as Shift, Control, and Alt.

Locking keys include Caps Lock, Scroll Lock, and Num Lock.

Enabling function key echo will announce F1 - F12 when they are pressed.

The action keys group consists of keys that perform some logical action, as Backspace, Return and Tab.


4.1.3.4.4.2. Enable Echo by Word

The last toggle on the Key Echo page is the Enable Echo by Word check box. This option is always available, regardless of whether any of the key echo options are checked. When enabled, whole words are spoken as typing progresses.

In summary, the Key Echo scheme can offer a great deal of flexibility. For example, one user might choose to enable all Key Echo options, while another might prefer to use word echo, but only have locking keys announced.


4.1.3.4.5. Magnifier Page

The magnifier page allows you to enable/disable magnification and specify how magnification is performed.


4.1.3.4.5.1. Enable Magnifier

The first control on the magnifier page is the Enable Magnifier check box. This toggles whether or not Orca will provide magnification. This option, along with the ability to enable speech and Braille support, allow Orca to be tailored to meet the needs of a wide variety of users.


4.1.3.4.5.2. Cursor Settings

  • Enable Cursor

  • Color

  • Custom Size and Width


4.1.3.4.5.3. Cross-Hair Settings

  • Enable Cross-Hair and Size

  • Enable Cross-Hair Clip


4.1.3.4.5.4. Zoomer Settings

  • Scale factor

  • Invert Colors

  • Zoomer Position

    • Top, Left, Right, Bottom

  • Smoothing

  • Mouse Tracking Mode

  • Source Display - X Window System display of what should be magnified. Typically :0.

  • Target Display - X Window System display of where to put the magnified area. Typically :0.


4.1.3.4.6. Key Bindings Page

The key bindings page allows you to examine and modify the key bindings for Orca.


4.1.3.4.6.1. Orca Modifier Key(s)

The first control on the Key Bindings page allows you to examine which key (or keys) acts as the "Orca modifier" (Orca system key). The Orca modifier is the key that you press and hold in conjunction with other keys to give commands to Orca. For Desktop keyboards, the modifier defaults to Insert. For Laptop keyboards, the modifier defaults to the Caps Lock key.

You cannot modify the Orca modifier key(s) using the configuration dialog at this time.


4.1.3.4.6.2. Key Bindings Table

The key bindings table provides a list of Orca operations and the keys that are bound to them.

The "Function" column header is a description of the operation to be performed.

The "Key Binding" header is the primary way to invoke the function from the keyboard. Note that the function description may include the word Orca. This indicates that the Orca modifier key should be held down along with the other key(s).

The "Alternate" header provides an alternate mechanism for invoking the function from the keyboard.

To modify either the "Key Binding" or the "Alternate" bindings, arrow to the cell and press Return. Then, press a key combination and press Return to confirm the new combination. When you do so, the new keystroke will be saved and the check box in the Modified column will indicate that the key binding has been modified.

To undo a modified keybinding, arrow to the modified column, uncheck the checkbox, and press the Apply button (Alt-A).


4.1.3.4.7. Text Attributes Page

Orca will speak known text attribute information about an object when you press Insert-F (Caps Lock-F for Laptop systems).

Because the number of text attributes is large, and not everyone cares about every attribute, the "Text Attributes" tab of the Orca configuration dialog allows you to customize which text attributes will be presented.

On this tab is a text attribute list, where each row consists of three columns:

  1. A checkbox which the user can set to indicate whether this text attribute should be spoken or not.

  2. The name of the text attribute.

  3. An editable "Spoken unless" string value. By default, not all text attributes will have this set. If present, what it means (assuming the user wants this text attribute spoken) is that the value of the attribute will only be spoken if it's a different value than this value.

For example, by default the "underline" text attribute has a value of "none". If the user has this attribute checked and the user presses Insert-F and the text in question is not underlined, then this attribute is not spoken. If you always want this attribute to be spoken regardless of whether the text is underlined, then the attribute should be checked and the "Spoken unless" value cleared.

There is also a Reset button (Alt-R) that will set the list values back to their initial state when the dialog was first displayed.

When you initially display the text attribute pane, all your checked attributes are put at the top of the list. They are given in the order that they will be spoken and output to Braille.

If you decide to check others or wish to adjust the order, there are four buttons to help you do this:

  • Move to Top ( Alt-T) - moves the selected attribute to the top of the list.

  • Move Up One ( Alt-U) - moves the selected attribute up one row.

  • Move Down One ( Alt-D) - moves the selected attribute down one row.

  • Move to Bottom ( Alt-B) - moves the selected attribute to the bottom of the list.

Text attributes can also be set on an individual application basis. The text attribute pane is also part of the application specific settings dialog that is started when you give a particular application focus and press Insert-Ctrl-Space.


4.1.4. Application-Specific Information

4.1.4.1. Accessible Applications

Orca is designed to work with applications and toolkits that support the Assistive Technology Service Provider Interface (AT-SPI). This includes the GNOME Desktop and its bundled applications: OpenOffice, Firefox, and the Java platform. Some applications work better than others, however, and the Orca community continually works to provide superior access to more and more applications.


4.1.4.2. Using Adobe's Acrobat Reader

We are currently working on a script for Adobe's Acrobat Reader, and the initial version has been contributed to Orca v2.17.5. Note that there is still work to do, and we are very encouraged by Adobe's commitment to accessibility.


