Perseus Dark Mode

THE DARKNESS YOU CAN FORCE

A3 Environment • CHANGELOG • MIT License

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Usages

1: Build Light/Dark/Auto option.
2: Be awared of Dark Mode changes.

Integration

Dependencies

Support Code

TheDarknessSupport.swift is a peace of code a widly helpful in accord with PDM.

PDM in Use

Approbation:

• Swift macOS app
• Swift iOS app

Business:

• Swift macOS app The Dark Moon
• Swift macOS app Convertor mov2gif

Contents

• In brief
• Requirements
• First-party software
• Third-party software
• Installation
  • Cocoa macOS project
  • UIKit iOS project
• Usage
  • Force Dark Mode
  • Get awared of DarkMode changes
  • DarkMode change sample
• Account points
• License
  • Other required licenses details
• Credits
• Contributing
• Author
  • Contact

Our Terms

Acronym	Stands for
CPL	Console_Perseus_Logger
PDM	Perseus_Dark_Mode
PGK	Perseus_Geo_Kit
A3	Apple_Apps_Approbation
T3	The_Technological_Tree
P2P	Person_to_Person

In brief

The great home-made product to accomplish Dark Mode switching task. PDM is a single author and personale solution developed in P2P relationship paradigm.

macOS app	iOS app	iOS Settings bundle

Important

The macOS App scenes taken from the motion picture The Hobbit based on the novel by J.R.R. Tolkien.
The iOS App scenes taken from the motion picture The Lord of The Rings based on the novel by J.R.R. Tolkien.

Requirements

To build:

• macOS Monterey 12.7.6+
• Xcode 14.2+

But as the single source code file TheDarknessStar.swift PDM can be used even in Xcode 10.1.

First-party software

MIT

Type	Name
Star	ConsolePerseusLogger / 1.7.1

Third-party software

MIT

Type	Name
Style	SwiftLint / v0.57.0 for Monterey+
Script	SwiftLint Shell Script to run SwiftLint
Action	cirruslabs/swiftlint-action@v1

Unlicense

Type	Name
Action	mxcl/xcodebuild@v3

Installation

Step 1: Import the Darkness either with SPM or standalone

Standalone: the single source code file TheDarknessStar.swift

Swift Package Manager: https://github.com/perseusrealdeal/PerseusDarkMode

Cocoa macOS project

Step 2: In the AppDelegate when applicationDidFinishLaunching call force

import Cocoa
import PerseusDarkMode

class AppDelegate: NSObject, NSApplicationDelegate {

    func applicationDidFinishLaunching(_ aNotification: Notification) {
        DarkModeAgent.force(DarkModeUserChoice)
    }
}

Step 3: Register the MainWindowController for Dark Mode changes

import Cocoa
import PerseusDarkMode

class MainWindowController: NSWindowController, NSWindowDelegate {

    override func windowDidLoad() {
        super.windowDidLoad()

        DarkModeAgent.register(stakeholder: self, selector: #selector(makeUp))
    }

    @objc private func makeUp() {
    
    // Runs every time if Dark Mode changes.
    // The current DarkMode value is reliable here.
    
    let isDark = DarkMode.style == .dark
    let _ = isDark ? "It's dark" : "No dark"
    
    }
}

UIKit iOS project

Step 2: In the AppDelegate when didFinishLaunchingWithOptions call force

import UIKit
import PerseusDarkMode

class AppDelegate: UIResponder { var window: UIWindow? }

extension AppDelegate: UIApplicationDelegate {

    func application(_ application: UIApplication, didFinishLaunchingWithOptions
        launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {

        // Register Settings Bundle
        registerSettingsBundle()

        // Init the app's window
        window = UIWindow(frame: UIScreen.main.bounds)

        // Give it a root view for the first screen
        window!.rootViewController = MainViewController.storyboardInstance()
        window!.makeKeyAndVisible()
        
        DarkModeAgent.force(DarkModeUserChoice)
        
        return true
    }
    
    func applicationDidBecomeActive(_ application: UIApplication) {

        // Actualize Dark Mode style to Settings Bundle
        if let choice = DarkModeAgent.isDarkModeSettingsKeyChanged() {
            DarkModeAgent.force(choice)
        }
    }
}

