The app that I am working on allows users to favorite podcast channels. I have been told that the best way to keep track of this is through core data. My initial thought was that it was the best way, but after giving it more thought, it seems overkill for this one feature. The way I understand Core Data is that it is Apple's recommended way of implementing the app's model layer, but we are not using it. What would you recommend to accomplish this feature? Also, we are not storing all of our data locally. The only data we are storing is the mp3 files that the user downloads, which are saved into the documents directory.
If you are persisting data (such as podcast urls, episode information, etc.) then you should store all of it in one place. Core Data can do that easily.
How much data are you storing? I would guess from your app description that you have more data than just what is a favorite.
Update
If you are storing a favorite flag you need something to associate it with. A URL perhaps.
If you are storing the URL, you might as well cache the podcast name with it.
If you are storing the name, might as well cache the episodes.
See where I am going? :)
Keep a local cache of what you are getting from the web and the user gets a better experience because they see data on launch, they don't need to wait for the internet which is random.
If you are caching data, then yes! use Core Data. Otherwise, NSUserDefaults is probably sufficient.
Related
What is a good way to store many key/value pair entries in a mobile (iOS) application, such that they can be easily exported/imported?
I have considered a single large JSON file - would this be too slow/large with 200,000+ entries?
I have also considered CoreData - but could the data be moved easily via, for example, email?
Think of an address book. Contacts can be easily imported/exported, what data storage model would be comparable?
Thank you.
EDIT: Examples
Notes - be able to select and view short notes in a table. Each note is < 100 characters.
Saved bookmarks - each bookmark is stored in a table.
I have considered a single large JSON file - would this be too
slow/large with 200,000+ entries?
I don't know. I can make a guess. The guess would be yes, it's both too large and too slow. However, you can always test it to find out.
I have also considered CoreData - but could the data be moved easily
via, for example, email?
That depends on how you want to share the data. You call email easy?
Core Data is a framework. You can use any type of backend you want (you can even write your own). The most common is probably SQLite.
If you use Core Data, you can keep the data files in a separate subdirectory and copy them just like any other file.
However, if you want to share data via an online service, you may want the ability to import/export JSON files.
If you are talking about synchronization, then that's a different beast entirely.
Basically, there is no single right answer. You have to assess your requirements, and then determine which solution meets your needs.
On the surface, it seems like using Core Data would be a good fit, but it depends on how you want to use the data in your application. Only you know that answer.
I'm working on a new iOS game and would like to save the progress online through iCloud. The saving is fairly frequent, but they are mostly doubles and ints with scores, unlocks and NSDate numbers.
Since internet will be required to play the game, I would like to save the game only online, not locally. When the app opens it should download the saved game from the server, and when it's done, launch the game.
Online currency will be sold through IAP, so I want to make sure the progress will not be lost even if the game is deleted and reinstalled, and of course, be available on multiple devices from the same user.
What's the best way to do this? Is it possible through iCloud? Key value seems like a mess because it doesn't sync quickly with iCloud. So Core Data?
I'm not looking for code to copy and paste, but I would like to create a discussion to find out the best solution for this case, if it's iCloud, setting up my own server, etc. Everywhere I look people say different things, but so far I couldn't find the best solution.
Thanks!
In iOS 8, you might want to look at GKSavedGame — it manages saved games associated with a Game Center player and syncs them through iCloud.
Otherwise, direct use of iCloud APIs sounds reasonable for your use case. If you write a small, well-defined set of values, the ubiquitous key-value store is very easy to use. If your save games are more complicated, write out a property list or encode your custom objects with NSKeyedArchiver, then use the NSFileManager APIs for syncing the resulting files through iCloud.
Going for Core Data or CloudKit is also possible, but sounds like it's more complicated than your game needs.
Im working on a multiplayer turn based game in xcode for iphone/ipad im considering my options when it comes to where to save users details such as name / points ect. I was considering creating a plist and storing data in this also i have considered nsuserdefaults and also core data.
Basically majority of the time the user will be adding new details on every launch however this will not be the case 100% of the time.
What would you guys consider the best approach?
This really depends on multiple factors:
How much data is it going to be saved?
How fast the data needs to be loaded?
I suggest you create a serializable object, that conforms to NSCoding protocol. There is also an option to save this as JSON or like you noted, plist.