4.1.4.2.1. Installation

If you get Adobe Acrobat Reader directly from the Adobe site, you may find that the software will not launch. If launched from the Applications menu, it may appear that nothing has happened, or if launched from a terminal window you may receive a long series of syntax error messages. Should this occur, you will need to edit your /usr/bin/acroread file as described in this Ubuntu forum thread.

If you instead choose to install Acrobat Reader from your distribution's packages, be sure to install both acroread and acroread-plugins. Without the plugins package, you will not have the access to the "Reading" category in the Edit-->Preferences dialog.

Note: If you use Ubuntu and cannot locate the acroread package, you will likely need to edit your /etc/apt/sources.list to include the 'multiverse' repository. Then run apt-get update. Having done so, you should then be able to install both acroread and acroread-plugins.


4.1.4.2.2. Enabling Accessibility and Caret Navigation

Once you've installed Reader, you need to enable accessibility:

  1. In the "Accessibility" category of the Edit-->Preferences dialog, make sure Always display the keyboard selection cursor (Alt-D) is checked.

  2. In the "Reading" category of the Edit-->Preferences dialog, make sure Enable Document Accessibility ((Alt-E) is checked.


4.1.4.2.3. Working with Untagged Documents

When you open an untagged document, you will be presented with a dialog box asking you to specify the reading order and the reading mode options. The default reading order is Infer reading order from document . This setting works well for most documents.

The default reading mode will vary depending on the length of the document; for short documents, the default is Read the entire document; for long documents the default is Read currently visible pages only. Orca tends to work better when Read the entire document is selected.

If you find that a document seems to be missing parts of the text, try changing the reading options. To do so, get into the Document menu and select Change Accessibility Reading Options... or use the shortcut Ctrl-Shift-5.


4.1.4.2.4. Page Layout

The best page layout for reading a document with Orca is Single Page. When Continuous is chosen, moving focus to text as the page is scrolling can cause that text not to be read. You can change the page layout to Single Page by getting into the View menu and selecting the Page Layout submenu.


4.1.4.2.5. Navigating Tables

As far as we know there isn't currently a whole lot of keyboard support for tables in Acrobat Reader. We hope Adobe will remedy this soon.

Basically, there are the arrow keys. Their behavior is to move you first within the cell with focus, then to the next cell with data in it. Note that currently, Up and Down Arrow do not seem to move you vertically among cells - at least that has been the experience with the tables we have tried. Instead, Up and Down seem to move you horizontally until you run out of cells on the current row.


4.1.4.3. Making Application-Specific Settings

To customize the settings for a particular application, you will first need to run that application. Make sure the application has focus, then press ORCA_MODIFIER-Control-Space (by default, this will be Insert-Control-Space for the Desktop keyboard layout).

This brings up a tabbed dialog window very similar to the Orca configuration dialog, but with the following differences:

  1. There is no initial General pane.

  2. The Speech System and Speech Synthesizer combo boxes on the Speech pane will be grayed out (made inactive).

  3. Any existing application-specific key bindings will appear at the top of the list on the Key Bindings pane.

  4. There may be a new application-specific settings pane at the end of the set of tabbed panes. Note that pressing the End key from the tab list will get you directly to the right-most tab.

Adjust your application-specific settings in the same way you set your general Orca preferences. For example, you may have Key Echo disabled generally in Orca but would like to specifically have it enabled for the gcalctool (GNOME Calculator) application. Here's where you could easily set that.

When you have your application settings customized the way you want, press the OK button. These settings will be written to your ~/.orca/app-settings directory in a file called <APPNAME>.py, where <APPNAME> is the name of the application.

These files are automatically written by Orca. The contents of the file will be overwritten each time you change your application settings for that application.

If you want to have some extra application-specific settings or code that you don't want to lose, then you should put it in a file called ~/.orca/app-settings/<APPNAME>-customizations.py. This file will be automatically read when the settings for the <APPNAME> application are loaded.

Note that this is an advanced feature that we don't expect many people to use. It's just there if you really want it.

There is currently one known bug (some people would call it a feature) that we are trying to track down and fix:

Note

If you adjust one or more application-specific key bindings, the new values will not take effect until you've pressed the OK button. The work-around is to either restart Orca, or Alt-Tab away to some other application and then Alt-Tab back to the one that you've just changed the key bindings for.


4.1.5. Braille

Orca uses BrlTTY for Braille support. Orca does not automatically start BrlTTY - you typically need to do that yourself, and it is something that is usually done at boot time. Start-up options are described in the BRTLTTY reference manual.

Orca attempts to work with various releases of BrlTTY. It works well with BrlTTY v3.7.2, and we've also been working with the BrlTTY team to get it going for BrlTTY v3.8. The remainder of this document provides information related to using Orca with BRLTTY 3.8.

To get Orca working with BrlTTY v3.8 requires that the Python bindings for BrlAPI are built/installed as part of the BrlTTY build/install process. Below are descriptions of the necessary tasks to do this in Ubuntu and Solaris. For both, you need to first obtain brltty-3.8.tar.gz from the BrlTTY site.


4.1.5.1. BrlTTY 3.8 on Ubuntu

First, configure your build environment to build BrlTTY. Much of this setup is done for you automatically in the Ubuntu distribution with products such as G++ already present. In addition, you must also install tcl, Pyrex, and the Python developer environment. To do this, execute the following commands as root:

apt-get build-dep brltty
apt-get install tcl8.4 python-pyrex python-dev

Then, when you build BrlTTY, avoid configuring the package with --prefix=/usr. Use the standard procedure instead, executing the following commands as root:

gunzip -c brltty-3.8.tar.gz | tar xvf -
cd brltty-3.8
./autogen
./configure
make
make install

Run BrlTTY as root:

/bin/brltty -bauto -d/dev/ttyUSB0

If you want, you can remove the existing /sbin/brltty and replace it with the /bin/brltty, either by copying the /bin/brltty to /sbin/brltty or just by making a symbolic link. Do so at your own risk.


