Implementing iOS accessibility features

On iOS certain accessibility features requires us to define functions to the Native-objects.

Functions:

accessibilityActivate()

Tells the element to activate itself and report the success or failure of the operation.

accessibilityIncrement()

Tells the accessibility element to increment the value of its content.

User action: A one-finger swipe up that increments a value in an element.

accessibilityDecrement()

Tells the accessibility element to decrement the value of its content.

User action: A one-finger swipe down that decrements a value in an element.

accessibilityScroll(UIAccessibilityScrollDirection)

Scrolls screen content in an application-specific way and returns the success or failure of the action.

User action: A three-finger swipe that scrolls content vertically or horizontally.

accessibilityPerformEscape()

Dismisses a modal view and returns the success or failure of the action.

User action: A two-finger Z-shaped gesture that dismisses a modal dialog, or goes back one level in a navigation hierarchy. Returns true, if we're handling the escape. Dev note: Unlike accessibilityPerformMagicTap() this cannot be added to the AppDelegate in NativeScript.

accessibilityPerformMagicTap()

Performs a salient action.

User action: A two-finger double-tap that performs the most-intended action. This could be play/pause in an audio-player or pick/hang up in a phone-app. Dev note: Can be added to the AppDelegate in NativeScript.

Links

https://developer.apple.com/documentation/uikit/accessibility/uiaccessibilityaction https://developer.apple.com/library/content/featuredarticles/ViewControllerPGforiPhoneOS/SupportingAccessibility.html