I just installed iOS 11 beta and I noticed that Offload App, By offloading app what will be remove Shared Directory or User Default or remove both or other than this ?
Looking for suggestions.
Thanks
Offloading lets you ”offload” the bundle (.ipa) for your app to save disk space. It will delete the ipa file (which contains your libraries and resources) and store only Documents and Data that includes shared data, UserDefaults etc..
Once we offload the app, what remains is the app icon of it with a small download pip on it to indicate that it has been offloaded .
Just by simple tapping on it, the app will get downloaded from the store and the saved Documents and Data will be integrated to the downloaded app, instead of an empty directory as it normally would with a fresh install.
This is a really great feature by Apple especially for devices with just 16GB storage. As you can see offloading the Prisma app saves me 44MB which is great. And even more, iOS can automatically offloads unused apps for us.
There is no official document(technical) available for offloading apps till the date but as the description(in setting app) says that your documents and data will be saved then I think it will save user defaults , document directories and core data - I mean all kind of data that can be stored!
It will save Shared Directory & User Defaults. Everything else will be deleted.
Related
I have developed a Flutter app that captures images using the camera and I store references to the image files using Shared Preferences.
When I upgrade the iOS app, the Shared Preference filename persists as expected, but the image no longer displays on the iOS device (and no longer seems to exist) File(_imageFileRef).existsSync() is false
For example, on iPhone, the image file is saved as
/private/var/mobile/Containers/Data/Application/580A9879-23CD-413D-A785-DB910673DF74/tmp/some_guid_image_name.jpg
When the app is upgraded, this file no longer seems to exist.
Where should I be saving the image files to in iOS so that they persist across upgrades?
The functionality works perfectly on Android devices.
Having received no answers, I delved a bit deeper and discovered that...
...the tmp directory in which the images are being written is for temporary files that do not need to persist between launches of your app. Your app should remove files from this directory when they are no longer needed; however, the system may purge this directory when your app is not running. The contents of this directory are not backed up by iTunes or iCloud.
So in order for the data to persist over app updates, I need to be writing to the Documents directory
Info obtained from here
How do I keep the users data when they get an update.
I use the Marmalade SDK to develop an app and I saved the user data to bin files and text files, I used the ram:// prefix when saving the files.
If I delete the app and get it from the app store again with the could symbol It had lost all its user data. I would like to release an update that doesn't delete the users data. The app does not come with any user data files, the app creates them as you use it.
Edit: Marmalade is cross platform but my question is for iOS only and the app has been publish, I am asking with respect to an existing app.
Deleting the app from the device, also removes it's sandbox. So any user data stored locally is deleted. This is expected behaviour.
If the user data comes from the web, then you just need to download it again.
Have you read the tutorial for dealing with files?
I have never used that sdk but:
rom for the read-only portion of your apps data area and is read only.
ram for the writable portion of your apps data area. This drive is the only drive that is guaranteed to exist across platforms
rst for a removable memory card on the phone or tablet
raw for paths that will be passed directly to the underlying operating system without modification. (not supported on all platforms)
tmp for a system temp folder, outside of the s3e data area. (system temporary folder and currently only available on iOS)
So maybe you could try rst:// and get the expected result?
My iOS app is intended to be compatible with iOS 5.0 and above, and it has iCloud capabilities turned off in it's target settings, I'm not integrating with iCloud. My app stores an sqlite file and some image files into Documents folder. The sqlite file is not downloadable, but images are.
I've read some posts from people saying that their app's submission was rejected because they don't met the iOS Data Storage Guidelines, but I'm not sure if that is only required if your app has iCloud capabilities enabled, is it? Should I set the NSURLIsExcludedFromBackupKey for my files anyway?
Thanks in advance
EDIT
I've read this here:
It is not possible to exclude data from backups on iOS 5.0. If your app must support iOS 5.0, then you will need to store your app data in Caches to avoid that data being backed up. iOS will delete your files from the Caches directory when necessary, so your app will need to degrade gracefully if it's data files are deleted.
But I need the sqlite file to be in Documents to insert data... how should I handle this?
It has nothing at all to do with whether your app uses iCloud or not. It has to do with the user performing backups to iCloud which is beyond the control of your app.
If all of the data in your app that is stored in the app sandbox is data that is created and stored by the user through the use of the app then Apple will have no problem with the data being backed up.