4.1.6. Keyboard Commands

This is the list of common Orca keyboard commands. Note that you can always enter Orca's Learn mode while running Orca by pressing Insert-F1. When in Learn mode, Orca will intercept all keyboard and Braille input events and will tell you what the effect of them would be. To exit Learn mode, press the Escape key. If you are using a laptop computer, you will want to see the laptop keyboard commands page at live.gnome.org.


4.1.6.1. Adjusting Speech Parameters

Insert-Right Arrow: increase speech rate

Insert-Left Arrow: decrease speech rate

Insert-Up Arrow: raise the pitch

Insert-Down Arrow: lower the pitch


4.1.6.2. Flat Review Commands

Numpad-7: Move the flat review cursor to the previous line and read it.

Numpad-8: Read the current line.

Numpad-9: Move the flat review cursor to the next line and read it.

Numpad-4: Move the flat review cursor to the previous word and read it.

Numpad-5: Read the current word.

Numpad-6: Move the flat review cursor to the next word and read it.

Numpad-1: Move the flat review cursor to the previous character and read it.

Numpad-2: Read the current character.

Numpad-3: Move the flat review cursor to the next character and read it.

Numpad-/: Perform a left mouse click at the location of the flat review cursor.

Numpad-*: Perform a right mouse click at the location of the flat review cursor.

Note

The above commands apply when working with objects as well as when working with text. For example, if the flat review cursor were positioned on a menu bar, pressing the "read current line" command (Numpad-8) would speak the names of all visible menus. Similarly, pressing "read next word" would speak the object to the right of the flat review cursor on the same line, or move flat review to the next line if no more objects were found.


4.1.6.3. Bookmark Commands

Alt-Insert-[1-6]: add a bookmark in this numbered slot. If a bookmark already exists it will be replaced.

Insert-[1-6]: go to the position pointed to by the bookmark bound to this numbered slot.

Alt-Shift-[1-6]: "Where am I" information for this bookmark relative to the current pointer location.

Insert-B and Insert-Shift-B: move between the given bookmarks for the given application or page.

Alt-Insert-B: save the defined bookmarks for the current application or page.


4.1.6.4. Miscellaneous Functions

Insert-Numpad-+: "say all" command; reads from the current position of the caret to the end of the document.

Insert-Numpad-Enter: "where am I" command; speaks information such as the title of the current application window as well as the name of the control that currently has focus.

Insert-F1: enter Learn mode (press Escape to exit)

Insert-F: speak font and attribute information for the current character.

Insert-Space: launch the Orca configuration dialog.

Insert-Ctrl-Space: reload user settings and reinitialize services as necessary. Also launch the Orca configuration dialog for the current application.

Insert-S: toggle speech on and off.

Insert-F11: toggle table-reading mode between single cell or entire row.

Insert-Q: quit Orca.


4.1.6.5. Commands for Debugging

Insert-F3: report information on the currently active script.

Insert-F4: cycle through Orca's various debug levels.

Note

In order for the next three commands to be of use, Orca needs to be started from a virtual console or via gnome-terminal. Output is sent only to the console (i.e., it is not sent to speech or Braille).

Insert-F5: prints a debug listing of all known applications to the console where Orca is running.

Insert-F7: prints debug information about the ancestry of the object with focus.

Insert-F8: prints debug information about the current application.


4.1.7. Troubleshooting


4.1.7.2. My desktop has stopped responding. What do I do?

If you can get to a terminal (or press Alt-F2 to open the "Run Command" dialog box), try restarting Orca by issuing another Orca command in a terminal window. This will force any existing Orca process to exit and will then restart Orca. This sometimes has the effect of unhanging the desktop (which is usually due to an ill-behaved application).

If you cannot get to a terminal window, try pressing Ctrl-Alt-Backspace: shut down the X Window System server. This should return you to the login screen.


4.2. Desktop Appearance Enhancement

This chapter describes the methods you can use to change the appearance of the GNOME Desktop in order to enhance the accessibility of the desktop for users with visual impairments.


4.2.1. Customization Options

There are several ways to customize the appearance of the GNOME Desktop to suit your specific needs:

Themes

Themes are the most effective way to change the appearance of the desktop in a consistent manner. See Section 4.2.2 for more information about themes and how to use them to achieve the type of desktop environment that you require.

Desktop and Application-Specific Configuration Settings

You can customize different components of the desktop to achieve the display settings that you require. You can configure the desktop and applications in addition to using themes or as an alternative to themes. See Section 4.2.3 for more information.

The following table summarizes the changes that you can make to the GNOME Desktop and where you can make the changes. This guide does not provide detailed instructions about how to customize the desktop. For detailed instructions about how to use the customization tools that the desktop provides, refer to the Help for each tool or to the User Guide.

Table 4-1. Quick Reference to Customizing the Appearance of the Desktop

To change the...

Use...

Overall appearance of the desktop using high-contrast colors, low-contrast colors, or large print.

The Theme preference tool.

Appearance of the desktop background only.

The Desktop Background preference tool and the file manager Backgrounds and Emblems menu item.

Font displayed on the desktop background and in all desktop applications.

The Font preference tool.

