iOS অ্যাপে ডার্ক বা লাইট থিম সুইচ অপশন – SwiftUI

  var body: some Scene {
        WindowGroup {
            ContentView()
                .preferredColorScheme(.dark)
        }
    }

enum AppTheme: String, CaseIterable {
    case system
    case light
    case dark

    var colorScheme: ColorScheme? {
        switch self {
        case .system:
            return nil
        case .light:
            return .light
        case .dark:
            return .dark
        }
    }
}

import SwiftUI

@main
struct ThemeSwitchApp: App {
    @AppStorage("selectedTheme") private var selectedTheme: String = AppTheme.system.rawValue
    var body: some Scene {
        WindowGroup {
            ContentView()
                .preferredColorScheme(AppTheme(rawValue: selectedTheme)?.colorScheme)
        }
    }
}

import SwiftUI

struct ContentView: View {
    
    // initially set system theme.
    @AppStorage("selectedTheme") private var selectedTheme: String = AppTheme.system.rawValue
    
    var body: some View {
        VStack {
            Picker("Select Theme", selection: $selectedTheme) {
                ForEach(AppTheme.allCases, id: \.self) { theme in
                    Text(theme.rawValue.capitalized).tag(theme.rawValue)
                }
            }
            .pickerStyle(SegmentedPickerStyle())
            
        }
        .padding()
    }
}

import SwiftUI

@main
struct ThemeSwitchApp: App {
 @AppStorage("isDarkMode") private var isDarkMode: Bool = false 
    var body: some Scene {
        WindowGroup {
            ContentView()
                .preferredColorScheme(isDarkMode ? .dark : .light)
        }
    }
}

import SwiftUI

struct ContentView: View {
    @AppStorage("isDarkMode") private var isDarkMode: Bool = false
    var body: some View {
        VStack {
            Toggle("Enable / Disable Dark Mode", isOn: $isDarkMode)
        }
        .padding()
    }
}