Accessibility

Accessibility

Introduction
This module is designed to help users who have difficulty hearing audible cues, or who have difficulty using a keyboard.
The module is divided into five tabs: Bell, Modifier keys, Keyboard Filters, Activation Gestures and Screen Reader.

Bell
This panel is divided into an Audible Bell section and a Visible Bell section.
The top check box labeled Use System Bell, determines whether the normal System bell rings. If this option is disabled, the System bell will be silenced.
The next check box down can be used to play a different sound whenever the system bell is triggered. To activate, place a mark in the check box labeled Use customized bell, and enter the complete pathname to the sound file in the text box labeled Sound to play. If you want, you can select the Browse button to navigate through your filesystem to find the exact file.
For those users who have difficulty hearing the System bell, or those users who have a silent computer, offers the visual bell. This provides a visual signal (inverting the screen or flashing a color across it) when the system bell would normally sound.
To use the visual bell, first place a mark in the check box labeled Use visual bell.
You can then select between Invert screen, or Flash screen. If you select Invert screen, all colors on the screen will be reversed. If you choose Flash screen, you can choose the color by clicking the button to the right of the Flash screen selection.
The spin box can be used to adjust the duration of the visible bell. The default value is 500 msec, or half a second.

Modifier keys
There are the two sections Sticky Keys and Locking Keys to this panel.
Use Sticky Keys 	 If this option is enabled, you can press and release the , or keys, and then press another key to get a key combo (example: Del could be done with then then Del).
Also in this section is a check box labeled Lock Sticky Keys. If this check box is enabled, the , and keys stay selected until you de-selected them.
As an example:
With Lock Sticky Keys disabled: 	 If you press the key then press the F key, the computer interprets this as F. Now if you type a P, the computer interprets this as the letter p (no shift).
With Lock Sticky Keys enabled: 	 If you press the key twice then press the F key, the computer interprets this as F. Now if you type a P, the computer interprets this as the letter P (P). To de-select the key, press it again.

Keyboard Filters
There are two sections to this panel.
Use slow keys 	 If this option is enabled, you must hold the key down for a specified length of time (adjustable with the spin box) before the keystroke will be accepted. This helps prevent accidental key strokes.
Use bounce keys 	 If this option is enabled, you must wait for a specified length of time (configurable with the spin box) before the next key press can be accepted. This prevents accidental multiple key strokes.

Activation Gestures
There are two sections to this panel.
Activation Gestures with these options: 	
Use gestures for activating sticky keys and slow keys
Here you can activate keyboard gestures that turn on the following features:
Mouse Keys: Press +NumLock
Sticky keys: Press key 5 consecutive times
Slow keys: Hold down for 8 seconds
Turn sticky keys and slow keys off after a certain period of inactivity
Notification with these options: 	
Use the system bell whenever a gesture is used to turn an accessibility feature on or off
Show a confirmation dialog whenever a keyboard accessibility feature is turned on or off
If this option is checked, will show a confirmation dialog whenever a keyboard accessibility feature is turned on or off.
Ensure you know what you are doing if you uncheck it, as the keyboard accessibility settings will then always be applied without confirmation.
Use 's system notification mechanism whenever a keyboard accessibility feature is turned on or off
Click the Configure Notifications button to open a dialog which allows you to edit the notifications for status changes of all keys.

Screen Reader
Install a screen reader application like Orca together with speech-dispatcher.
Test that sound from speech dispatcher works using the command spd-say hello in a terminal.
In addition you need a text to speech synthesizer like ⪚ espeak.
Enable the screen reader in the checkbox, logout and restart your desktop session.
For itself, make sure to use the traditional Application Menu, and check that this menu has a keyboard shortcut associated (F1). When pressing this shortcut, the menu should open and be read when navigating the menu with the arrow keys.