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iOS

Oscar de la Hera Gomez
Oscar de la Hera Gomez
1,775 Points
Posted by Oscar de la Hera Gomez
Oscar de la Hera Gomez
1,775 Points

Parse.com, AFNetworking 2.3.1 and CoreData

Hi All !

I have recently been building a geolocation app using the Ribbit project as a base and I am now trying to transfer the Parse Users to a CoreData model to optimise the image/contact loading procedure.

I have ran into a series of tutorials including:

http://www.raywenderlich.com/15916/how-to-synchronize-core-data-with-a-web-service-part-1

http://www.raywenderlich.com/59255/afnetworking-2-0-tutorial (updated to iOS7)

and

https://www.parse.com/questions/using-afnetworking-with-parse-rest-api-for-post

However, all these tutorial are either out of date, do not give enough information or are too difficult to translate to iOS7. I am now starting to read about Parse caching policies but I am not sure this is the right solution.

All I want to do is take my current user and his friends and cache their information and images on the disk to optimise the app and update this once a day. Additionally, I would add/remove users to this cache if they were added or removed from the friends relations.

Finally, I would clear the cache when the user would log out.

Can anyone help me ?

2 Answers

Guilherme Juraszek
Guilherme Juraszek
3,550 Points
Guilherme Juraszek
Guilherme Juraszek
3,550 Points

Parse cache system is really poor. I've used it in a few projects and had to replace it with Parse + Manual Core Data syncronization. Parse released a new framework for offline sync for Android and they said they will release a version for iOS soon. Since you want to just cache few data I think the easy solution would be just save a plist (xml) file with a custom class User.

I made one simple application that I wrote a few months ago available at https://github.com/guidefreitas/smartquotes

The app is also available at App Store - Quotees - https://itunes.apple.com/us/app/quotees/id818547836?l=pt&ls=1&mt=8

It uses Core Data + Parse. It also uses multi core data context to update the core data objects in a background thread. This way the user interface is not blocked while synchronizing the data from Parse.

Oscar de la Hera Gomez
Oscar de la Hera Gomez
1,775 Points
Oscar de la Hera Gomez
Oscar de la Hera Gomez
1,775 Points

Thanks for the reply ! Why is it really poor ? And did you use any tutorials for Parse + Manual Core Data sync ? And do you know approximately when they'll release the iOS add-on ?

Guilherme Juraszek
Guilherme Juraszek
3,550 Points
Guilherme Juraszek
Guilherme Juraszek
3,550 Points

When I use it I found that when you add a new object it sometimes it does not invalidate de cache and you get the wrong data. You need to clear the cache manually and pull the data again. I didn't use any tutorial, I just create a Core Data managed object (like the one teached here in threehouse course) and create a "proxy" class. I edited my post with a sample app that I wrote a few months ago, it uses core data and syncs with Parse. It also uses multiple data contexes to allow core data manipulation in the backend thread (to not block the main thread, and the user screen, when adding, deleting or updating the core data objects).