Settings.bundle的DefaultValue不起作用？(NSUserDefaults)

// [YourApp]AppDelegate.m
- (BOOL)application:(UIApplication *)application 
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    
    NSString *name = [[NSUserDefaults standardUserDefaults] 
              stringForKey:@"name_preference"];
    if(!name) {
        // 加载默认配置
        [self performSelector:@selector(registerDefaultsFromSettingsBundle)];        
    }
        
    [window addSubview:viewController.view];
    [window makeKeyAndVisible];
    
    return YES;
}
// 获取默认设置
- (void)registerDefaultsFromSettingsBundle {
    NSString *settingsBundle = [[NSBundle mainBundle] pathForResource:@"Settings" ofType:@"bundle"];
    if(!settingsBundle) {
        NSLog(@"Could not find Settings.bundle");
        return;
    }
    
    NSDictionary *settings = [NSDictionary dictionaryWithContentsOfFile:[settingsBundle stringByAppendingPathComponent:@"Root.plist"]];
    NSArray *preferences = [settings objectForKey:@"PreferenceSpecifiers"];
    
    NSMutableDictionary *defaultsToRegister = [[NSMutableDictionary alloc] initWithCapacity:[preferences count]];
    for(NSDictionary *prefSpecification in preferences) {
        NSString *key = [prefSpecification objectForKey:@"Key"];
        if(key) {
            [defaultsToRegister setObject:[prefSpecification objectForKey:@"DefaultValue"] forKey:key];
        }
    }
    [[NSUserDefaults standardUserDefaults] registerDefaults:defaultsToRegister];
    [defaultsToRegister release];
}