iphone:Settings.bundle返回空值

我使用的是xCode 3.2，然后移动到xCode 4.2，并从Settings.bundle获取一些值。。。它工作得很好

虽然我需要编辑Settings.bundle中的一些值，但是Root.plist文件没有显示，所以我按照以下步骤操作，但没有对文件进行任何更改

1) Click on the Settings.Bundle file, go over to the utilities window,
and look in the File Inspector.
2) Using the drop-down, change the file type to 'Application Bundle'

之后，我可以看到Root.plist，但现在无法在应用程序中获取其值。实际获取的是Null而不是值

下面是Settings.bundle的代码和图像

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
host = [defaults stringForKey:@"meter_preference"];
if(host == nil)
{
    host = @"10.20.20.1";
    DDLogError(@"Meter host is nil from NSUserDefaults, defaulting to %@", host);
}

---

从您的代码中，尝试以下内容：

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    host = [defaults stringForKey:@"meter_preference"];
    if(!host == nil)
    {
        host = @"10.20.20.1";
        DDLogError(@"Meter host is nil from NSUserDefaults, defaulting to %@", host);
    }

或

查看此链接可能会对您有所帮助

---

我得到了解决方案，只需在ApplicationIDFinishLaunchingWithOptions中调用以下代码即可初始化用户默认值。它是有效的

将第一行中的

somePropertyYouExpect

替换为用户默认设置中存储的属性

if (![[NSUserDefaults standardUserDefaults] objectForKey:@"somePropertyYouExpect"])  {

    NSString  *mainBundlePath = [[NSBundle mainBundle] bundlePath];
    NSString  *settingsPropertyListPath = [mainBundlePath
                                           stringByAppendingPathComponent:@"Settings.bundle/Root.plist"];

    NSDictionary *settingsPropertyList = [NSDictionary 
                                          dictionaryWithContentsOfFile:settingsPropertyListPath];

    NSMutableArray      *preferenceArray = [settingsPropertyList objectForKey:@"PreferenceSpecifiers"];
    NSMutableDictionary *registerableDictionary = [NSMutableDictionary dictionary];

    for (int i = 0; i < [preferenceArray count]; i++)  { 
        NSString  *key = [[preferenceArray objectAtIndex:i] objectForKey:@"Key"];

        if (key)  {
            id  value = [[preferenceArray objectAtIndex:i] objectForKey:@"DefaultValue"];
            [registerableDictionary setObject:value forKey:key];
        }
    }

    [[NSUserDefaults standardUserDefaults] registerDefaults:registerableDictionary]; 
    [[NSUserDefaults standardUserDefaults] synchronize]; 
} 

if（！[[NSUserDefaults standardUserDefaults]objectForKey:@“somePropertyYouExpect”]）{
NSString*mainBundlePath=[[NSBundle mainBundle]bundlePath]；
NSString*settingsPropertyListPath=[mainBundlePath]
stringByAppendingPathComponent:@“Settings.bundle/Root.plist”]；
NSDictionary*设置属性列表=[NSDictionary]
包含内容的字典文件：settingsPropertyListPath]；
NSMutableArray*preferenceArray=[settingsPropertyList objectForKey:@“PreferenceSpecifiers”]；
NSMutableDictionary*registerableDictionary=[NSMutableDictionary]；
对于（int i=0；i<[preferenceArray count]；i++{
NSString*key=[[preferenceArray objectAtIndex:i]objectForKey:@“key”]；
如果（关键）{
id值=[[preferenceArray objectAtIndex:i]objectForKey:@“DefaultValue”]；
[registerableDictionary setObject:值forKey:键]；
}
}
[[NSUserDefaults standardUserDefaults]registerDefaults:registerableDictionary]；
[[NSUserDefaults standardUserDefaults]同步]；
} 

XCode 6.3也存在同样的问题，但您的解决方案仍然有效。