App rejected due to localStorage issue, seeking advice.

Question

Hello everyone, Apple has rejected our application because we store files for offline viewing  under localStorage (/Documents)
This is an extract of the message, we received :
Data that can be recreated but must persist for proper functioning of your app - or because customers expect it to be available for offline use - should be marked with the "do not back up" attribute. For NSURL objects, add the NSURLIsExcludedFromBackupKey attribute to prevent the corresponding file from being backed up. For CFURLRef objects, use the corresponding kCFURLIsExcludedFromBackupKey attribute.
How can we do this with Adobe Air using Flex SDK 4.6?
+LA

Answer 1

Alright, again I must emphasize that this is not an easy thing to get going, at least it wasn't for me.  However, I have a 5.1+ solution made building on the jampot extension available here:
http://www.jampot.ie/ane/ane-ios-data-storage-set-donotbackup-attribute-for-ios5-native-ex tension/
Replacing the ANE file in the zip provided by jampot with the one linked below should then cause calls to that extension to follow the new 5.1 method.
http://bit.ly/QbeVCg
The extension documentation has more info on how to use it, but for a quick start, we use something like:
if (flash.system.Capabilities.version.substr(0,3).toUpperCase() == "IOS")
     var noBackupSetter : MobileBackup = new MobileBackup();
     var result:Boolean = noBackupSetter.doNotBackup(DataStorage.filePrivate.nativePath);
This will set the entire File.applicationStorageDirectory to DoNotBackup.  Files that are saved within the directory will obey the DoNotBackup rule for the containing folder.
Make sure you have the MobileBackup class from the files provided by jampot in your project and that you have included the native extension in your project and packaging.  If you have trouble with any of that, please reference the jampot link above, with the exception of using the 2nd link's ANE file.
Two important notes--
First, I have only had success compiling my project using this ANE on a Mac against Air 3.3 with the project pointed directly to my iOS 5.1 SDK folder, found at
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPho neOS5.1.sdk .  (I am using Xcode version 4.4.1, I do not know if this sdk is available in later versions, but it may be possible to find an upload of someone's copy on the web)
Second, the code the modified ANE uses requires iOS 5.1.  If you submit an app that uses this ANE and it is installed by a pre-5.1 device, the app will immediately crash.  To keep your app from being installed on pre-5.1 devices, modify your AppName-app.xml file in the root of your project to set the MinimumOSVersion like so:
    <iPhone>
        <InfoAdditions><![CDATA[
                              <key>UIDeviceFamily</key>
                              <array>
                                        <string>1</string>
                                        <string>2</string>
                              </array>
                              <key>MinimumOSVersion</key>
                              <string>5.1</string>
                    ]]></InfoAdditions>
        <requestedDisplayResolution>high</requestedDisplayResolution>
    </iPhone>
I'm sorry I don't have access to the changes I made to source at this time, but I will post again when I can to include the specific changes made.  There really was not much change to the objective-c code.  The hard part was getting the ANE built and working with Flash Builder.