iOS 獲取 App Icon 與 Launch Image 名稱完整指南：Info.plist 解析與適配邏輯

核心入口：Info.plist 解析

所有 App 圖標與啟動圖資訊均儲存於 `Info.plist`，通過 `[[NSBundle mainBundle] infoDictionary]` 獲取：

• App Icon：`CFBundleIcons` → `CFBundlePrimaryIcon` → `CFBundleIconFiles` (陣列)
• Launch Image：`UILaunchImages` (陣列，每項含名稱、尺寸、方向、最低系統版本)

獲取 App Icon 名稱

- (NSString *)primaryIconName {
    NSDictionary *infoDict = [[NSBundle mainBundle] infoDictionary];
    NSArray *iconFiles = infoDict[@"CFBundleIcons"][@"CFBundlePrimaryIcon"][@"CFBundleIconFiles"];
    // 最後一個通常為最高解析度（如 AppIcon60x60@3x）
    return iconFiles.lastObject;
}

// 打印所有 Icon 檔名
NSLog(@"Icon files: %@", iconFiles);
// 輸出: ( "AppIcon29x29", "AppIcon40x40", "AppIcon60x60", "AppIcon76x76", "AppIcon83.5x83.5" )

獲取 Launch Image 名稱（含邏輯適配）

方案一：手動匹配裝置尺寸與方向（完全可控）

- (NSString *)launchImageNameForCurrentDevice {
    CGFloat screenH = [UIScreen mainScreen].bounds.size.height;
    CGFloat screenW = [UIScreen mainScreen].bounds.size.width;
    UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;
    BOOL isPortrait = UIInterfaceOrientationIsPortrait(orientation);
    BOOL isLandscape = UIInterfaceOrientationIsLandscape(orientation);
    
    NSString *name = nil;
    if ((isPortrait && screenH == 480) || (isLandscape && screenW == 480)) {
        name = @"LaunchImage-700"; // iPhone 4/4S
    } else if ((isPortrait && screenH == 568) || (isLandscape && screenW == 568)) {
        name = @"LaunchImage-700-568h"; // iPhone 5/5s/SE1
    } else if ((isPortrait && screenH == 667) || (isLandscape && screenW == 667)) {
        name = @"LaunchImage-800-667h"; // iPhone 6/6s/7/8/SE2/SE3
    } else if (isPortrait && screenH == 736) {
        name = @"LaunchImage-800-Portrait-736h"; // 6/7/8 Plus 豎屏
    } else if (isLandscape && screenW == 736) {
        name = @"LaunchImage-800-Landscape-736h"; // Plus 橫屏
    } else if (isPortrait && screenH == 1024) {
        name = @"LaunchImage-700-Portrait"; // iPad 豎屏
    } else if (isLandscape && screenW == 1024) {
        name = @"LaunchImage-700-Landscape"; // iPad 橫屏
    }
    // 刘海屏、iPad Pro 等需補充對應尺寸
    return name;
}

// 用法：設置為背景圖
UIImage *img = [UIImage imageNamed:[self launchImageNameForCurrentDevice]];
self.view.backgroundColor = [UIColor colorWithPatternImage:img];

方案二：動態解析 UILaunchImages（自適應配置變更）

- (NSString *)launchImageNameFromPlist {
    NSDictionary *infoDict = [[NSBundle mainBundle] infoDictionary];
    NSArray *launchImages = infoDict[@"UILaunchImages"];
    
    CGSize screenSize = [UIScreen mainScreen].bounds.size;
    UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;
    NSString *orientationStr = UIInterfaceOrientationIsPortrait(orientation) ? @"Portrait" : @"Landscape";
    
    for (NSDictionary *imgInfo in launchImages) {
        CGSize size = CGSizeFromString(imgInfo[@"UILaunchImageSize"]);
        NSString *imgOrientation = imgInfo[@"UILaunchImageOrientation"];
        // 匹配尺寸與方向（寬高需考慮縮放比例）
        if (CGSizeEqualToSize(size, screenSize) && [imgOrientation isEqualToString:orientationStr]) {
            return imgInfo[@"UILaunchImageName"];
        }
    }
    return nil;
}

UILaunchImages 結構示例

UILaunchImages = (
    {
        UILaunchImageMinimumOSVersion = "8.0";
        UILaunchImageName = "LaunchImage-800-Portrait-736h";
        UILaunchImageOrientation = Portrait;
        UILaunchImageSize = "{414, 736}";
    },
    {
        UILaunchImageMinimumOSVersion = "7.0";
        UILaunchImageName = "LaunchImage-700-Portrait";
        UILaunchImageOrientation = Portrait;
        UILaunchImageSize = "{768, 1024}";
    },
    ...
);

完整 Info.plist 關鍵鍵值速查

現代最佳實踐：LaunchScreen.storyboard

iOS 8+ 強烈建議使用 LaunchScreen.storyboard 替代靜態圖片集：

• 單一檔案適配所有裝置、方向、分辨率、深色模式
• 支援 Auto Layout、安全區域、動態字體
• 編譯時優化，無需維護數十張圖片
• 避免 App 包體積膨脹

/* LaunchScreen.storyboard 典型結構 */
- View Controller
  - View (背景色/圖片)
    - Image View (Logo, 居中約束)
    - Label (版本號, 底部約束)

常見場景應用

避坑指南

1. ❌ 硬編碼圖片名稱 → 裝置適配失敗、維護地獄
2. ❌ 忽略 `@2x/@3x` 後綴 → 系統自動追加，代碼中只需基礎名稱
3. ❌ 混淆 `UILaunchImageSize` (points) 與像素尺寸 → 需乘以 `[UIScreen mainScreen].scale`
4. ✅ 優先使用 LaunchScreen.storyboard
5. ✅ 動態解析 Info.plist 而非寫死邏輯
6. ✅ 測試覆蓋：iPhone SE/Plus/刘海屏、iPad/Pro、豎橫屏、分屏