Android Talkback

iOS

Developer notes

• A non-interactive animation is a technique by which still images are manipulated to create moving images
• Animations can affect users with motion disabilities. Guidance is to keep animations to 5 seconds or less
• Animations that flash can also have a deadly affect to users with epilepsy. Guidance is to keep flashing to no more than 3 times per second
• Ensure animations that are meaningful have alt text assigned
• Animations cannot stop and start again unless screen is refreshed or similar
• If a stop/pause button next to the animation is provided, the animation can run more than 5 seconds
• Loading icon animation is exempt from the 5 second guidance

Name

• Programmatic name describes the meaning of the animation.

• If visible text label exists, the programmatic name should match the visible text label.

• UIKit
  • You can programmatically set the visible label with setTitle().
    • The _component title will overwrite the _component accessibilityLabel.
  • If a visible label is not applicable in this case, set the _component accessibilityLabel to the label of your choice.
    • To do this in Interface Builder, set the label using the Identity Inspector
  • To hide labels from VoiceOver programmatically, set the label’s isAccessibilityElement property to false
  • To hide labels from VoiceOver using Interface Builder, uncheck Accessibility Enabled in the Identity Inspector.
• SwiftUI
  • If no visible label, use view modifier accessibilityLabel(_:).

Focus

• Use the device’s default focus functionality.
• Consider how focus should be managed between child elements and their parent views.

• Initial focus on a screen should land in a logical place, such as back button, screen title, first text field, or first heading.

• UIKit
  • If VoiceOver is not reaching a particular element, set the element’s isAccessibilityElement to true
    • Note: You may need to adjust the programmatic name, role, state, and/or value after doing this, as this action may overwrite previously configured accessibility.
  • Use accessibilityViewIsModal to contain the screen reader focus inside the modal.
  • To move screen reader focus to newly revealed content, use UIAccessibility.post(notification:argument:) that takes in .screenChanged and the newly revealed content as the parameter arguments.
  • To NOT move focus, but dynamically announce new content: use UIAccessibility.post(notification:argument:) that takes in .announcement and the announcement text as the parameter arguments.
  • UIAccessibilityContainer protocol: Have a table of elements that defines the reading order of the elements.
• SwiftUI
  • For general focus management that impacts both screen readers and non-screen readers, use the property wrapper @FocusState to assign an identity of a focus state.
    • Use the property wrapper @FocusState in conjunction with the view modifier focused(_:) to assign focus on a view with @FocusState as the source of truth.
    • Use the property wrapper @FocusStatein conjunction with the view modifier focused(_:equals:) to assign focus on a view, when the view is equal to a specific value.
  • If necessary, use property wrapper @AccessibilityFocusState to assign identifiers to specific views to manually shift focus from one view to another as the user interacts with the screen with VoiceOver on.

Android

Developer notes

• A non-interactive animation is a technique by which still images are manipulated to create moving images
• Animations can affect users with motion disabilities. Guidance is to keep animations to 5 seconds or less
• Animations that flash can also have a deadly affect to users with epilepsy. Guidance is to keep flashing to no more than 3 times per second
• Ensure animations that are meaningful have alt text assigned
• Animations cannot stop and start again unless screen is refreshed or similar
• If a stop/pause button next to the animation is provided, the animation can run more than 5 seconds
• Loading icon animation is exempt from the 5 second guidance

Name

• Name describes the meaning of the animation

• Android Views
  • android:text XML attribute
  • Optional: use contentDescription for a more descriptive name, depending on type of view and for elements (icons) without a visible label
  • contentDescription overrides android:text
  • Use labelFor attribute to associate the visible label with the element
• Jetpack Compose
  • Compose uses semantics properties to pass information to accessibility services.
  • Example specification of contentDescription in compose: modifier = Modifier.semantics { contentDescription = "" }

Focus

• Only manage focus when needed. Primarily, let the device manage default focus
• Consider how focus should be managed between child elements and their parent views

• Initial focus on a screen should land in a logical place (back button, screen title, first text field, first heading)

• Android Views
  • importantForAccessibility makes the element visible to the Accessibility API
  • android:focusable
  • android=clickable
  • Implement an onClick( ) event handler for keyboard, as well as onTouch( )
  • nextFocusDown
  • nextFocusUp
  • nextFocusRight
  • nextFocusLeft
  • accessibilityTraversalBefore (or after)
  • To move screen reader focus to newly revealed content: Type_View_Focused
  • To NOT move focus, but dynamically announce new content: accessibilityLiveRegion(set to polite or assertive)
  • To hide controls: importantForAccessibility=false
  • For a ViewGroup, set screenReaderFocusable=true and each inner object’s attribute to keyboard focus (focusable=false)
• Jetpack Compose
  • Modifier.focusTarget() makes the component focusable
  • Modifier.focusOrder() needs to be used in combination with FocusRequesters to define focus order
  • Modifier.onFocusEvent(), Modifier.onFocusChanged() can be used to observe the changes to focus state
  • FocusRequester allows to request focus to individual elements with in a group of merged descendant views
  • Example: To customize the focus events
    • step 1: define the focus requester prior. val (first, second) = FocusRequester.createRefs()
    • step 2: update the modifier to set the order. modifier = Modifier.focusOrder(first) { this.down = second }
    • focus order accepts following values: up, down, left, right, previous, next, start, end
    • step 3: use second.requestFocus() to gain focus