Using NSTemporaryDirectory without increasing tmp folder size - ios

In my app the user has the possibility to upload and download 700*700mb images. These images are downloaded and displayed in a few UIImageViews.
My app itself is quite small, but the Documents & Data folder is enormous e.g. 17gb and it keeps increasing exponentially. My app runs on both ipad and on iPhone. Will the docs & data folder in my ipad is 6mb, on my ipod it is 17gb. I have downloaded the app package, and found out that the tmp folder is huge. there are some Stack-log files 1gb big. I found out the problem was related to the NSTemporarydirectory.
I save an image in this way:
NSString *title = [[NSUserDefaults standardUserDefaults]objectForKey:#"Folder3"];
PhotoiPhoneViewController* sharedSingleton = [PhotoiPhoneViewController sharedManager];
NSString *destDir = [[NSUserDefaults standardUserDefaults]objectForKey:#"Folder2"];
NSString *filename3 = [NSString stringWithFormat:#"%#%#sizefile.pages.%#", destDir, title, sharedSingleton.tagString];
NSString *SizePath = [NSTemporaryDirectory() stringByAppendingPathComponent:[NSString stringWithFormat:#"%#sizefile.pages.%#", title, sharedSingleton.tagString]];
[self.restClient loadFile:filename3 intoPath:SizePath];
Is this the right way to do it, or should I use:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *CommentPath = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:#"%#commentfile.txt.%ld", title, (long)sharedSingleton.tagNumber]]
Since I want the files to be deleted after use, I thought that the NStemporaryDirectory would be deleted as soon as the file was used. What should I do??

You could look into using NSURLCache as these manage the purging.
See also NSHipster/NSURLCache
Or you could use a library like SDWebImage which will handle a cache size as well
Edit: In answer to your question
The operating system used to leave files in the temporary directory, however, since iOS 5.0 it will purge files from this directory if it sees the need. See this link for more information

Related

Write to a file. Functional in the simulator and not functional on a real iphone [duplicate]

I am trying to take content from one file and write it into another. I am reading fine, but I am not able to write it into another file.
I have a database of words. I want to separate the words into different files based on the number of letters. All four letter words go into one file, and so on. I added a txt file called "4letter" into my resources and the following is my code:
NSError *error;
//READ
NSString *dbFile = [[NSBundle mainBundle] pathForResource:#"words" ofType:#"txt"];
NSString *test = [NSString stringWithContentsOfFile:dbFile encoding:NSUTF8StringEncoding error:&error];
//convert from string to array
NSArray *lines = [test componentsSeparatedByString:#"\n"];
NSFileHandle *logFile = nil;
logFile = [NSFileHandle fileHandleForWritingAtPath:[[NSBundle mainBundle] pathForResource:#"4letter" ofType:#"txt"]];
//Test if write works
for (int i=0; i<5; i++)
{
NSString *randomAnagram = [[lines objectAtIndex:i] lowercaseString];
[logFile writeData: [randomAnagram dataUsingEncoding: NSNEXTSTEPStringEncoding]];
}
In iOS, you can't write into a file in your app's bundle -- the entire bundle is read-only. Use a path into the Documents folder instead.
See special File System Programming Guide for better understnading.
In iOS, you can't write into a file in your app's bundle -- the entire bundle is read-only.
Consider reading iOS Data Storage Guidelines to better understand the purpose of directories below, in context of iCloud backup.
<Application_Home>/AppName.app
This is the bundle directory containing the app itself. Do not write
anything to this directory. To prevent tampering, the bundle directory
is signed at installation time. Writing to this directory changes the
signature and prevents your app from launching again.
<Application_Home>/Documents/
Use this directory to store critical user documents and app data
files. Critical data is any data that cannot be recreated by your app,
such as user-generated content. The contents of this directory can be
made available to the user through file sharing. The contents of this
directory are backed up by iTunes.
<Application_Home>/Library/
This directory is the top-level directory for files that are not user
data files. You typically put files in one of several standard
subdirectories but you can also create custom subdirectories for files
you want backed up but not exposed to the user. You should not use
this directory for user data files. The contents of this directory
(with the exception of the Caches subdirectory) are backed up by
iTunes. For additional information about the Library directory, see
“The Library Directory Stores App-Specific Files.”
See full list (tmp/, Documents/Inbox) in iOS Standard Directories: Where Files Reside
UPDATE
I use NSFileManager method URLForDirectory:inDomain:appropriateForURL:create:error:
Like Caleb said, you can't write to your app's directory, but you can write to your app's Documents folder. You can get it like this:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
Your app's bundle is read-only. There is two ways I could see:
1) Write in documents folder:
NSArray *pathList = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path =  [myPathList  objectAtIndex:0];
2) Use sqlite database. This is the same as 1 (you must save db in documents anyway), but you're using sqlite database. I think this is better than a lot of txt and plist files: here's a tutorial on the topic.
I use the following code :
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:#"set.txt"];
NSString *data=#"Kostas";
[data writeToFile:appFile atomically:YES];
NSString *myData = [NSString stringWithContentsOfFile:appFile];
NSLog(#"Data : %# ",myData);