Default font settings of the Text Editor, Terminal or Help application.

Normally these applications use the default application font that is specified in the Font preference tool but can be overridden in the Preferences dialog for the application.


4.2.2. Using Themes to Customize the Desktop

This section describes how to use themes to customize the appearance of the GNOME Desktop.


4.2.2.1. Introduction to Themes

A theme is a group of coordinated settings that specifies how a desktop component or a group of desktop components appears. You can use themes to modify and control the appearance of the desktop in a consistent manner. When you apply a theme, the system modifies many desktop components simultaneously to achieve the desired effect. For example, if you apply a theme that increases the font size across the desktop, the theme also modifies the size of panels and icons on the desktop for optimum compatibility with the font size.

A theme contains settings that affect different parts of the desktop:

Controls

The controls setting for a theme determines the visual appearance of all windows, applications, panels, and panel applications. The controls setting also determines the visual appearance of the GNOME-compliant interface items that appear on windows, applications, panels, and panel applications such as menus, icons, and buttons. Some of the control options that are available in the desktop are designed for special accessibility needs.

Window Border

The window frame setting determines the appearance of the border around windows only.

Icon

The icon setting determines the appearance of icons on panels and on the desktop background.


4.2.2.2. Choosing Themes

To choose a theme, perform the following steps:

  1. Choose System->Preferences->Appearance . The themes are listed under the Theme tab.

  2. Click on a theme in the list box to choose a new theme. The system automatically applies the theme to the desktop.

    There are several themes available that suit different accessibility needs, as described in the following table:

    Table 4-2. Themes Designed for Accessibility Requirements

    Theme Name

    Description

    High Contrast

    Provides dark text on a light background using high-contrast colors.

    High Contrast Inverse

    Provides light text on a dark background using high-contrast colors.

    Large Print

    This theme suggests an increased font size of 18pt. The background and foreground colors are the same as those specified by the Default desktop theme. To apply the suggested font, click on the Apply Font button.

    High Contrast Large Print

    This theme suggests an increased font size of 18pt using dark text on a light background. To apply the suggested font, click on the Apply Font button.

    High Contrast Large Print Inverse

    This theme suggests an increased font size of 18pt using light text on a dark background. To apply the suggested font, click on the Apply Font button.

To view the controls, window frame, and icon settings that are associated with a theme, select a theme in the Theme Preferences dialog, then click on the Theme Details button. The Theme Details dialog contains a tabbed section for each setting category. Each tabbed section lists the options that are available and the current setting for the theme is highlighted.


4.2.2.3. Modifying the Controls Setting for a Theme

To modify the controls setting that is associated with a theme, perform the following steps:

  1. In the Theme Preferences dialog, select the theme that you want to modify.

  2. Click on the Theme Details button. The Theme Details dialog is displayed.

  3. Click on the Controls tab to display the controls options that are available.

  4. Select the controls option that you want to associate with the current theme from the list box, then click Close. The following table lists the controls options that are suitable for accessibility needs:

Table 4-3. Controls Options Designed for Accessibility Requirements

Control Option

Description

HighContrast

Provides dark text on a light background using high-contrast colors.

HighContrastInverse

Provides light text on a dark background using high-contrast colors.

LowContrast

Uses low-contrast colors for the background and foreground text.

LargePrint

Increases the size of controls to accommodate larger fonts. To increase the font size, you must use the Font preference tool. The background and foreground colors are the same as those specified by the Default desktop theme.

HighContrastLargePrint

Provides dark text on a light background using high-contrast colors. Increases the size of controls to accommodate larger fonts. To increase the font size, you must use the Font preference tool.

HighContrastLargePrintInverse

Provides light text on a dark background using high-contrast colors. Increases the size of controls to accommodate larger fonts. To increase the font size, you must use the Font preference tool.

LowContrastLargePrint

Uses low-contrast colors for the background and foreground text. Increases the size of controls to accommodate larger fonts. To increase the font size, you must use the Font preference tool.


4.2.2.4. Modifying the Window Border Setting for a Theme

To modify the window border setting that is associated with a theme, perform the following steps:

  1. In the Theme Preferences dialog, select the theme that you want to modify.

  2. Click on the Theme Details button. The Theme Details dialog is displayed.

  3. Click on the Window Border tab to display the window frame options that are available.

  4. Select the window frame option that you want to associate with the current theme from the list box, then click Close. The Atlanta option is designed for accessibility.


4.2.2.5. Modifying the Icon Setting for a Theme

To modify the icon setting that is associated with a theme, perform the following steps:

  1. In the Theme Preferences dialog, select the theme that you want to modify.

  2. Click on the Theme Details button. The Theme Details dialog is displayed.

  3. Click on the Icons tab to display the icon options that are available.

  4. Select the icon option that you want to associate with the theme from the list box, then click Close. The following table lists the icon options that are suitable for accessibility needs:

Table 4-4. Icon Options Designed for Accessibility Requirements

Icon Option

Description

HighContrast

Provides dark-on-light icons using high-contrast colors.

HighContrastInverse

Provides light-on-dark icons using high-contrast colors.

LowContrast

Uses low-contrast colors for the background and foreground text.


4.2.2.6. Creating Your Own Themes

For information about how to create your own themes, see the System Administration Guide.


4.2.3. Customizing Specific Components of the Desktop

This section describes how to customize specific components of the GNOME Desktop individually.


