Add alternate app icons for iOS

ComputerSolitaire.xcodeproj/project.pbxproj

@@ -216,6 +216,7 @@
 		4B75C1E02F1A233500761A12 /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				ASSETCATALOG_COMPILER_ALTERNATE_APPICON_NAMES = QueenOfHeartsAppIcon;
 				ASSETCATALOG_COMPILER_APPICON_NAME = ComputerSolitaireAppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "Apple Development";
@@ -267,6 +268,7 @@
 		4B75C1E12F1A233500761A12 /* Release */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
+				ASSETCATALOG_COMPILER_ALTERNATE_APPICON_NAMES = QueenOfHeartsAppIcon;
 				ASSETCATALOG_COMPILER_APPICON_NAME = ComputerSolitaireAppIcon;
 				ASSETCATALOG_COMPILER_GLOBAL_ACCENT_COLOR_NAME = AccentColor;
 				"CODE_SIGN_IDENTITY[sdk=macosx*]" = "Apple Development";

ComputerSolitaire/AppIcons/QueenOfHeartsAppIcon.icon/icon.json

@@ -0,0 +1,47 @@
+{
+  "fill" : {
+    "automatic-gradient" : "display-p3:0.45728,0.63330,0.83252,1.00000",
+    "orientation" : {
+      "start" : {
+        "x" : 0.5,
+        "y" : 1
+      },
+      "stop" : {
+        "x" : 0.5,
+        "y" : 0.3
+      }
+    }
+  },
+  "groups" : [
+    {
+      "layers" : [
+        {
+          "glass" : false,
+          "image-name" : "computer-solitaire.png",
+          "name" : "computer-solitaire",
+          "position" : {
+            "scale" : 0.6,
+            "translation-in-points" : [
+              0,
+              0
+            ]
+          }
+        }
+      ],
+      "shadow" : {
+        "kind" : "neutral",
+        "opacity" : 0.5
+      },
+      "translucency" : {
+        "enabled" : true,
+        "value" : 0.5
+      }
+    }
+  ],
+  "supported-platforms" : {
+    "circles" : [
+      "watchOS"
+    ],
+    "squares" : "shared"
+  }
+}

ComputerSolitaire/Assets.xcassets/AppIconPreviews/AppIconPreviewDefault.imageset/Contents.json

@@ -0,0 +1,21 @@
+{
+  "images" : [
+    {
+      "filename" : "default.png",
+      "idiom" : "universal",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

ComputerSolitaire/Assets.xcassets/AppIconPreviews/AppIconPreviewQueenOfHearts.imageset/Contents.json

@@ -0,0 +1,21 @@
+{
+  "images" : [
+    {
+      "filename" : "queen-of-hearts.png",
+      "idiom" : "universal",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