Writing big file on IOS [duplicate]

I save some run-time generated files inside the .app bundle of my iOS app. In the simulator it works fine, in the device it crashes:
Could create output files in the given shader cache path
'/var/mobile/Applications/CB064997-B40E-4FE3-9834-B3217CE33489/SimedTest.app/Ogre3D/assets/RTShaderLib/cache/
Is there a good overview of where I should and shouldn't put files - how to use Documents, Library and tmp, etc?
To clarify, these are files created at startup which pre-calculate some data to save time. IF they are not present they get created so it's fine they are deleted, but not while the app is running.
The bundle is read-only. You don't want to mess around with it for two reasons:
Code Signing: the signature is verified by against the contents of the bundle; if you mess around with the bundle, you break the signature.
App Updates: updates work by replacing the entire app bundle with a newly downloaded one; any changes you make will get lost.
Where you should save stuff:
Documents: if you want it to persist and be backed up
Library/Caches: if you just want to cache downloaded data, like profile pics; will be auto deleted by the system if it is low on room unless you specify with a special do-not-delete flag.
tmp: temporary files, deleted when your app is not running
For a full explanation check out File System Programming Guide and QA1719.
No, every time you change your bundle you invalidate your signature.
If you want to write files you`l need to write in the best folder depending on what you want to do with that file.
Documents folder for long duration files
Cache for small operations
and so on
EDIT
To get the path you`ll need something like this:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *path = [documentsDirectory stringByAppendingPathComponent:#"filename.ext"];
With this path you can write or read like this:
write:
NSString *content = #"One\nTwo\nThree\nFour\nFive";
[content writeToFile:fileName atomically:NO encoding:NSStringEncodingConversionAllowLossy error:nil];
read:
NSString *content = [[NSString alloc] initWithContentsOfFile:fileName usedEncoding:nil error:nil];

Can't modify file programmatically objective-c [duplicate]

