24.3 · Right-to-left layout, bidirectional text and number systems

Hundreds of millions of people read right to left. A layout that hard-codes “left” and “right” is wrong for all of them, and the fix is mostly using the right words from the start.

Mental model. Think in start and end, not left and right. Mirror what is directional, and leave what is not (clocks, media controls, numbers, logos).

Mirroring

Leading and trailing, semantic attributes, images, and what not to flip.

1. How do you support right-to-left languages: leading and trailing, semantic content attributes, flipping images, and testing? 24.3.1 · L3
   In a right-to-left (RTL) language such as Arabic or Hebrew the whole interface mirrors: the back button, the navigation flow, the order of tabs and the…

Text and numbers

Bidirectional text, isolating user content, and non-Latin digits.

1. How is bidirectional text handled, why should you isolate user-generated strings, and how do different locales write numbers? 24.3.2 · L3
   Real text mixes directions: an Arabic or Hebrew sentence containing an English brand name, a number or a URL. The Unicode bidirectional algorithm decides how…

More in Accessibility & localization

• 24.1 · VoiceOver, accessibility elements and the other ways people use an app
• 24.2 · Dynamic Type, display settings, contrast and touch targets
• 24.4 · Testing localisation, and sorting, calendars and names by locale
• 24.5 · Auditing and testing accessibility, and making it a bar, not a backlog
• 24.6 · Building and testing accessible components
• 24.7 · Adaptive colour, font fallback and mirrored drawing
• 24.8 · Language matching, plural rules, string catalogs and Info.plist strings
• 24.9 · Unicode equivalence, word boundaries and regional defaults