Day 210

14 Dec 2022

iOS and Xcode provide a wide variety of tools and options to deal with color contrast ratios. From system colors, that automatically support Increase Contrast, to high contrast color and asset variants, and even a built-in contrast calculator.

Calendar of Advent of iOS Accessibility. Day 14. Color contrast. Some of the tools available in Xcode that help you create apps with great contrast are the asset catalog which lets you provide high contrast variants for color sets and assets, and the color contrast calculator. Some examples show how text size also affects contrast ratios. White on Black passes for all sizes. A grey with a 4.5 to 1 ratio over black will fail on small text sizes. A grey with a 2.9 to 1 ratio over black, fails for all text sizes. You can also use system colors an make sure that your app works well with the High Contrast setting.

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Day 153

Second day of @a11yTO! And again, lots of talks with a ton of practical information. So here's a thread with some of my highlights. And very proud that @spotifydesign was one of the sponsors! #a11yTOconf

Day 168

There is an Environment Overrides panel in the toolbar on top of Xcode's Debug Area. It allows you to select some of the most common accessibility options and Dynamic Type sizes, like in the Accessibility Inspector, plus select dark/light mode.

Accessibility Inspector Dynamic Type Xcode iOS

Day 192

If you don't use Color Sets in your Asset Catalog, and you define your color palette in code, you can still check if the user has Increase Contrast enabled to offer a slightly different color that improves the contrast ratio even more. Day 192 (2/2). You can check if the darker system colors is enabled: https://developer.apple.com/documentation/uikit/uiaccessibility/isdarkersystemcolorsenabled Listen to a notification in case this setting changes: https://developer.apple.com/documentation/uikit/uiaccessibility/darkersystemcolorsstatusdidchangenotification And also check if the accessibility contrast is high in your trait collection: https://developer.apple.com/documentation/uikit/uitraitcollection/accessibilitycontrast

Increase Contrast iOS

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