iOS 6 local storage file appears twice - ios

I have an app that uses local storage (using sencha 'Ext.data.proxy.LocalStorage') to view some content offline. I was rejected by itunes for violating the iOS Data Storage Guidelines.
I thought it might be related to the localStorage being inside the /Documents folder in iOS before iOS 5.1. To confirm that in newer versions the document folder is empty I checked, but I still found a .file__0.localstorage.
The strange think is that the same file (but without the leading dot) also exists in the library/caches folder, where it should be.
Both have the same content.
Does anyone know how this can happen? I already asked in the Sencha Support but it does not seem to be related to the Sencha framework.
Note: I am not using PhoneGap, only Sencha.

Making a very small Hello World Application with Sencha that writes to local storage I could reproduce this behavior. It seems like on application exit, it will write a copy of the localstorage file to the /Documents folder.
This seemed suspicious to me and it reminded me of the PhoneGap patch for iOS 5.1 that backs up the localStorage file also.
With iOS 5.1 Apple started to put the localStorage file in the Library/Caches folder which broke many applications because the data was no longer reliable stored. So PhoneGap and others started to implement Workarrounds that backup the localStorage file to the documents folder and automatically restore it if needed.
Trying to find proof that Sencha does something similar, I opened up the resulting .app package and found a stbuild_template file that contains the native wrapper code. It is of course compiled, but searching for the string "localStorage" results in some interesting results like:
restoreLocalStorage
preserveLocalStorage
Could not remove source file while backing up localstorage Could not copy localstorage backup . Caches WebKit/LocalStorage .file__0.localstorage file__0.localstorage
SNLocalStoreageFix
Also I found a lot of references to NimbleKit which seems to be used internally for the packaging.
This thread also hints at a solution for the iOS 5.1 local storage problem in Sencha Touch 2.1 which is what the OP is using: http://www.sencha.com/forum/showthread.php?194674-Localstorage-and-native-iOS-5.1-apps&s=04149e771f9c4eea15cb6f6d97069ff6
All this is evidence for me that Sencha implemented a workarround for iOS 5.1 which will put the localStorage in the /Documents folder. Since you only use the localStorage file for caching, Apple rejected you because you store non-user data in /Documents.
I think using PhoneGap there is an option to disable this backup. So you might want to consider using this or ask Sencha if they have a similar option to disable it.

Related

Transfer file from iOS app to computer while debugging

For a native iOS application we are integrating a C++ library which is writing some logs to disk to json file.
During debugging, we would like to access to this logs, but currently we can only do it by downloading the whole app container to the macOS machine and searching for the file there.
Since this a very time consuming operation we were hoping that there would be some solution that would allows us to get this file quickly. I did take a look to the lldb commands, but none of them seem to let you extract a file from the phone.
Is there anyway to do this in a quick way?
Thank you
Couple options...
1 - Add debug-only code in your app to share the log file (via AirDrop would probably be a good option).
or
2 - During debug, set these two keys (in project settings / info) to Yes:
Application supports iTunes file sharing
Supports opening documents in place
Once you've done that, you can open / copy files from your app's Documents directory (assuming that's where the logs are being written) from Finder on your Mac.

MergJSON LiveCode External for iOS standalone setup

Currently we are only testing LiveCode 7.0.4 to see how it works and if we want to even use it. In our apps we need JSON from our server and have setup the mergJSON library/External in Livecode. So far, this is working very nicely in standalone tests for both MacOS and Windows. Today I started doing some simple tests on iOS and I am having a hard time with it.
I found answers where we need to use the Copy Files section in Standalone Settings, and that we need to copy the *.lcext file for mergJSON. Also watched the youtube how-to video that had mergSettings. There are no .nib files for mergJSON. Only .so, .dylib, and .dll, and the .lcext. I tried to add the .bundle file like the video, but the app will not launch, only black screen. Are other files required for mergJSON? And where do we put them? Do they stay in the same Externals folder structure or in project folder. Also, does an IOS runtime folder need to be created like in Widows/Mac? The app runs, no errors, but no JSON results are returned. I guess I am just a little confused on the Externals setup for iOS.
Just quick notes of our environment. We have Xcode 6.2 and the iOS Sdk 8.2. Live Code is 7.0.4 GPL (just testing and learning this way for now, will purchase commercial once I learn more.) I think the mergJSON I have is 1.0.15, downloaded from mergext.com. (which appears to be offline today) I have only tested on the simulator.
Thanks for any help.
You only need to include the lcext file in the copy files section of standalone settings. No need to setup a runtime folder for iOS etc.

