| ## 3.10\. Accessibility |
| |
| Android provides an accessibility layer that helps users with disabilities to |
| navigate their devices more easily. In addition, Android provides platform APIs |
| that enable accessibility service implementations to receive callbacks for user |
| and system events and generate alternate feedback mechanisms, such as |
| text-to-speech, haptic feedback, and trackball/d-pad navigation. |
| |
| If device implementations support third-party accessibility services, they: |
| |
| * [C-1-1] MUST provide an implementation of the Android accessibility |
| framework as described in the [accessibility APIs]( |
| http://developer.android.com/reference/android/view/accessibility/package-summary.html) |
| SDK documentation. |
| * [C-1-2] MUST generate accessibility events and deliver the appropriate |
| `AccessibilityEvent` to all registered [`AccessibilityService`]( |
| http://developer.android.com/reference/android/accessibilityservice/AccessibilityService.html) |
| implementations as documented in the SDK. |
| * [C-1-4] MUST add a button in the system's navigation bar allowing the user |
| to control the accessibility service when the enabled accessibility services |
| declare the [`AccessibilityServiceInfo.FLAG_REQUEST_ACCESSIBILITY_BUTTON`]( |
| https://developer.android.com/reference/android/accessibilityservice/AccessibilityServiceInfo.html#FLAG%5FREQUEST%5FACCESSIBILITY%5FBUTTON) |
| . Note that for device implementations with no system navigation bar, this |
| requirement is not applicable, but device implementations SHOULD provide a |
| user affordance to control these accessibility services. |
| |
| |
| If device implementations include preinstalled accessibility services, they: |
| |
| * [C-2-1] MUST implement these preinstalled accessibility services as [Direct Boot Aware]( |
| https://developer.android.com/reference/android/content/pm/ComponentInfo.html#directBootAware) |
| apps when the data storage is encrypted with File Based Encryption (FBE). |
| * SHOULD provide a mechanism in the out-of-box setup flow for users to enable |
| relevant accessibility services, as well as options to adjust the font size, |
| display size and magnification gestures. |
