I've made an app that is relying on reading and writing a plist-file. This works well when I'm running the app in the iPhone simulator, but doesn't work at all when I'm testing it on my iPhone. I've also made a pre made text file in .txt format with demo data. The app works when I'm running this file.
All the reading and writing is done in a class that looks like this:
-(void)saveArray:(NSMutableArray *)inputArray
{
albumArray = inputArray;
NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentFolder = [path objectAtIndex:0];
NSString *filePath = [documentFolder stringByAppendingFormat:#"albums.plist"];
[albumArray writeToFile:filePath atomically:YES];
}
Update: Changed the string from "stringByAppendingFormat" to "stringByAppendingPathComponent" and it seems to work now. Thanks a lot! You guys made my day made.
Are you sure, that the folders already exist?
Here is a function i'm using to get the path to my file:
- (NSString*) pathToSavedAlbums
{
NSURL *applicationSupportURL = [self applicationDataDirectory];
if (! [[NSFileManager defaultManager] fileExistsAtPath:[applicationSupportURL path]])
{
NSError *error = nil;
[[NSFileManager defaultManager] createDirectoryAtPath:[applicationSupportURL path]
withIntermediateDirectories:YES
attributes:nil
error:&error];
if (error)
{
NSLog(#"error creating app support dir: %#", error);
}
}
NSString *path = [[applicationSupportURL path] stringByAppendingPathComponent:#"albums.plist"];
return path;
}
Check the spelling of the plist name as well as the case, device is case sensitive for docs but simulator isn't. Also try deleting the app from the device and reinstalling it ?
writeToFile:atomically: returns a bool, so check that to see if it fails to even write to the path. Check the file path string and ensure this is where you want it to go.
Related
I'm using the following code below save an image locally. It works without any errors, and I can preview the incoming image. The only problem is that the image never seems to actually be saved or appear in the Images directory. I use iExplorer to double check, and I have refreshed the folder and the image is still not there. Your thoughts are appreciated.
// I can preview this UIImage and it appears as expected
UIImage *image = [UIImage imageWithData:responseObject]; //responseImage is an image from online
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
NSString *docs = [paths objectAtIndex:0];
NSString* path = [docs stringByAppendingFormat:#"/Images/image1.jpg"];
NSData* imageData = [NSData dataWithData:UIImageJPEGRepresentation(image, .8)];
NSError *writeError = nil;
if(![imageData writeToFile:path options:NSDataWritingAtomic error:&writeError]) {
//This never fires, so you would think the image would have saved, but that does not appear to be the case!
NSLog(#"%#: Error saving image: %#", [self class], [writeError localizedDescription]);
}
I did also check to see if the file exists programmatically and apparently it does exist. However, when I try to reference it within a UIWebview, it doesn't load anything for that image.
Remember that NSFileManagers use NSString paths to read/write files, however UIWebViews use NSURLs. In order for you to load the file into a UIWebView, you'll need to convert your NSString path into an NSURL file URL.
So instead of something that looks like:
/Documents/Path/To/File.png
It needs to be
file:///Documents/Path/To/File.png
I believe the correct way to do this is to use the [NSURL fileURLWithPath:] method.
So it would look something like this:
NSFileManager* fileManager = [NSFileManager defaultManager];
NSString* path; //However you got your path here
if([fileManager fileExistsAtPath:path])
{
NSURL* fileURL = [NSURL fileURLWithPath:path];
NSURLRequest* request = [NSURLRequest requestWithURL: fileURL];
[_myWebView loadRequest:request];
}
This is too long to post as a comment, so I'm posting it as an answer.
I'm not sure about your if statement there. It does return a BOOL NO if the file operation fails, but I'm not exactly sure what "the operation fails" means. Just because the file is not written out does not necessarily mean that the operation failed. So it's better to check the NSError itself.
Instead of checking ![writeToFile], run the line without the if statement, and then check if(writeError != nil). If the if statement is true, then something went wrong, and if so, you can check the localized description of the error.
So to recap,
NSError* writeError = nil;
[imageData writeToFile:path options:NSDataWritingAtomic error:&writeError];
if(writeError != nil)
{
//Something went wrong
NSLog("File write error: %#", writeError.localizedDescription);
}
I´m writing certain values to a file. See Write Operations below.
This works fine when using iPad 6.1 Simulator.
When trying the same thing on my iPad it fails. I think it´s something with sandboxing. I haven´t found out yet which path is best on iOS Devices to write stuff for internal use.
Any ideas?
#pragma mark Write Operations to Tmp Folder
- (BOOL) psWriteFileWithName: (NSString*) fileName
withString:(NSString*) string {
NSString *fileName = #"artistNumber";
NSError * error = NULL;
NSString *filePath = [NSString stringWithFormat:#"/tmp/%#.txt",fileName];
[string writeToFile:filePath
atomically:YES
encoding: NSUTF8StringEncoding
error:&error];
return YES;
}
You cannot write to /tmp since this is outside of your app sandbox.
However your app also has a temp directory, which can be referenced with the NSTemporaryDirectory() function:
Which works like:
NSString *tempfilePath = [NSTemporaryDirectory() stringByAppendingPathComponent:filename];
Here is you method with the correct NSTemporaryDirectory() implementation, also edit some error handling:
#pragma mark Write Operations to Tmp Folder
- (BOOL) psWriteFileWithName: (NSString*) fileName
withString:(NSString*) string {
NSString *fileName = #"artistNumber";
NSError *error = nil;
NSString *filePath = [NSTemporaryDirectory() stringByAppendingPathComponent:filename];
if (![string writeToFile:filePath atomically:YES encoding:NSUTF8StringEncoding error:&error] ) {
NSLog(#"Error writing file: %#", error);
return NO;
}
return YES;
}
I am a beginner using Objective-C. I used the following code to move a file to iCloud but it gives an error that The operation could not be completed. The file exists.