4.2.3.1. Customizing the Desktop Background

The themes do not affect the desktop background. Therefore, to modify the desktop background to complement your desktop, you must customize the desktop background separately using the Desktop Background preference tool. To start the Desktop Background preference tool, choose System->Preferences->Appearance and choose a background from the Background tab.


4.2.3.2. Customizing Desktop Background Objects

The size of the icons that are displayed on the desktop background is controlled by the File Management preference tool. To change the size of the icons, perform the following steps:

  1. From the File Manager window, choose the Edit->Preferences menu item.

  2. Select the Views tabbed section.

  3. In the Icon View Defaults group, select the zoom level that you require in the Default Zoom Level drop-down list.


4.2.3.3. Customizing Fonts

This section describes how to customize the font settings for the desktop and frequently-used applications.

If you have difficulty with the default font type and font size that is used on the desktop and desktop background, you can customize the font settings to suit your needs.

You can specify individual font settings for the following desktop components and applications:

  • Entire desktop (excluding the desktop background)

  • Desktop background only

  • Terminal

  • Text Editor

  • Help

  • Web Browser


4.2.3.3.1. Customizing Desktop Fonts

The Font preference tool allows you to specify the default fonts for the desktop.

To start the Font preference tool, choose System->Preferences->Appearance. The Fonts tab contains the following options:

Application Font

Click on this button to select a default font to use for the text that is displayed on the desktop, including the text displayed on the windows and dialogs associated with GNOME-compliant applications and panel applications.

Note

If you use the Theme preference tool to select a theme and you click on the Apply Font button, the font that is associated with the theme overrides the font from the Font preference tool.

Document Font

Click on this button to select a font to use for displaying documents.

Desktop Font

Click on this button to select a font to use for the text that is displayed on the desktop background only.

Window Title Font

Click on this button to select a font to use for the text that is displayed in the titlebar area of windows.

Fixed Width Font

Click on this button to select a font to use for editing documents.

Font Rendering

To specify how to render fonts on the desktop, select one of the following options:

  • Monochrome

  • Best Shapes

  • Best Contrast

  • Subpixel Smoothing

Note

If you use large fonts, you may need to change the size of panes in some applications, such as the file manager and Help browser.

For more information about the Font preference tool, see the User Guide.


4.2.3.3.2. Customizing Application Fonts

By default, GNOME applications use the default font specified in the Font preference tool. Some applications allow this default font to be customized. These applications are:


4.2.4. Meeting Specific Accessibility Needs

The following sections summarize the steps you need to take to improve the accessibility of the desktop in a particular area.


4.2.4.1. Achieving a High- or Low-Contrast Desktop

To achieve a high- or low-contrast desktop, perform the following steps:

  1. Use the Theme preference tool to select the high-contrast or low-contrast desktop theme that you require.

  2. Use the Desktop Background preference tool to customize your desktop background as follows:

    • Set the Desktop Wallpaper to No Wallpaper.

    • Set the Desktop Colors to Solid Color.

    • Select a background color that suits your needs.

  3. In the Terminal application, ensure that the Use colors from system theme option is selected in the Colors tabbed section of the Editing Profile dialog.

  4. In the gedit (Text Editor) application, ensure that the Use default theme colors option is selected in the Fonts & Colors tabbed section of the Preferences dialog.


4.2.4.2. Achieving a Large Print Desktop

To achieve a large-print desktop, perform the following steps:

  1. Use the Theme preference tool to select the Large Print theme.

  2. Click on the Apply Font button to increase the size of the font that is used on the desktop and on window frames.

  3. Use the Desktop Font option in the Font preference tool to increase the font that is displayed on desktop background objects.

  4. Increase the font size that is used to display the contents of the Terminal application window.

  5. If the Use default theme font option is selected in the gedit (Text Editor) Preferences dialog, gedit uses the font size that is specified in the large-print theme that you selected. However, if the Use default theme font option is not selected, increase the font size that is used to display the contents of the gedit text editor window. See the gedit manual for more information.

  6. If you use applications that use panes, such as the file manager and Help browser, you may need to change the size of panes to accommodate the large print. See the online help for the appropriate application for more information.


Chapter 5. Mobility Impairments

Mobility impairments can be caused by arthritis, stroke, cerebral palsy, Parkinson's disease, multiple sclerosis, and loss of limbs or digits, among others. Poor muscle control or weakness can make using standard keyboards and mouse devices difficult. For instance, some people are unable to type two keys simultaneously, while others tend to hit multiple keys or to bounce keys when pressing or releasing them. People who are able to use only one hand likewise have difficulties with some keyboard and mouse tasks.

The technologies which can assist those with mobility impairments are:

  • On-Screen Keyboard - lets users select keys using a pointing method such as pointing devices, switches, or Morse-code input systems.

  • Mouse and Keyboard Enhancements - helpful for users who have trouble typing and controlling a mouse or a keyboard.


5.1. On-Screen Keyboard

The On-Screen Keyboard application displays virtual keyboards on your desktop. You can use the standard mouse pointer or alternative pointing device to operate the virtual keyboards. On-Screen Keyboard displays the following types of keyboards:

  • Composer Keyboards enable you to compose text. To type alphanumeric characters, you select the characters on the composer keyboard.

  • Dynamic Keyboards reflect the applications that are currently running on the desktop. For example, On-Screen Keyboard generates dynamic keyboards that contain keys to represent the applications that are running on your desktop or the menus that are contained in an application.

To start On-Screen Keyboard, choose Applications->Accessibility->On-Screen Keyboard. For more information about the On-Screen Keyboard application, see the Help for On-Screen Keyboard.


