61 lines
1.5 KiB
Swift
61 lines
1.5 KiB
Swift
//
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// ContrastDisplayContext.swift
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// DynamicColorExample
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//
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// Created by Yannick LORIOT on 26/11/2016.
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// Copyright © 2016 Yannick LORIOT. All rights reserved.
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//
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import Foundation
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#if os(iOS) || os(tvOS) || os(watchOS)
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import UIKit
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#elseif os(OSX)
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import AppKit
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#endif
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extension DynamicColor {
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/**
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Used to describe the context of display of 2 colors.
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Based on WCAG: https://www.w3.org/TR/2008/REC-WCAG20-20081211/#visual-audio-contrast-contrast
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*/
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public enum ContrastDisplayContext {
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/**
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A standard text in a normal context.
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*/
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case standard
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/**
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A large text in a normal context.
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You can look here for the definition of "large text":
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https://www.w3.org/TR/2008/REC-WCAG20-20081211/#larger-scaledef
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*/
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case standardLargeText
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/**
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A standard text in an enhanced context.
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Enhanced means that you want to be accessible (and AAA compliant in WCAG)
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*/
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case enhanced
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/**
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A large text in an enhanced context.
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Enhanced means that you want to be accessible (and AAA compliant in WCAG)
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You can look here for the definition of "large text":
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https://www.w3.org/TR/2008/REC-WCAG20-20081211/#larger-scaledef
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*/
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case enhancedLargeText
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var minimumContrastRatio: CGFloat {
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switch self {
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case .standard:
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return 4.5
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case .standardLargeText:
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return 3
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case .enhanced:
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return 7
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case .enhancedLargeText:
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return 4.5
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}
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}
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}
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}
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