//store the file locally in document folder
NSArray *docPaths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *filePath = [docPaths objectAtIndex:0];
filePath = [filePath stringByAppendingString:#"/"];
filePath = [filePath stringByAppendingString:fileName];
NSString *writeError = nil;
NSData * fileData = [NSPropertyListSerialization dataFromPropertyList:dataDic format:NSPropertyListXMLFormat_v1_0 errorDescription:&writeError];
if ([fileData writeToFile:filePath atomically:YES]) {
NSLog(#"Server file is stored locally");
}else {
NSLog(#"%#", writeError);
}
// store the file in iCloud folder
NSURL *ubiquitousURL = [[NSFileManager defaultManager] URLForUbiquityContainerIdentifier:nil];
NSString *tmpubiquitousURL = ubiquitousURL.absoluteString;
tmpubiquitousURL = [tmpubiquitousURL stringByAppendingString:fileName];
NSURL *ubi2 = [[NSURL alloc] initWithString:tmpubiquitousURL];
[[NSFileManager defaultManager] setUbiquitous:YES itemAtURL:filePathURL destinationURL:ubi2 error:&error];
I used the following to remove the file from iCloud but it gives an error that Cannot disable syncing on an un-synced file.
[[NSFileManager defaultManager] setUbiquitous:NO itemAtURL:filePathURL destinationURL:ubi2 error:&error];
I checked the availability of iCloud in my app delegate and it's available. The file is an XML file (.plist) and I have a local copy stored in NSDocumentDirectory.
Overall, I want to sync that file in iCloud so it will be accessible on all devices using my app. I have been struggling with this for 2 days, so if you could help me to resolve the problem I would appreciate it.
Note: I would rather not to use UIDocument, however, if that is the only option please let me know.
I also have the same problem while using the code
[[NSFileManager defaultManager] setUbiquitous:NO itemAtURL:filePathURL destinationURL:ubi2 error:&error];
you have to change the code like below for this to work correctly
[[[NSFileManager alloc]init]setUbiquitous:YES itemAtURL:filePathURL destinationURL:ubi2 error:nil];
this code is for moving a file to icloud, also you should change the name of the file you are moving. It should not be same.
my app need to download file, but I would like to store all those files into a rep in /var/mobile/Documents.
To create this folder I use :
NSString *path;
path = [#"/var/mobile/Documents/" stringByAppendingPathComponent:#"myFolder"];
NSError *error;
if (![[NSFileManager defaultManager] fileExistsAtPath:path]) //Does directory already exist?
{
if (![[NSFileManager defaultManager] createDirectoryAtPath:path
withIntermediateDirectories:NO
attributes:nil
error:&error])
{
NSLog(#"Create directory error: %#", error);
}
}
But it's don't work, can you tell me why ?
Thank
You shouldn't get the path to the documents folder that way. Use this instead:
NSString *dir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
path = [dir stringByAppendingPathComponent:#"myFolder"];
You shouldn't hard code system paths, except perhaps for /dev/null and /dev/random. Apple can change them at any time in a future iOS version.
BTW /var/mobile/Documents/ isn't writable anyway, because if it were it would interfere with other apps that also write there.
I seem to have stumbled over a problem regarding saving an xml file from a string (this is done on the iPhone)
The file itself exists and included in the project (hence within the workspace), and all indications I get from the code snippet which follows passes without any errors on the emulator and fail on the iPhone (error 513), but in either case the file is not saved!
{
Hits = config->Hits;
NSString* filenameStr = [m_FileName stringByAppendingFormat: #".xml" ];
NSString* pData = [self getDataString]; // write xml format - checked out ok
NSError *error;
/* option 2 - does not work as well
NSBundle *mainBundle = [NSBundle mainBundle];
NSURL *xmlURL = [NSURL fileURLWithPath:[mainBundle pathForResource: m_FileName ofType: #"xml"]];
if(![pData writeToURL: xmlURL atomically: true encoding:NSUTF8StringEncoding error:&error])
{
NSLog(#"Houston - we have a problem %s#\n",[error localizedFailureReason]);
return false;
}
*/
if(![pData writeToFile: filenameStr atomically: FALSE encoding:NSUTF8StringEncoding error:&error])
{
NSLog(#"Houston - we have a problem %s#\n",[error localizedFailureReason]);
return false;
}
return true;
}
Any help would be appreciated,
-A
You should not write to files included in the application package. On a real iPhone, you may be prevented from doing this because these files are digitally signed.
Even if you can modify a packaged file, it is not a good place to store data. Re-installing the application from an App Store upgrade or an Xcode build will overwrite the file with the original.
Instead, store your XML into the Documents directory. You can get the path like this:
NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,
NSUserDomainMask, YES);
NSString* documentsDirectory = [paths objectAtIndex:0];
NSString* leafname = [m_FileName stringByAppendingFormat: #".xml" ];
NSString* filenameStr = [documentsDirectory
stringByAppendingPathComponent:leafname];
If your file needs some initial state that you don't want to generate in your code, have your app check that it is present in the documents directory the first time it is needed and, if it is missing, copy it from the template in the package.
An alternative to storing structured data is to use user defaults. For example:
[[NSUserDefaults standardUserDefaults] setObject:foo forKey:FOO_KEY];