5.1.1. Maximizing Application Windows for On-Screen Keyboard Users

If you are an On-Screen Keyboard user, you cannot use any application in Full-Screen mode because the application window obscures the On-Screen Keyboard display.

To resize the window for use with the On-Screen Keyboard application, perform the following steps:

  1. Do not enable the Full-Screen mode in the application.

  2. Give focus to the application window.

  3. Press F10 to maximize the application.


5.2. Mouse and Keyboard Enhancements

This section describes how to configure the mouse and keyboard to make these devices accessible to more users.


5.2.1. Configuring the Mouse

Use the Mouse preference tool to configure the mouse to suit your needs. To open the Mouse preference tool, choose System->Preferences->Mouse . The Mouse Preferences dialog is displayed.


5.2.1.1. Configuring Mouse Behavior

The following sections describe how to modify the behavior of the mouse to suit your needs.


5.2.1.1.1. Configuring the Mouse for Left-Handed Use

To configure the mouse for left-handed use, click on the Buttons tab in the Mouse Preferences dialog, then select the Left-handed mouse option. When you select this option, the system swaps the functions of the left mouse button and the right mouse button immediately.


5.2.1.1.2. Configuring Double-Click Behavior

If you have difficulty double-clicking, you can increase the period of time that the system allows to elapse between the first click and the second click of a double-click. For example, if the double-click timeout setting is 0.4 seconds, you must perform the second click of a double-click within 0.4 seconds of the first click. If the second click occurs more than 0.4 seconds after the first click, the system interprets the two clicks as two single clicks.

To configure the double-click timeout setting, perform the following steps:

  1. Click on the Buttons tab in the Mouse Preferences dialog.

  2. Use the Timeout slider to specify the timeout in seconds that the system allows between the two clicks of a double-click. Moving the slider to the right will increase the timeout interval in 0.1 second intervals. In the same manner, moving the slider to the left will decrease the timeout in 0.1 second intervals.

  3. Double-click on the light bulb to the right of the slider to test the setting. If you perform the two clicks of the double-click within the timeout specified, the light bulb lights up fully to display a yellow glow around the bulb. If you do not double-click within the timeout specified, the light bulb does not light fully. You should increase the timeout setting and try again. When the light bulb lights, the timeout setting is suitable for your needs.


5.2.1.1.3. Changing Mouse Pointer Size

To change the size of the mouse pointer that is displayed on the desktop, perform the following steps:

  1. Click on the Pointers tab in the Mouse Preferences dialog.

  2. This will display a list of pointer themes and sizes available.

  3. By default, GNOME does not include mouse pointer themes. Information about installing and using pointer themes can be found in the User Guide.

Note

On some platforms you must log out and log in again for this setting to take effect.


5.2.1.1.4. Locating the Mouse Pointer

If you have difficulty locating the mouse pointer on the screen, you can enable an option to highlight the pointer when you press the Control key. To enable this option, click on the Pointers tab in the Mouse Preferences dialog, then select the Highlight the pointer when you press Ctrl option. When you press Control, the system displays an animation around the pointer to highlight the pointer.

Note

On some platforms, you must log out and log in again before this setting takes effect.


5.2.1.1.5. Configuring Mouse Speed and Sensitivity

To configure the speed and sensitivity of the mouse, perform the following steps:

  1. Click on the Motion tab in the Mouse Preferences dialog.

  2. Configure the following options:

    Acceleration

    Use the slider to specify the speed at which the mouse pointer moves around the screen when you move the mouse.

    If you select a low setting, the mouse pointer moves at a speed similar to the speed at which you are physically moving the mouse. This means that you need to physically move the mouse larger distances to cover the screen area. If you select a high setting, the mouse pointer moves at a faster speed than the speed at which you physically move the mouse. This means that you need to physically move the mouse small distances to cover the screen area.

    Sensitivity

    Use the slider to specify how responsive the mouse pointer is to movements of the mouse. Moving the slider to the right will increase the sensitivity and moving it to the left will decrease the sensitivity.

    Threshold

    Use the slider to specify the distance that you must move an item before the system interprets the move action as a drag-and-drop action.


5.2.1.2. Configuring the Cursor

The following section describes how to modify the display characteristics of the cursor.


5.2.1.2.1. Stopping the Cursor from Blinking

To stop the cursor from blinking in text boxes and other areas, perform the following steps:

  1. Choose System->Preferences->Keyboard to start the Keyboard preference tool.

  2. In the Keyboard tabbed section, deselect the Cursor blinks in text boxes and fields option.


5.2.1.3. Keyboard Mouse Emulation

If you have difficulty using a mouse, you can use the keyboard to emulate the mouse functions. See Section 5.2.2.2 of this guide for more information.


5.2.2. Configuring the Keyboard

Use the Keyboard preference tool to configure the keyboard accessibility options. To open the Keyboard preference tool, choose System ->Preferences->Keyboard. Accessibility options can be enabled by selecting Accessibility. This will open a new dialog, Keyboard Accessibility Preferences, also known as AccessX.

The Keyboard Accessibility Preferences (AccessX) dialog enables you to customize your keyboard in the following ways:

  • Using the numeric keypad to emulate mouse actions. See Section 5.2.2.2.

  • Specifying the duration for which you must press and hold a key before the system accepts the keypress. See Section 5.2.2.3.

  • Ignoring rapid, repeated keypresses of the same key. See Section 5.2.2.4.

  • Accepting key combinations in sequence rather than simultaneously. See Section 5.2.2.5.