I am trying to take content from one file and write it into another. I am reading fine, but I am not able to write it into another file.
I have a database of words. I want to separate the words into different files based on the number of letters. All four letter words go into one file, and so on. I added a txt file called "4letter" into my resources and the following is my code:
NSError *error;
//READ
NSString *dbFile = [[NSBundle mainBundle] pathForResource:#"words" ofType:#"txt"];
NSString *test = [NSString stringWithContentsOfFile:dbFile encoding:NSUTF8StringEncoding error:&error];
//convert from string to array
NSArray *lines = [test componentsSeparatedByString:#"\n"];
NSFileHandle *logFile = nil;
logFile = [NSFileHandle fileHandleForWritingAtPath:[[NSBundle mainBundle] pathForResource:#"4letter" ofType:#"txt"]];
//Test if write works
for (int i=0; i<5; i++)
{
NSString *randomAnagram = [[lines objectAtIndex:i] lowercaseString];
[logFile writeData: [randomAnagram dataUsingEncoding: NSNEXTSTEPStringEncoding]];
}
In iOS, you can't write into a file in your app's bundle -- the entire bundle is read-only. Use a path into the Documents folder instead.
See special File System Programming Guide for better understnading.
In iOS, you can't write into a file in your app's bundle -- the entire bundle is read-only.
Consider reading iOS Data Storage Guidelines to better understand the purpose of directories below, in context of iCloud backup.
<Application_Home>/AppName.app
This is the bundle directory containing the app itself. Do not write
anything to this directory. To prevent tampering, the bundle directory
is signed at installation time. Writing to this directory changes the
signature and prevents your app from launching again.
<Application_Home>/Documents/
Use this directory to store critical user documents and app data
files. Critical data is any data that cannot be recreated by your app,
such as user-generated content. The contents of this directory can be
made available to the user through file sharing. The contents of this
directory are backed up by iTunes.
<Application_Home>/Library/
This directory is the top-level directory for files that are not user
data files. You typically put files in one of several standard
subdirectories but you can also create custom subdirectories for files
you want backed up but not exposed to the user. You should not use
this directory for user data files. The contents of this directory
(with the exception of the Caches subdirectory) are backed up by
iTunes. For additional information about the Library directory, see
“The Library Directory Stores App-Specific Files.”
See full list (tmp/, Documents/Inbox) in iOS Standard Directories: Where Files Reside
UPDATE
I use NSFileManager method URLForDirectory:inDomain:appropriateForURL:create:error:
Like Caleb said, you can't write to your app's directory, but you can write to your app's Documents folder. You can get it like this:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
Your app's bundle is read-only. There is two ways I could see:
1) Write in documents folder:
NSArray *pathList = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *path =  [myPathList  objectAtIndex:0];
2) Use sqlite database. This is the same as 1 (you must save db in documents anyway), but you're using sqlite database. I think this is better than a lot of txt and plist files: here's a tutorial on the topic.
I use the following code :
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *appFile = [documentsDirectory stringByAppendingPathComponent:#"set.txt"];
NSString *data=#"Kostas";
[data writeToFile:appFile atomically:YES];
NSString *myData = [NSString stringWithContentsOfFile:appFile];
NSLog(#"Data : %# ",myData);

itunes file share restore deleted files

My app uses iTunes File Share. I used the code to delete a single file:
It worked the first time. On the second try, however, iTunes showed a empty share directory. It turns out all data files are gone. Can I recover those data files from the iPad? Thanks
- (void) deleteFileFromDisk: (NSString*) fileName {
if([self fileExists: fileName]) {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) ;
NSString *documentsDirectory = [paths objectAtIndex: 0];
NSString* theFile = [documentsDirectory stringByAppendingPathComponent: fileName];
NSError *error;
[[NSFileManager defaultManager] removeItemAtPath: theFile error: &error];
There's no "restore" feature on the iPad. But in all probability there's nothing to worry about.
There's nothing about your code that would delete multiple files. It would delete just that file from the Documents directory that you supplied the name of as fileName. If you didn't call deleteFileFromDisk: multiple times, you didn't delete multiple files.
Perhaps at some point you deleted the app. That would delete its entire sandbox and thus would take with it anything in the Documents directory. That sort of thing is perfectly normal during repeated testing.

add pictures to the project through a zip

I have an application that takes up too much space and I would like to lower the weight, so I had decided to put all the images in a zip file and install it in the application rather than adding the images to the project. Is it possible, or does someone have a better idea? thanks
Compressing the images by putting them in a zip, given they're already in a compressed format (.jpg, .gif, .png, etc.), should not yield any appreciable gain in the size of the app, considering the effort to build the mechanism, the time it takes to unzip the files and the space in memory to keep a copy of the ucompressed files.
I would rather suggest compressing properly the images, by reducing the quality or trying with different file formats (like JPG2000).
You can use this and unzip the files within your app:
- (void)UnzippingZipFile {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *outputPath = [documentsDirectory stringByAppendingPathComponent:#"/FolderName"];
NSString *filePath = [NSString stringWithFormat:#"%#/%#", documentsDirectory,#"ZipFile.zip"];
NSString *zipPath = filePath;
[SSZipArchive unzipFileAtPath:zipPath toDestination:outputPath delegate:self];
}

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