Engineering Accessibility: Practical, Maintainable, Testable (Do iOS 2025)

Accessibility fixes are easy; Making them fit cleanly into a real codebase is the hard part. This talk shows you how to meet accessibility requirements with tools, automation, and solid engineering practices that keep your code clean and maintainable.

Talk given at Do iOS 2025

Transcript

1. engineering accessibility practical, maintainable, testable
3. gas factory
4. gas factory une usine à gaz
5. practical maintainable testable
6. where do i start?
7. this is terrible advice
8. .accessibilityLabel("play") .accessibilityLabel("pause") .accessibilityLabel("shuffle")
9. systems engineer
10. compositionality
11. compositionality if the pieces are accessible, the app is accessible
12. start by making the pieces accessible
13. use system components
14. don't reinvent the wheel
15. custom styles // declare style struct FunStyle: ToggleStyle { func makeBody(configuration: Configuration) -> some View { ... } } // usage Toggle("Fun Style", isOn: $isOn) .toggleStyle(FunStyle())
16. style the wheel
18. make good accessible choices
19. make good accessible choices color touch target large font etc.
20. zoom out
22. maintainable
23. maintainable good names documentation comments PR checklist
24. stubborn lazy
25. stubborn lazy efficient
26. make it hard NOT to be accessible
27. strict APIs strict warnings tests
28. strict APIs
29. struct ParentView: View { var body: some View { MyToggleView(accessibilityLabel: "my accessibility label") } }
30. struct ParentView: View { var body: some View { MyToggleView(accessibilityLabel: "my accessibility label") } } struct MyToggleView: View { var accessibilityLabel: String var body: some View { Toggle("", isOn: $isOn) .toggleStyle(PillToggleStyle()) .accessibilityLabel(accessibilityLabel) } }
31. warnings
32. custom_rules: a11y_label: included: - ".*\\_molecule.swift" excluded: - ".*\\_atom.swift" name: "Accessibility Label" regex: "" message: "Set label at atom level, not molecule" severity: error
33. unit tests
34. unit tests @Test func testDecorativeImageIsHidden() throws { let view = Image(systemName: "star.fill") .accessibilityHidden(true) let image = try view.inspect().image() let isHidden = try image.accessibilityHidden() #expect(isHidden == true) } https://github.com/nalexn/ViewInspector
35. unit tests .accessibilityLabel("") .accessibilityHint("") .accessibilityHidden(true) https://github.com/nalexn/ViewInspector
36. unit tests ViewInspector basic mapping (hint, hidden) isolated UI component
37. snapshot tests https://github.com/cashapp/AccessibilitySnapshot
38. https://github.com/cashapp/AccessibilitySnapshot
39. snapshot tests https://github.com/cashapp/AccessibilitySnapshot https://github.com/pointfreeco/swift-snapshot-testing
40. AccessibilitySnapshot labels order
41. Swift Snapshot Testing large font light/dark mode
42. UI tests
43. UI tests main flow in landscape XCUIDevice.shared.orientation = .landscapeLeft
44. UI tests main flow in largest font app.launchArguments += [ "-UIPreferredContentSizeCategoryName", "UICTContentSizeCategoryAccessibilityXXXL" ]
45. performAccessibilityAudit(for:_:)
46. performAccessibilityAudit(for:_:)
47. override func setUpWithError() throws { continueAfterFailure = true } func testPerformAudit() throws { let app = XCUIApplication() app.launch() try app.performAccessibilityAudit() }
48. override func setUpWithError() throws { continueAfterFailure = true } func testPerformAudit() throws { let app = XCUIApplication() app.launch() try app.performAccessibilityAudit(for: .contrast) }
49. performAccessibilityAudit(for:_:) isolated tests (1 criteria, 1 screen)
50. stubborn lazy
51. stubborn lazy bad at French
52. https://github.com/djavan-bertrand/AutoScreenshotGenerationDemo
53. func testTakeScreenshots() throws { takeScreenshot() }
54. visuals all configurations all devices languages orientation (portrait/landscape) large/small font sizes high contrast reduced transparency etc.
55. zoom out
56. manual testing
57. usable and understandable by everyone no matter their abilities or disabilities
59. gas factory
60. compositionality
61. system components
62. maintainable
63. make it hard NOT to be accessible
64. strict APIs warnings tests
65. visual
66. zoom out
67. thank y'all! i'm on a mission to make accessible mobile apps the default, not the exception