There are two things that I am aware of:
1) Files that are generated by your app (and not a result of the user using your app) such as temporary text files to store a variable's value, then these files must be placed in the Library/Cache instead of the Document directory.
2) You must also mark a file with a "skip-backup" attribute to tell iCloud not to backup the file.
I think you might be missing step 2.
I wrote a simple MediaDirectory class which quickly gives me the path to the files in the Library/Cache folder and also add the skip backup attribute.
After you saved your file to the Libary/Cache folder, you simply go something like this:
[MediaDirectory addSkipBackupAttributeForFile:@"myTextFile.txt"];
Here's the class in full:
// Header File
// ----------------------------------------------------------------------
// This class takes a file name (including extension) and returns
// the path to that file in the Library/Cache folder
// ----------------------------------------------------------------------
#import <Foundation/Foundation.h>
@interface MediaDirectory : NSObject
+(NSString *) mediaPathForFileName:(NSString *) fileName;
+(NSString *) mediaPathForFileName:(NSString *) fileName inSubDirectory:(NSString *) subDirectory;
+ (BOOL)addSkipBackupAttributeToFile:(NSString *) fileName;
+ (BOOL)addSkipBackupAttributeToFile:(NSString *) fileName inSubDirectory:(NSString *) subDirectory;
@end
// Implementation File
#import "MediaDirectory.h"
#include <sys/xattr.h>
@implementation MediaDirectory
+(NSString *) mediaPathForFileName:(NSString *) fileName
{
NSArray *directoryPaths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *cachesDirectory = [directoryPaths objectAtIndex:0];
NSString *filePath = [NSString stringWithFormat:@"%@/%@", cachesDirectory, fileName];
return filePath;
}
// if an image needs to be stored in a sub folder called "images"
+(NSString *) mediaPathForFileName:(NSString *) fileName inSubDirectory:(NSString *) subDirectory
{
NSArray *directoryPaths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
NSString *cachesDirectory = [directoryPaths objectAtIndex:0];
NSString *filePath = [NSString stringWithFormat:@"%@/%@/%@", cachesDirectory, subDirectory, fileName];
return filePath;
}
//+ (BOOL)addSkipBackupAttributeToItemAtURL:(NSURL *)URL
+ (BOOL)addSkipBackupAttributeToFile:(NSString *) fileName
{
const char* filePath = [[self mediaPathForFileName:fileName] 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;
}
+ (BOOL)addSkipBackupAttributeToFile:(NSString *) fileName inSubDirectory:(NSString *) subDirectory
{
const char* filePath = [[self mediaPathForFileName:fileName inSubDirectory:subDirectory] 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;
}
@end