I think Core Data is too much boiler plate, if this is all you are storing. NSUserDefaults is fast enough and already prepared for you to use.
I don't think someone can give you the correct answer, I suggest you experiment with all the options and see which one is the best for you.
I am making meeting app and I need to store users data. I am not need to use sql for now because it hard to setting it, so I need place to store data, I not want store users in RAM, so where can I do it? It not necessary to cache images for now, by if I can add it in this place in future it will be great.
Here is what I believe you are asking:
I am developing a meeting app and I need to store some user data.
I dont want to use sql for because its complex to do, so I need
a place to store my data. I not want use up unnecessary RAM,
so where can I store the data? I currently dont have any need
for cacheing images but perhaps in the future.
Not using CoreData/SQL because its hard to understand is not really a good reason. It was the native built in way of data access within iOS and it is the recommended way.
This is a very broad question since we dont know what your data looks like and if there are relationships between them, how large your dataset is, etc.
If its a small enough data list maybe you can look into using a PLIST. It will be a list of values with a key to each one. If its really small you can use NSUserDefaults If its static data, perhaps storing them in a NSArray or NSDictionary
First time asking a question on here, so please go easy if I don't provide enough info. Basically part of my iOS app allows users to take a picture which will be stored in a Core Data store. The attribute is a Transformable type, and I have created an NSManagedObject subclass which I simply use to set its image attribute to the new image provided by the user.
I know storing large files in Core Data is a bad idea, which is why I was excited when I saw the "Store in External Record File" option under the image attribute in the Core Data entity. However, my app performance says otherwise, taking several seconds on an iPhone 5 to load only a few images (which I know doesn't sound like much time, but considering how powerful the iPhone 5 is, older devices would likely take much longer with the same data).
I've looked around, and some people say that the Store in External Record File option is only applicable to the OS X environment, even though it is available in an iOS app. However, I also saw this under Apple's "What's New in iOS 5" doc (it's the next to last item under Core Data, near the end):
Managed objects support two significant new features: ordered relationships, and external storage for attribute values. If you specify that the value of a managed object attribute may be stored as an external record, Core Data heuristically decides on a per-value basis whether it should save the data directly in the database or store a URL to a separate file that it manages for you.
So my question is, who's right? Is it true that Apple made a mistake in giving this option for iOS apps, and that it actually does nothing unless you're on the Mac, or does it actually do something and I'm not configuring it the right way, or is it doing what it's supposed to do and the performance is bad anyway?
I've seen some guides explaining how to store large files (like images) as files, and save the URL to them in the Core Data store instead, but since this is essentially what this new option is doing, or maybe should be doing, I'm not sure if following these guides would even help.
I'm really sorry if this has been asked before. Normally I'd be fine with figuring this out on my own, but Core Data is totally new to me, and I'm still not sure how I managed to squeak by the initial setup. Thank you for any help you can offer!
who's right ?
the iOS docset for the NSAttributeDescription class does mention the allowsExternalBinaryDataStorage and the setAllowsExternalBinaryDataStorage: methods so there is little chance that there is a mistake from Apple.
are you doing something wrong or is slow anyway ?
You said that
The attribute is a Transformable type
But Core Data has a Binary data type. Maybe only this one is linked to the external storage capability.
if that's not it, we don't have enough info here:
How many pictures do you store ?
What are their sizes ?
Do you automatically fetch all the images ?
Also, the Apple doc states that:
Core Data heuristically decides on a per-value basis…
Did you use a migration or are you starting from scratch ?
You could have a look in your app's sandbox to see if your pictures are really saved outside of CoreData.
Hope this helps.
Good question!
Check this post:
Storing blobs in external location using built-in CoreData option
Apparently it should work. You should also try it in the simulator and inspect the application data folder to see if the folders are created as described (~/Library/Application Support/iPhone Simulator/... - you will figure out the rest of the path). Also you could inspect the sqlite file with the sqlite3 command to see if the binary data is in the database.
I haven't personally used this option as I would prefer to go for manually saving the images in a folder and store a reference to them in the database instead. This way it will be easier to create UIImage object from the file to be displayed, would have better control on what goes where and so on and so forth. Will take some extra labour though!
Hope that helps you out.