I'm in the middle of making an app that will end up needing somewhere between 300-500 different images. I don't know if a database is the right way to go about this, or storing them locally. I doubt locally could do it, seeing as the app size would get huge. Would I just download all the files necessary for an event, then unload them when the event is done
TIA!
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For my latest app update, I have to move the user's Core Data .sqlite database from the Documents directory to the Application Support directory. I use the migratePersistentStore:toURL:options:withType:error: method. I am dealing with one user who somehow managed to save enough data in her database so that it is now a whopping 9G. On top of that, her device is an iPad Air 1 - which had memory issues around the time it came out five or six years ago, and now it is 2018 and she is running the latest iOS. The migratePersistentStore:toURL:options:withType:error: method keeps crashing the app with low memory. But I have no other way to get the .sqlite to the necessary location. Can anyone advise me on how to best approach this situation? Ideally, something I could do in my code - but I would even appreciate suggestions on other ways I could just help the user to manually move that massive database at this point!
I guess you use migratePersistentStore because its the official way to do it. Its a good way, but sometimes you have to make your hands dirty:
Manually-moving database at app-start before you load it
This post shows that CoreData may use more than one file which you have to move. You can list the files in the directory, use a regex find all the files which have to be moved, move them to the new location and then load CoreData as usual from the new location.
This however requires there to be the necessary infrastructure in place to do this. You‘ll figure it out if you want to go this path.
You can hide this behind a feature-flag, only with a code, only for a certain user or after crashing with low memory so it doesn‘t impact users who don‘t need it.
For some reason my boss think the bigger an IOS app is, the better it will be. I finish the app he wants but he thinks it's not good enough because it's on 13M. So what should I do, put a music in project?
You could add a big file that would not be used in app, an image, or just a data file with random data in it.
Or you could explain to your client that a smaller app is easier to download for the end user.
I'm developing a chat app with Firebase. Am currently still in development phase.
Profile pictures of test users are uploaded to Firebase Storage, and are downloaded in the home screen (with all the pictures). I realized that with that I very quickly used up storage download requests (easily hit 3,000 requests in one night, and hit the free plan quota!).
What are some best practices I could use to minimize download requests? Just to be sure I'm doing it right - I'm sending a GET request to the Firebase Storage url directly: https://firebasestorage.googleapis.com/... to download the image. Is that the right way to do it?
Two suggestions that might help:
Cache your images! If you keep requesting the same images over and over again over the network, that's going to use up your quota pretty fast. Not to mention your user's battery and network traffic. After you retrieve an image from the network, save it locally, and then the next time you need an image, look for it locally before you make another network request. Or consider using a library like PINRemoteImage that does most of the work for you. (Both on the retrieving as well as the caching side)
Consider uploading smaller versions of your image if you think you might be using them often. If your chat app, for instance, saves profile pictures as 1024x768 images, but then spend most of its time showing them as 66x50 thumbnails, you're probably downloading a lot of data you don't need. Consider saving both the original image and a thumbnail, and then grabbing the larger one only if you need it.
Hope that helps...
I'm making a catalog where the cells in my collection view will be either an image with a label or a pdf. There will be many collections and they themselves will be static. I want the user to be able to save the cells he likes and view them in his own custom view.
1) I could to store the image as data in Core Data.
2) I could just include the image in my App Bundle and load the image from there every time my app starts.
I've got it into to my head that reading data from a Core Data Store would give me more options when building my app as well as offer some boost in performance as opposed to reading it from the app bundle. Is that true? Keeping in mind of course that most of the data is static.
It seems inefficient to have images both serialized images in my app bundle and the pure data as well.
I think I'd rather have it all in the store but they have to be loaded from the bundle at some point in code right?
I'd love to know how other developers do it.
Now in Core Data there is an "allows external storage" option for binary data, which basically means if your file is bigger than 1 MB it will be stored automatically outside of your database, and you have to do nothing differently. In my opinion that's the way to get the best of both worlds, increased performance + automatization + fast queries (although they are slower than usual when you allow external storage, but still faster than doing it yourself)
My situation:
I have an app that needs to store 10,000 - 30,000 locations in some sort of storage method, which are then displayed on a MKMapView as individual pins. I also have a server that needs to be able to add to the database through pushing out changes.
Through grouping pins I've eliminated all issues with the MKMapView, my biggest focus is now on speed, storage and being able to add and replace the storage contents. What I'm currently doing is I have a text file of currently 1,000 locations as JSON-formatted, then they're just read as an array and sent to my custom map view (no issues there). My only issue is how I could update that text file (rather than downloading massive amounts of data), and store almost 30,000 locations.
Is this even feasible? It seems my current setup could scale pretty much perfectly, it's just this updating system that is causing me a headache.
Your current setup won't scale forever because you have to load the entire file into memory in one chunk. Eventually it will get to large to manage and will eat up to much memory. Unable to purge memory in the event of system low-memory, the system will shut your app down i.e. it won't be able to stay in the background but will have to reboot each time the user switches back to it.
To update, you will have to load in the entire file, parse the JSON, figure out how to update the resulting data structure, then write it all to file. One error anywhere in the process could corrupt the entire file.
You really need to look at using Core Data or even SQL. Core Data has a learning curve but once you master it, it makes implementing designs like your app trivial. You also get automatic scaling and efficient memory management.