iOS requirements for data storage (using cache folder versus marking files not to be backedup)

I got my app rejected due to violation of 2.23
After inspection, it would appear that I was indeed not a correct path for storing downloaded images and data files (i.e. files that I would prefer to have available for offline usage, but which the app can re-download again if removed by iOS)
However, after looking at:
https://developer.apple.com/library/ios/qa/qa1719/_index.html
It appears it may not even be enough to proper "cache" path for iOS > 5? Example:
/var/mobile/Applications/00000000-0000-0000-0000-000000000000/Library/Caches/'
Will using above make my app pass this requirement? Or am I forced to using the API for making files not to be backed-up?
Using the caches directory is correct if you can re-download the files. They will not be backed up. You only need to use the "do not backup" flag if the files exist in a location that normally is backed up (e.g. the documents directory).

Persistent storage (WebSQL and local storage) in iOS 6 w/ PhoneGap

The issue of iOS not persisting localStorage/WebSQL databases has been discussed frequently here and on other sites. The problem I am having is that the workarounds are so varied and have evolved over time. I have found 2 different PhoneGap plugins which use the native SQLite API, a plugin that periodically copies the SQL database to the documents directory,and even suggested settings in a Xcode .plist file that can be used to specify the location of SQL database. It's confusing because I'm not sure which solution applies best to the current point in time (iOS 6+ and Cordova 2.4+). Is this built in to Cordova now or do I still need a plugin. If so, which plugin? What about the setting the database location in an Xcode config file. Any help is deeply appreciated
Current versions of phonegap don't require a external plugin to use SQL with a sqlite database. The current code is compatible with iOS. You don't need to write/implement your own workaround, and you can be sure that phonegap will implement werever you need to get your app running (that's why the name phone-gap they will fill the GAP).
http://docs.phonegap.com/en/2.1.0/cordova_storage_storage.md.html#Storage

iOS File Storage: Solution for Not Backing Up

Like many developers, my iOS app was just rejected for having downloadable content that was being backed up to iCloud. I've searched for a clear answer to this question but have not been able to get one.
Apple says that you should implement a 'do not backup' attribute to your files, however, they also state (https://developer.apple.com/library/ios/#qa/qa1719/_index.html):
The new "do not back up" attribute will only be used by iOS 5.0.1 or later. On iOS 5.0 and earlier, applications will need to store their data in /Library/Caches to avoid having it backed up. Since this attribute is ignored on older systems, you will need to insure your app complies with the iOS Data Storage Guidelines on all versions of iOS that your application supports.
My app supports iOS 4.0 and later. Does this mean if I want to maintain support for iOS 4.0-5.0, I have no choice but to put all my content into the Caches folder? Or, can I just add the 'do not backup' attribute and keep the files in /Documents? If I have to keep the content in the Caches folder, can I prevent these files from being purged in low storage situations? Finally, are there any developers who have put files in the Caches folder and know how often they do get purged?
Any advice or help would be greatly appreciated. Thanks a lot!
The concern area is the iOS 5.0, which supports iCloud, but does not recognizes “do not backup” attribute. In this case, all the data of the app inside documents directory is likely to get backed up to iCloud. For the iOS versions below 5.x:
the iCloud backup is not valid.
the "do not back up" flag is not relevent. It would not produce any warnings during compilation.
Hence the data can be kept in the documents directory, with "do not back up" flag appropiately added to the contents (files/folders), for all the versions. The problem is for the version 5.0 only.
i think you can find similar question like this :
What is suitable location for creating sqlite file?
and as per my thinking it is better to store files in library with new directory rather than document directory..
No it's wrong that tou say. I've solved your same problem in that way. I saved my database and directory images in directory Documents/.. flagons those As do not backup as suggest by Apple. In that way for devices that are updated to 5.x or more that files are not backup to iCloud; for others there are no changes because there are no support to iCloud.
This is a best practice because files that are not concerning user we do not backup in iCloud. All other files that you don't want to redownload must be saved in Documents flagging it as do not backup. If you save it in Caches folder those are deleted in a short time when you close the app and must be redownloded when you open it again.

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