Where to store large files fetched initially in a IOS App - ios

Question

My app downloads at start a sqlite database about 300MB. After the download is done, this sqlite database should be available during the installtime of the app (years :-)) . I don't know where to store this files.
I started to store the data in the library path as follow (swift)
var sDataPath = NSSearchPathForDirectoriesInDomains(.LibraryDirectory, .UserDomainMask, true);
No I realize that this path changes during development and testing with the IOS Simulator. Example:
1. I start the app the first time in OIS Simulator. The Evaluated Path is
[/Users/user/Library/Developer/CoreSimulator/Devices/19E2CB7E-3ABB-4C0A-8B49-39A0BE392A93/data/Containers/Data/Application/5EE51B55-0A89-45FB-A1E2-9BE3DCD33463/Library]
2. The App downloads the data. This takes some minutes.
3. I close the simulator and restart also xcode
4. I start the app again in the simulator and expect to have the already downloaded data in my apps' library path. But no ...
5. the app evaluates a new path, which has another ID in the Path:
[/Users/user/Library/Developer/CoreSimulator/Devices/19E2CB7E-3ABB-4C0A-8B49-39A0BE392A93/data/Containers/Data/Application/429206E9-00EA-45EF-BE6E-4B2E9374BAF5/Library]
6. And the app downloads the content again.
I would like to have a static path over the lifetime of the device. What am I doing wrong or what should I change ?

Answer 1

The path is changing on the simulator but it will be the same on a real device.
If I'm not wrong, on the simulator the path change every time you restart it. On a device the path will change only if you delete and reinstall your application.

Answer 2

You should save downloaded image to document directory. In this way images can load fastly. If u want to overcome of reloading cell then you have to check for then file path whether is fill is there or not.
- (NSString *)documentsPathForFileName:(NSString *)name folder:(NSString*)folderName{
return [[self pathToPatientPhotoFolder:folderName] stringByAppendingPathComponent:name];
}
- (NSString *)pathToPatientPhotoFolder:(NSString *)folderName {
NSString *documentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,
NSUserDomainMask,
YES) lastObject];
NSString *patientPhotoFolder = [documentsDirectory stringByAppendingPathComponent:folderName];
// Create the folder if necessary
BOOL isDir = NO;
NSFileManager *fileManager = [[NSFileManager alloc] init];
if (![fileManager fileExistsAtPath:patientPhotoFolder
isDirectory:&isDir] && isDir == NO) {
[fileManager createDirectoryAtPath:patientPhotoFolder
withIntermediateDirectories:NO
attributes:nil
error:nil];
}
return patientPhotoFolder;
}
in your cellForRowAtIndexPath: method
{…..
NSURL *urla = [NSURL URLWithString:[NSString stringWithFormat:#"%#",[self.imagearray objectAtIndex:indexPath.item]]];
NSString *thumbnailCacheKey = [NSString stringWithFormat:#"thumb-%#",[self.imageIDarray objectAtIndex:indexPath.item]];;
UIImage *image = [UIImage imageWithContentsOfFile:[self documentsPathForFileName:thumbnailCacheKey folder:#"thumb"]];
if (!image){
//first download image here and then save that image like:
NSString *stringPath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)objectAtIndex:0]stringByAppendingPathComponent:#"thumb"];
// New Folder is your folder name
NSError *error = nil;
if (![[NSFileManager defaultManager] fileExistsAtPath:stringPath])
[[NSFileManager defaultManager] createDirectoryAtPath:stringPath withIntermediateDirectories:NO attributes:nil error:&error];
NSString *filePath = [stringPath stringByAppendingPathComponent:thumbnailCacheKey];
NSData *pngData = UIImageJPEGRepresentation(image, 0.8);
[pngData writeToFile:filePath atomically:YES];
}
else{// image is already downloaded, so just set that image
cell.imageView.image = image;
}
….
}
This code creates folder in your DocumentDirectory and save image there and fetch from there. I save with one unique photoID so that image can not be same. You can save with your requirement.

Answer 3

You should store it on Cache folder.
NSString *cachesPath = [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) lastObject];
NSString *cacheFile = [cachesPath stringByAppendingPathComponent:#"file.plist"];
Store large file in other directory will be rejected by apple app review team (as i have faced)