I'm planning out a sort of reference book application. For each topic there will be a page with an image and text stored. I don't want to create new views in xcode for each page since there are 100+ topics, I'd rather find the easiest way to store the items in a database and then call the content to display on a view template when the user selects the topic from a list. After searching around I see that this is potentially done with Core Data or SQLite, and maybe even json, but I have not encountered a clear answer.
What's the best way to handle this sort of data?
You should create a database in Core Data and where you'd like to store images, use the response from this tutorial (conversion to Swift is left as an exercise for the reader) and store the fileName as a string.
Don't use json to store 100+ items, it will be very slow. SQL is quite fast, even though it's a mobile device.
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I am starting a new project (learning purposes) and I am trying to figure out what is the best software design pattern to use in the following scenario.
I have several data that need to be downloaded from multiple webservices and store somewhere in my app, to display it later. However each piece of data (e.g. list of teachers, students) will only be used in one or more specific view controllers (e.g. teachersViewController and studentsViewController).
I read that the Singleton pattern or use the AppDelegate to store a variable (an object like ApplicationData) is a bad practise, even more in this example which I want to restrict the data access.
So, which design pattern should I choose? I have read something about dependency injection, but I don't have any clue about it or if it even helps me in this question. If it helps, some examples with explanation would be nice.
You need some sort of database to store downloaded data. Good choices are Realm and Core Data. The right way to process data is:
Check if data is already in DB and show it if available.
Download or update data from server and parse it to objects.
Save objects to DB.
Show data taken from DB to user.
Download data as needed. When you open VC with students then download only students data and so on.
EDITED: If you need all the data on app open then load it and put in a DB before first screen opens. Then just use DB to show data to user.
I have an app similar structured to the new Notes app. A sidebar contains information about different files (date, title, excerpt) and the detail view shows the whole content.
To store data in my app, I use NSKeyedArchiver. Each file is stored seperatly to make iCloud Sync easier.
So here is my question: Is there any good way of storing and loading this data in the sidebar?
The problem is that when the app starts, it iterates through every available file to load the information needed. However, the whole object graph loads for each file even if I only need the date and the title. Is there anything I can do to optimize this?
Should I use a seperatly index file where all dates and titles are stored?
Am I using the wrong storage concept?
Any advice would be appreciated!
Sounds like what you need to do is store the key information (date and title) separately from the rest of the data.
When you start the app, you can load the key information and display it, then retrieve the rest of the data only when required, by linking the title to the content.
You could use CoreData for this - but probably overkill.
Realm will work very well for this. There's a good tutorial available here http://www.raywenderlich.com/112544/realm-tutorial-getting-started
I am taking development courses for ios and I was wondering if I wanted to create a translation app would i use a array list to do so? As example code is:-
var dictionary = [“talofa”: “hello’, “faafetai”: “thank you”]
print(dictionary[“talofa”])
it shows up in the logs as “hello” but there has to be an easier way to do translations otherwise I would be fitting a whole language in a array list?
I also read online that people have been using third party services like google to make a translation app but my language is not on google (Hawaiian) what do I do?
First of all, what you are using in your example, in swift/objc it is called a dictionary.
Secondly, for such a huge amount of data, I recommend you use some sort of persistent storage. You can use plain text to store the dictionary (like creating a .plist file), but being iOS I would recommend setting up coredata.
CoreData will allow you to store the information on the device, and access it through a data Model.
Here you can find an example on storing in a file.
Here you can find an example on storing in CoreData.
I personally recommend using coredata for such a large quantity of data. Plist files are more suitable for storing low information quantities (like saving some credentials, some settings, etc).
You need to use DB for this. You can update it from your server when user will have connection, so you don't need to re-submit your app when you will update your vocabulary.
You can use CoreData as #Alex Bartiş told you or you can try another one which becomes popular: Realm
New to iOS development..
Basically what i'm trying to do is hard code data into my app using core data. Two different types will be stored, both strings: quotes and authors (There will be around 20 of each in the app). I have a button on my Storyboard as an IBaction that when clicked will populate a label with a new quote and author. My struggle right now is 1) finding out how to create this data and 2) how to fetch this data.
Every resource i'm finding online goes through tutorials on how to store data that a user typed in and then fetch it from a button. I'm trying to figure out how to store data without user input and then fetch it. Any help is appreciated. Sorry for asking what I am sure is a pretty simple question.
Unfortunately, though this would seem like a simple task, to my knowledge there is know "built-in" way to prepopulate CoreData. You can build up a core database and then copy it into an app, or possibly use a third party solution, though. Searching for "prepopulate coredata" here and on google should give you a start.
Here's a couple threads that might help:
Any way to pre populate core data?
iOS CoreData - prepopulate db with existing indexes
I've checked a lot of sites and answers and I can't find any solutions specific to my problem.
I don't need to change the schema for my Core data model, all I need is to modify (add some) content to the current backing SQL Database.
Any direction on this will be welcome. Thanks.
PS: I tried Apple docs and they were about as useful to me as sunshine on Mecury.
Also go easy please, I'm a beginner.
Thanks.
UPDATE;
To shed more light on my issue, my app works as thus. I have preloaded static information on the app that can't be changed by the user, each day has new content. Every month, I push an update with entirely new content specific to that month. However, when my app entered production, upon the update I pushed for this month, my users were complaining that they couldn't access the month's data. This led to me spamming them with Push notifications to have them delete the app and do a fresh install to access the new data.
How can I fix this issue? my schema stays the same, only the data changes.
If I understand correctly you want to pre-fill a Core Data database ?
If you don't care about pre-existing data on existing app, you can make an iPhone or Mac app with the same model, and let it generate the database, like explain here (Any way to pre populate core data?) it's also the way recommended in a really great book if you want to learn more about Core Data (http://pragprog.com/book/mzcd2/core-data).
Do not ever make SQL request directly, Core Data work in his own magic way.
Don't work on the SQLite-Database directly. Change all your Data through NSManagedObjectContext! To find a good strategy look up examples from Batch-Importing.
Update: You could actually have two PersistentStores (one with just static data (readonly) and the other one with user-generated data). You could interchange the readonly which you prefilled with a commandline util and downloaded from a server. You cannot have direct relationships between those two store though.
I would say that it depends on the amount of data in this prefilled store wether you should go this way or just use a plist and reference some string constants in your user data store. Try to do it with a plist as this is the simpler approach.