They have issue with replaceable files being backed up needlessly. If the database file is read-only and could be obtained from a server or the app bundle then don't let it be backed up. But if it starts out mostly empty and then gets data added as the user adds data through the app then it should be backed up. Same for the images.
I'm trying to store analytics data that is saved locally about a user's actions so it can be uploaded later when the user has an internet connection. I'd like the data to be stored locally and not deleted between subsequent opens of the app under normal circumstances. I do not want the data to be synced to iCloud. I'd also ideally like the data to be preserved between updates. It's fine if the data gets deleted in cases of low space.
I'm getting different answers from different sources about where to store the data- either in NSCachesDirectory or NSLibraryDirectory. Note NSCachesDirectory is a subdirectory of NSLibraryDirectory, eg. the filesystem looks like Application_Home/Library/Caches/.
According to the official documentation: http://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/PerformanceTuning/PerformanceTuning.html#//apple_ref/doc/uid/TP40007072-CH8-SW9 implies I should use NSCachesDirectory to store the data and it is not deleted under most circumstances. It also implies NSLibraryDirectory is synced to iCloud.
According to these answers: How can I get a writable path on the iPhone?, https://stackoverflow.com/a/5444762/340520/, When are files from NSCachesDirectory removed?, NSCachesDirectory is not preserved between app updates and claims that I must constantly recreate the NSCachesDirectory. The first answer also implies NSLibraryDirectory is the best place to store the data. However those answers are two years old.
According to the documentation and this answer: http://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/iPhoneOSProgrammingGuide/PerformanceTuning/PerformanceTuning.html#//apple_ref/doc/uid/TP40007072-CH8-SW10, https://stackoverflow.com/a/8830746/340520, NSCachesDirectory ARE preserved between app updates.
Localytics' iOS SDK stores their data in NSCachesDirectory: https://github.com/twobitlabs/Localytics-iOS/blob/master/src/LocalyticsDatabase.m
Mixpanel's iOS SDK stores their data in NSLibraryDirectory: https://github.com/mixpanel/mixpanel-iphone/blob/master/Mixpanel/Mixpanel.m
Between all these sources, I've been leaning toward using NSCachesDirectory, but I'm not confident that the data won't get regularly deleted under some circumstances.
NSCachesDirectory is the wrong place to store persistent information that you will need across app starts or even device re-starts.
To prove my point try this ...
Get a iPhone device that has only 8GB disk space.
Use your app to write a file in the NSCachesDirectory.
Start downloading random apps to fill up the disk space. Very soon you will see the Storage limit dialog shown by the OS.
Now just re-start your phone, start the app and see if you can find your file that you wrote.
If the first time you find the file, try the experiment again and you will find your file missing. During the device startup, if you see the device logs you will notice logs indicating purging directory to make space etc.
Use NSCachesDirectory to store information you can keep downloading from your server. Not information that you need to upload to your server.
The Caches directory should only be used for files that your app can easily replace if they are deleted. The Caches directory is may or may not be purged during an app update and possibly if the device runs out of storage space. Only use this for temporary files or files you can easily replace.
My first choice would be the Library/Application Support directory (NSApplicationSupportDirectory). Please note that this directory is not created by default. Your app must create it on first startup. This path is kept during app updates (like most of the app sandbox) and it is backed up via iTunes (or iCloud) device backup.
I think the best place is Library/Application Support (NSApplicationSupportDirectory) refer How do I prevent files from being backed up to iCloud and iTunes? for details.
We're building an iPad photo gallery with hundreds of images (almost 300mb in size). Having a web app will be a disadvantage because users will have to download the images every time (since Safari on ipad won't cache them I'm guessing?)
So if we built a native ios app instead, would it be possible to download newer images from the web and add it to the app in the future?
Thanks a ton for your help !
Each iPhone application has its own home directory containing Library and Documents folders, and a tmp directory for storing temporary files.
Take a look at section title: A Few Important Application Directories on The Application Runtime Environment.
I would save the your images to Application Home/Library/Caches folder.
Excerpt from Apple Docs:
Use this directory to write any application-specific support files that you want to persist between launches of the application or during application updates. Your application is generally responsible for adding and removing these files. It should also be able to re-create these files as needed because iTunes removes them during a full restoration of the device.
In iOS 2.2 and later, the contents of this directory are not backed up by iTunes.
http://iosdevelopertips.com/data-file-management/save-uiimage-object-as-a-png-or-jpeg-file.html
you could download it on first view, display at the uiimage, then save it off as above