  • Emitting an audible notification when a user activates or deactivates a toggle key. See Section 5.2.2.6.

  • Ignoring long keypresses of the same key and control the repeat rate of a keypress. See Section 5.2.2.7.


5.2.2.1. Activating Keyboard Accessibility Options

To activate the keyboard accessibility options, perform the following steps:

  1. Choose System->Preferences->Keyboard and select Accessibility

  2. Select the Enable keyboard accessibility features option.

  3. Click on the Basic tab.

  4. Select the Beep when features turned on or off from keyboard option to receive an audible notification each time a keyboard accessibility option changes; to toggle these settings, use the following keyboard shortcuts:

    • Press and hold Shift for eight seconds to enable or disable the Slow Keys feature.

    • Press Shift five times to enable or disable the Sticky Keys feature.

  5. To automatically disable the keyboard accessibility options if the options are not used for a specified number of seconds, select the Disable if unused for X seconds option. Use the slider to specify the number of seconds of keyboard idle time required before the system disables the keyboard accessibility options.

    This option is intended for computers that are shared by a number of different users, some of whom require the keyboard accessibility options.

  6. Changes made will be instantly applied.


5.2.2.2. Enabling Mouse Emulation

The mouse keys feature enables you to use the numeric keypad on the keyboard to emulate mouse actions. This feature benefits users who have difficulty using a mouse or other pointing device. To enable and configure the mouse keys feature, perform the following steps:

  1. In the Keyboard Accessibility Preferences (AccessX) dialog, select the Mouse Keys tab.

  2. Select the Enable Mouse Keys option.

  3. Configure the following options to determine the behavior of the mouse pointer when you control the pointer from the numeric keypad:

    Maximum Pointer Speed

    Use this spin box to specify the maximum speed in pixels per second at which the pointer moves around the screen.

    Elapsed Time before Maximum Mouse Speed

    Use this spin box to specify the duration in milliseconds before the pointer accelerates to the maximum pointer speed.

    Delay between Keypress and Pointer Movement

    Use this spin box to specify the interval in milliseconds between a keypress and the time when the pointer starts to move.

When you enable mouse keys, the keys on the numeric keypad have the following functions:

Table 5-1. Numeric Keypad to Mouse Function Mapping

Numeric Keypad Keys

Function

1, 2, 3, 4, 6, 7, 8, 9

Move the mouse pointer around the screen

5

Mouse button click

0

Mouse button toggle

/

Primary mouse button

*

Secondary mouse button

-

Tertiary mouse button

The Toggle Mouse Button key enables the currently selected mouse button until the Mouse button click key is pressed. This allows you to perform drag and drop operations.

The Mouse button click emulates the currently selected mouse button. Pressing /, * or - will change the behaviour of this. The currently selected mouse button can be seen in the Keyboard Accessibility Status panel application, discussed in Section 5.2.3.

Note

The Primary mouse button is the left mouse button for right-handed people. The Secondary mouse button is the right mouse button and the Tertiary mouse button is the middle mouse button.

Some Solaris systems also use the function keys to emulate the mouse buttons. The function-key-to-mouse-button mappings are described in the following table:

Table 5-2. F-Key to Mouse Action Mapping on Solaris Systems

Function Key

Function

F2

Mouse button 1

F3

Mouse button 2

F4

Mouse button 3


5.2.2.3. Enabling Slow Keys

The slow keys feature enables you to customize how the keyboard handles user input in the following ways:

  • Specify the duration for which you must press and hold a key before the system accepts the keypress. This aspect of the feature benefits users who frequently press keys that they do not intend to press.

  • Enable audible indications of keyboard input and acceptance. This aspect of the feature benefits users who cannot see the result of a keypress.

To enable and configure the slow keys feature, perform the following steps:

  1. From the Keyboard Accessibility Preferences (AccessX) dialog, select the Filters tab.

  2. Select the Enable Slow Keys option.

    Tip

    To select or deselect the Slow Keys feature from the keyboard, press and hold Shift for eight seconds. This will present a dialog confirming that you want Slow Keys enabled. The Shift keyboard shortcut automatically selects all of the Slow Keys options. If you selected the Beep when features turned on or off from the keyboard option in the Basic tab, after four seconds the system beeps three times to indicate that the system is about to select or deselect the feature.

  3. Use the Only accept keys held for slider or spin box to specify the duration, in milliseconds, for which you must press and hold a key before the system accepts the keypress. Use the Type to test settings text box to test the Slow Keys setting and modify the setting as required.

  4. To enable audible indications of keyboard input and acceptance, select the following options:

    Beep when key is pressed

    Select this option to hear a beep when you press a key.

    Beep when key is accepted

    Select this option to hear a beep when the system accepts a keypress.

    Beep when key is rejected

    Select this option to hear a beep when the system rejects a keypress. The system rejects a keypress if you do not press and hold the key for the duration that is specified in the Only accept keys held for spin box.


5.2.2.4. Enabling Bounce Keys

The bounce keys feature enables you to customize the keyboard to ignore rapid, repeated keypresses of the same key. For example, users with impaired motor skills might press the same key several times when they intend to press the key once. This feature enables you to customize the keyboard to ignore repeated keypresses.

To enable and configure the Bounce Keys feature, perform the following steps:

  1. From the Keyboard Accessibility Preferences (AccessX) dialog, select the Filters tab.

  2. Select the Enable Bounce Keys option.

  3. Use the Ignore duplicate keypresses within slider or spin box to specify the duration in milliseconds (ms) after the first keypress for which the system ignores repeated keypresses of the same key. For example, if you select a duration of 500 ms, the system ignores all repeated keypresses of the same key that occur within half a second of the first keypress.

