I am new to ios development so please pardon if I am asking a silly question.
I need to check if my sql file from the previous installation of the same app exists in the device directory already. If yes, then I need to fetch that file instead of making the new one. But the bundle folder of the app changes after reinstalling the app. So I cant guess the name of the previously installed app bundle folder. I tried to save it elsewhere on the device, but it isn't allowing me. Please suggest me the solution.
What you're asking for isn't possible. If an app is removed, all its files are deleted as well. In iOS, there is no app-neutral place to store files. When an app is merely updated, the update happens "in place" from the perspective of the app, and all previous files are available.
If you want files to survive a delete-reinstall cycle, you'll have to use a cloud service, such as iCloud, Dropbox or Google Drive.
once app is deleted. Application bundle and document directory and all files (including SQLite file)are deleted. u have to fetch all data from API.
In iOS each application is a Sandbox. This Sandbox consists of Application bundle and Mutable part where you store your database and other files which are mutated during the life span of an application.
When you delete the application, entire Sandbox is removed. The only thing which does not get remove is the data which you have stored in keychain.
When you update the application, only application bundle gets updated and Mutable part remain un-touched. So while re-installing the application when it is already present (technically updating the existing application on the device), you can find the same file from the same location.
You can do one thing you can take daily backup of that file on remote server and when you reinstall app check that file exist on server if exists than download else create new.
Related
I know that when you build an iOS app and package files in its bundle ready for deploying it, those files in the bundle are not meant to be changed or tempered with as it would invalidate the app signing (correct me if am wrong).
Now, what if an app is shipped with an SQLite database or CoreData Store in the bundle which the app is expected to CRUD its records. Are changes possible in this case? Will the signing be invalid? Or will I need to copy the bundled store to a different location at run time to modify it?
Hope you can clarify
Cheers
Anything in the app bundle is read-only. Period.
Your only option is to copy the read-only file from the app bundle to a writable folder the first time your app runs and then only use the writable copy.
We have stored our app sqlite database in the Library folder. We need that for future app upgrades from app store, the database included in the upgraded app to delete the database from the installed one when users download it from app store. We have checked from different sources, and they say that only the content in Documents folder will not be deleted.
Please can you confirm this point?
Thanks
The Library folder will survive an app upgrade. It's possible that Library/Caches will be deleted but not Library in general.
The simplest solution is to have the new version of your app use a different filename for the database file and have code that looks for and deletes the old database file.
I am going to publish a new version of my app on app store. I just want to know that if the app is being updated from the previous version or user has installed a fresh copy of the new version of my app. Based on this information i want to show some information to the updated users.
I was thinking of to keep a key in my NSUserDefaults of the previous_version but i haven't added any such key in the NSUserDefaults of my previous app version. So this key will be nil in both cases in my new version.
Is there a way i can get to know if the user has updated the app or installed a fresh copy of my app.
There is no direct way for it. Indirectly you can check it. If you are moving your editable data into Documents directory in your previous version then at the time of launching new application, you can check if the file is present in document directory. If you can find it, the application is opened after update and if file is not present then it has been opened because of a fresh installation.
I'm making an iPad app which will be distributed from my own web server using Enterprise Distribution Program.
The app itself checks for a newer version on the server and calls itms-services in IOS to update itself. This works perfect.
The app bundle contains a directory with resources like images and movies.
Apple claims that updates will keep the users data if the bundle-identifier is the same.
From: http://help.apple.com/iosdeployment-apps/mac/1.1/#app43ad802c
If you want users to keep the app’s data stored on their device, make sure the new version uses the same bundle-identifier as the one it’s replacing, and tell users not to delete their old version before installing the new one. The new version will replace the old one and keep data stored on the device, if the bundle-identifiers match.
When running the app from Xcode directly to my connected iPad, I can remove the folder with my resources, run the app again, and the folder remains in the bundle on my iPad.
This behavior is what i look for. I'm planning on adding more folders with new resources with new updates. Since the resources are quite heavy, I don't want users to have to download bigger and bigger archives. I want to add just the new stuff.
The problem arises when I make a new archive without the folder and update the app from my web server as users would. Then the folder seems to be deleted.
Any experience with this?
The bundle that you install is always overwritten by the new bundle that you install. The user data referred to in the documentation is the data stored in the Documents and Library folders of the file system. If you wish to be sure that the old bundle files will always be available, you can copy them from the bundle to the Library/Caches folder of the application.
One thing worth mentioning is that the way to ensure that the ad hoc installation overwrites the current bundle is to make sure that you change the bundle version.
hope this helped :)
I'm having a problem for my app, a Chinese-English dictionary. I'm now adding a wordbook for it, and try to save the contents of it to a plist every time users exit the app. But now I find that as my app updates, all these data will get lost because the path of the app is changed.
I'm now working for a company so the app will keep releasing new versions, and how can I save the data from version to version?
all these data will get lost because the path of the app is changed.
That would indicate you're writing to your application's directory structure. Don't do that.
The iPhone has a documents directory.
Document Directory discussion