Step 3: Register the MainViewController and process traitCollectionDidChange for DarkMode changes

import UIKit
import PerseusDarkMode

class MainViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        DarkModeAgent.register(stakeholder: self, selector: #selector(makeUp))
    }

    override func traitCollectionDidChange(_ previousTraitCollection: UITraitCollection?) {
        super.traitCollectionDidChange(previousTraitCollection)

        if #available(iOS 13.0, *) {
            DarkModeAgent.processTraitCollectionDidChange(previousTraitCollection)
        }
    }
    
    @objc private func makeUp() {
    
    // Runs every time if Dark Mode changes.
    // The current DarkMode value is reliable here, DarkModeAgent selector registered.
    
    let isDark = DarkMode.style == .dark
    let _ = isDark ? "It's dark" : "No dark"
    
    }
}

Usage

Force Dark Mode

The Dark Mode of your app can be easely forced in .on, .off or .auto just call method force of DarkModeAgent like this.

DarkModeAgent.force(.off) // It's a sunny day for the app.

The force will change the appearance of your app immediately including system components and will make run all custom DarkMode code makeUp().

Get awared of DarkMode changes

To declare custom DarkMode sensitive code that runs every time if DarkMode Changes register the object or create a DarkMode trigger:

Use Case 1: Register an object to be notified on changes

class DarkModeSensitiveObject {

    init() {
        DarkModeAgent.register(stakeholder: self, selector: #selector(makeUp))
    }

    @objc private func makeUp() {
        // Runs evary time if Dark Mode changes.
    }
}

Use Case 2: Create a DarkMode trigger and give it an action

class DarkModeSensitiveObject {

    private var theDarknessTrigger = DarkModeObserver()

    init() {
        theDarnessTrigger.action = { _ in
            self.makeUp()
        }
    }

    private func makeUp() {
        // Runs evary time if Dark Mode changes.
    }
}

DarkMode change sample

Use Case: Custom DarkMode sensitive color

import PerseusDarkMode

#if canImport(UIKit)
import UIKit
#elseif canImport(Cocoa)
import Cocoa
#endif

#if os(iOS)
public typealias Color = UIColor
#elseif os(macOS)
public typealias Color = NSColor
#endif

public func rgba255(_ red: CGFloat,
                    _ green: CGFloat,
                    _ blue: CGFloat,
                    _ alpha: CGFloat = 1.0) -> Color {
    return Color(red: red/255, green: green/255, blue: blue/255, alpha: alpha)
}

extension Color {
    public static var customRed: Color {
        return DarkModeAgent.shared.style == .light ?
            rgba255(255, 59, 48) : rgba255(255, 69, 58)
    }
}

And use custom DarkMode sensitive color:

// Runs every time if the DarkMode changes. 
// Use KVO (DarkModeObserver) or be registered with DarkModeAgent. 
@objc private func makeUp() {
    self.backgroundColor = .customRed
}

`Account points

• Preconfigured Swift Package manifest Package.swift
• Preconfigured SwiftLint config .swiftlint.yml
• Preconfigured SwiftLint CI swiftlint.yml
• Preconfigured GitHub config .gitignore
• Preconfigured GitHub CI main.yml
• Changelog
• A3 environment specification
• SwiftLint shell script

License

MIT License, see LICENSE for details.

Copyright © 7530 - 7534 Mikhail A. Zhigulin of Novosibirsk
Copyright © 7533 - 7534 PerseusRealDeal

• The year starts from the creation of the world according to a Slavic calendar.
• September, the 1st of Slavic year. For instance, "Sep 01, 2025" is the beginning of 7534.

Other required licenses details

© 2025 The SwiftLint Contributors for SwiftLint
© GitHub for GitHub Action cirruslabs/swiftlint-action@v1
© 2021 Alexandre Colucci, geteimy.com for Shell Script SucceedsPostAction.sh

Credits

Balance and Control	Mikhail Zhigulin
Source Code	Mikhail Zhigulin
Documentation	Mikhail Zhigulin
Approbation	Mikhail Zhigulin
English	Mikhail Zhigulin

• Language support: Reverso
• Git clients: SmartGit and GitHub Desktop

Contributing

Note

The product is constructed in P2P relationship paradigm that means the only one single and the same face in the product team during all development process stages.

Bug reports are welcome, create an issue and give details.

Author

© Mikhail A. Zhigulin of Novosibirsk

Contact

E-mail • Telegram • GitHub

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