ComputerSolitaire/Assets.xcassets/AppIconPreviews/Contents.json

@@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}

ComputerSolitaire/Views/AppIconPickerView.swift

@@ -0,0 +1,158 @@
+#if os(iOS)
+import SwiftUI
+import UIKit
+
+/// To add a new alternate icon:
+/// 1. Add its Icon Composer package to `AppIcons/`.
+/// 2. Append the icon name to `ASSETCATALOG_COMPILER_ALTERNATE_APPICON_NAMES` in build settings.
+/// 3. Add a flattened preview export to `Assets.xcassets/AppIconPreviews/` and declare it below.
+struct AppIcon: Identifiable, Equatable {
+    /// The name passed to `setAlternateIconName(_:)`; `nil` selects the primary icon.
+    let alternateIconName: String?
+    let name: String
+    let previewImageName: String
+
+    var id: String { previewImageName }
+
+    static let `default` = AppIcon(
+        alternateIconName: nil,
+        name: "Default",
+        previewImageName: "AppIconPreviewDefault"
+    )
+
+    static let queenOfHearts = AppIcon(
+        alternateIconName: "QueenOfHeartsAppIcon",
+        name: "Queen of Hearts",
+        previewImageName: "AppIconPreviewQueenOfHearts"
+    )
+
+    static let all: [AppIcon] = [.default, .queenOfHearts]
+
+    static func current() -> AppIcon {
+        let activeName = UIApplication.shared.alternateIconName
+        return all.first { $0.alternateIconName == activeName } ?? .default
+    }
+}
+
+struct AppIconPreviewView: View {
+    let icon: AppIcon
+    var size: CGFloat = 56
+
+    private var shape: RoundedRectangle {
+        // Matches the home screen icon corner radius ratio.
+        RoundedRectangle(cornerRadius: size * 0.2237, style: .continuous)
+    }
+
+    var body: some View {
+        Image(icon.previewImageName)
+            .resizable()
+            .scaledToFill()
+            .frame(width: size, height: size)
+            .clipShape(shape)
+            .overlay {
+                shape.stroke(Color.primary.opacity(0.12), lineWidth: 0.5)
+            }
+    }
+}
+
+struct AppIconPickerView: View {
+    @Environment(\.dismiss) private var dismiss
+    @Binding var selection: AppIcon
+
+    private let columns = [GridItem(.adaptive(minimum: 130), spacing: 12)]
+
+    var body: some View {
+        ScrollView {
+            LazyVGrid(columns: columns, spacing: 12) {
+                ForEach(AppIcon.all) { icon in
+                    iconTile(icon)
+                }
+            }
+            .padding(24)
+        }
+        .navigationTitle("App Icon")
+        .navigationBarTitleDisplayMode(.inline)
+        .toolbar {
+            ToolbarItem(placement: .confirmationAction) {
+                Button("Done") {
+                    dismiss()
+                }
+                .keyboardShortcut(.cancelAction)
+            }
+        }
+    }
+
+    private func iconTile(_ icon: AppIcon) -> some View {
+        let isSelected = selection == icon
+
+        return Button {
+            guard !isSelected else { return }
+            HapticManager.shared.play(.settingsSelection)
+            let previous = selection
+            withAnimation(.smooth(duration: 0.3)) {
+                selection = icon
+            }
+            UIApplication.shared.setAlternateIconName(icon.alternateIconName) { error in
+                guard error != nil else { return }
+                Task { @MainActor in
+                    withAnimation(.smooth(duration: 0.3)) {
+                        selection = previous
+                    }
+                }
+            }
+        } label: {
+            VStack(spacing: 6) {
+                AppIconPreviewView(icon: icon)
+
+                Text(icon.name)
+                    .font(.caption.weight(.bold))
+            }
+            .padding(.vertical, 12)
+            .padding(.horizontal, 10)
+            .frame(maxWidth: .infinity)
+            .background {
+                RoundedRectangle(cornerRadius: 14, style: .continuous)
+                    .fill(isSelected ? .thickMaterial : .thinMaterial)
+                    .shadow(
+                        color: .black.opacity(isSelected ? 0.12 : 0.04),
+                        radius: isSelected ? 8 : 2,
+                        y: isSelected ? 4 : 1
+                    )
+            }
+            .overlay {
+                RoundedRectangle(cornerRadius: 14, style: .continuous)
+                    .stroke(
+                        Color.accentColor.opacity(isSelected ? 1 : 0),
+                        lineWidth: 2.5
+                    )
+            }
+            .overlay {
+                RoundedRectangle(cornerRadius: 14, style: .continuous)
+                    .stroke(
+                        Color.primary.opacity(isSelected ? 0 : 0.1),
+                        lineWidth: 1
+                    )
+            }
+            .overlay(alignment: .topTrailing) {
+                if isSelected {
+                    Image(systemName: "checkmark.circle.fill")
+                        .font(.system(size: 18, weight: .semibold))
+                        .symbolRenderingMode(.palette)
+                        .foregroundStyle(.white, Color.accentColor)
+                        .padding(6)
+                }
+            }
+            .contentShape(Rectangle())
+        }
+        .buttonStyle(.plain)
+        .accessibilityLabel("\(icon.name) app icon")
+        .accessibilityAddTraits(isSelected ? .isSelected : [])
+    }
+}
+
+#Preview {
+    NavigationStack {
+        AppIconPickerView(selection: .constant(.default))
+    }
+}
+#endif

ComputerSolitaire/Views/SettingsView.swift

@@ -1,5 +1,8 @@
 import Foundation
 import SwiftUI
+#if os(iOS)
+import UIKit
+#endif
 
 enum TableBackgroundColor: String, CaseIterable, Identifiable {
     case ocean = "#0671b7"
@@ -84,6 +87,10 @@ struct SettingsView: View {
     @AppStorage(SettingsKey.soundEffectsEnabled) private var isSoundEffectsEnabled = true
     @AppStorage(SettingsKey.showHintButton) private var isHintButtonVisible = true
     @AppStorage(SettingsKey.cardStyle) private var cardStyleRawValue = CardStyle.classic.rawValue
+#if os(iOS)
+    @State private var selectedAppIcon = AppIcon.current()
+    @State private var isShowingAppIconPicker = false
+#endif
 
     var body: some View {
         ScrollView {
@@ -197,6 +204,28 @@ struct SettingsView: View {
                     }
                 }
 
+#if os(iOS)
+                if UIApplication.shared.supportsAlternateIcons {
+                    SettingsCard(title: "App Icon") {
+                        Button {
+                            isShowingAppIconPicker = true
+                        } label: {
+                            HStack(spacing: 10) {
+                                AppIconPreviewView(icon: selectedAppIcon, size: 30)
+                                Text(selectedAppIcon.name)
+                                    .font(.subheadline.weight(.semibold))
+                                Spacer()
+                                Image(systemName: "chevron.right")
+                                    .font(.caption.weight(.semibold))
+                                    .foregroundStyle(.secondary)
+                            }
+                            .contentShape(Rectangle())
+                        }
+                        .buttonStyle(.plain)
+                    }
+                }
+#endif
+
                 SettingsCard(title: "Help") {
                     Button {
                         isShowingRulesAndScoring = true
@@ -234,6 +263,14 @@ struct SettingsView: View {
                 RulesAndScoringView()
             }
         }
+#if os(iOS)
+        .sheet(isPresented: $isShowingAppIconPicker) {
+            NavigationStack {
+                AppIconPickerView(selection: $selectedAppIcon)
+            }
+            .presentationDetents([.medium, .large])
+        }
+#endif
         .onChange(of: drawModeRawValue) { oldValue, newValue in
             guard oldValue != newValue else { return }
             HapticManager.shared.play(.settingsSelection)