  4. Select the Beep if key is rejected option to hear an audible indication when the system ignores a key.

Note

If you want to enable the Bounce Keys feature, ensure that the Enable Slow Keys option is deselected. The Slow Keys feature requires you to press a key for a specified duration before the system accepts the keypress as a valid keypress. If you cannot press the key for the duration that is specified by the Slow Keys setting, deselect the Enable Slow Keys option to enable the system to accept your input.


5.2.2.5. Enabling Sticky Keys

The sticky keys feature enables you to press key combinations in sequence rather than simultaneously. This feature is designed for users who are unable to press two or more keys at the same time.

To enable and configure the Sticky Keys feature, perform the following steps:

  1. From the Keyboard Accessibility Preferences (AccessX) select the Basic tab.

  2. Select the Enable Sticky Keys option.

    Tip

    To enable the Sticky Keys feature from the keyboard, press Shift five times. This will present a dialog confirming that you with to enable Sticky Keys. The Shift keyboard shortcut automatically selects all of the Sticky Keys options. If you selected the Beep when features turned on or off from the keyboard option, the system beeps to indicate that the system is about to select or deselect the feature. When active, pressing Shift five times in a row will present a dialog asking if you want to disable Sticky Keys.

  3. Select the Beep when modifier is pressed option to receive an audible indication each time you press a modifier key such as Ctrl, Alt, or Shift. This option is useful to remind you whether a modifier key is active or inactive.

  4. Selecting the Disable if two keys pressed together option will present a dialog with the option to disable Sticky Keys if two keys are pressed at the same time.

You can use the Sticky Keys feature in Latch or Lock mode. The following table describes how to choose a mode and the difference between the two modes:

Table 5-3. Sticky Keys Latch or Lock Mode

To use the Sticky Keys feature in...

Press the modifier key...

The modifier key remains active until...

Latch mode

Once.

You press a non-modifier key.

Lock mode

Twice in quick succession.

You press the modifier key again.

Example 1: If you want to press Alt-F1, do the following:

  1. Press Alt to latch the modifier key. The Alt key remains active.

  2. Press F1. The key combination is now complete. After you press F1, the Alt modifier key is no longer active.

Example 2: If you want to press Ctrl-Alt-Tab, do the following:

  1. Press Ctrl twice to lock the modifier key. The Ctrl key remains active.

  2. Press Alt.

  3. Press Tab. The key combination is now complete.

  4. To unlock the modifier key, press Ctrl again.


5.2.2.6. Enabling Audible Toggle Key Notifications

A toggle key is any key on the keyboard that can switch between two states. The Num Lock, Caps Lock, and Scroll Lock keys are toggle keys. Most toggle keys have an associated light emitting diode (LED) on the keyboard that lights when the toggle key is active. To assist users with visual impairments, you can customize the keyboard to emit an audible notification when a user presses a toggle key. For example, when you press Num Lock, you can determine whether the key is toggled or not by the sound emitted.

To enable accessible toggle keys, perform the following steps:

  1. From the Keyboard Accessibility Preferences (AccesX) select the Filters tab.

  2. Select the Enable Toggle Keys option.

When you activate the Num Lock, Caps Lock, or Scroll Lock keys, the system beeps once. When you deactivate a toggle key, the system beeps twice.


5.2.2.7. Enabling Repeat Keys

The Repeat Keys feature enables you to repeat a keystroke multiple times without pressing the key more than once. This feature is designed for users who cannot release keys quickly; for example, users who operate a mouth stick. When you enable repeat keys, you can specify the duration for which you must press a key before the key starts to repeat.

To enable and configure the Repeat Keys feature, perform the following steps:

  1. From the Keyboard Accessibility Preferences (AccessX) select the Basic tab.

  2. Select the Enable Repeat Keys option.

  3. Use the Delay slider or spin box to specify the duration for which you must press a key before the keyboard interprets the action as a repeat key. If you have difficulty releasing keys, select a long time delay.

  4. Use the Speed slider or spin box to specify the speed at which the keyboard repeats the keypress as input.


5.2.3. Using the Keyboard Accessibility Status Panel Application

The Keyboard Accessibility Status panel application shows you the status of the keyboard accessibility features. This panel application displays icons to indicate which keyboard accessibility features are enabled in the Keyboard Accessibility preference tool.

To add the Keyboard Accessibility Status panel application to a panel, right-click on the panel, then choose Add to Panel and select Keyboard Accessibility Status.

The following table describes the icons that the panel application displays and the status that each icon represents:

Table 5-4. Keyboard Accessibility Status Icons

Icon

Keyboard Accessibility Status

Keyboard accessibility is available but none of the individual features are enabled.

The Bounce Keys feature is enabled.

The Mouse Keys feature is enabled. The dot in the mouse button shows which button is currently associated with the Mouse button click key.

The Slow Keys feature is enabled.

The Sticky Keys feature is enabled and the Alt key is latched.

The Sticky Keys feature is enabled and the Alt key is locked.

The Sticky Keys feature is enabled and the Ctrl key is latched.

The Sticky Keys feature is enabled and the Ctrl key is locked.

The Sticky Keys feature is enabled and the Shift key is latched.

The Sticky Keys feature is enabled and the Shift key is locked.

The Sticky Keys feature is enabled and the Super/Windows key is latched.

The Sticky Keys feature is enabled and the Super/Windows key is locked.



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