问题 iCloud和Core Data预填充数据库

#define SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(v)  ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedAscending)
#include <sys/xattr.h>

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{

//Put this in your method

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSURL *pathURL= [NSURL fileURLWithPath:documentsDirectory];

    iOS5 = NO;
    if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(@"5.0.1")) {
        iOS5 = YES;
    }

    // Set do not backup attribute to whole folder
    if (iOS5) {
        BOOL success = [self addSkipBackupAttributeToItemAtURL:pathURL];
        if (success) 
            NSLog(@"Marked %@", pathURL);
        else
            NSLog(@"Can't marked %@", pathURL);
    }
}

- (BOOL)addSkipBackupAttributeToItemAtURL:(NSURL *)URL
{
    const char* filePath = [[URL path] fileSystemRepresentation];
    const char* attrName = "com.apple.MobileBackup";
    u_int8_t attrValue = 1;
    int result = setxattr(filePath, attrName, &attrValue, sizeof(attrValue), 0, 0);
    return result == 0;
}

你说你不使用iCloud。在这种情况下，你应该简单地移动你的 sqlite 文件到带后缀的目录 .nosync。应该这样做！

NSString *dataFileName = @"my.sqlite";
NSString *dataFileDirectoryName = @"Data.nosync";
NSString *documentsDirectoryPath = [self applicationDocumentsDirectory];
NSFileManager *fileManager = [NSFileManager defaultManager];

if ([fileManager fileExistsAtPath:[documentsDirectoryPath stringByAppendingPathComponent:dataFileDirectoryName]] == NO) {
    NSError *fileSystemError;
    [fileManager createDirectoryAtPath:[documentsDirectoryPath stringByAppendingPathComponent:dataFileDirectoryName]
           withIntermediateDirectories:YES
    attributes:nil
         error:&fileSystemError];

    if (fileSystemError != nil) {
        NSLog(@"Error creating database directory %@", fileSystemError);
    }
}

NSString *dataFilePath = [[documentsDirectoryPath
                           stringByAppendingPathComponent:dataFileDirectoryName]
                          stringByAppendingPathComponent:dataFileName];

// Move your file at dataFilePath location!

HTH。

我一直在研究这个问题并找到了关于这个主题的非常有趣的文章： http://iphoneincubator.com/blog/data-management/local-file-storage-in-ios-5

我相信如果您尝试使用/ Documents文件夹存储数据库文件，将继续被拒绝。

我建议你咬紧牙关并使用/ Cache。最糟糕的用户案例场景是他们的设备内存不足，应用程序清理后删除了DB文件。在这种情况下，当您的应用再次启动时，它应该将捆绑的DB文件复制到/ Cache中，并且用户将同步以从远程服务器获取多余的数据。这假设这是您的应用程序的工作方式。

要让您的应用程序将数据库文件从/ Documents移动到/ Cache，您可以告诉NSFileManager为您执行此操作...

#define FILE_MANAGER     [NSFileManager defaultManager]
#define DOCUMENTS_PATH   [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex: 0]
#define CACHES_PATH      [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) objectAtIndex: 0]
#define DB_DOCS_PATH     [DOCUMENTS_PATH stringByAppendingPathComponent: @"database.db"]
#define DB_PATH          [CACHES_PATH stringByAppendingPathComponent: @"database.db"]

if([FILE_MANAGER moveItemAtPath: DB_DOCS_PATH toPath:DB_PATH error:&error])
    {
        NSLog(@"SUCCESSFULLY MOVED %@ to %@",DB_DOCS_PATH,DB_PATH);
    }

这将阻止现有用户不必要地使用其iCloud存储。