I am having random error while reading saved photos from document directory in iPhone. I save photos taken from my app to document directory and then read it from there next time when user come back. However, after XCode 6 & base SDK change to 8.1, this document directory path keeps changing. So sometime I found photos and sometime not.
I read few posts online thats says that not Apple differentiate App from Data and that's why this issue coming up. Anyone has any thoughts on this? Any solution?
This is how I save file to document Directory
NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDirectory = [path firstObject];
NSString *filePath = [documentDirectory stringByAppendingPathComponent:#"key"];
[image writeToFile:path atomically:YES];
And this is how I read it:
NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDirectory = [path firstObject];
NSString *filePath = [documentDirectory stringByAppendingPathComponent:#"key"];
UIImage *cellImage = [[UIImage alloc] initWithContentsOfFile:filePath];
Go to Product - Scheme - Edit Scheme - Options - Working Directory and specify working directory
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I am writing an app which downloads image from my server and stores them locally for offline viewing. The codes I use to store the image locally are shown below. Apart from storing the image, I am also able to read the image from the path (which I stored separately).
However when I re-run my code from Xcode to the iPhone (without uninstalling the app from the phone), the stored image file would be missing. Is this expected? Would I face similar issue when my app has been released on App Store and when the user updates the app? Is there a way to keep the file persistent when I re-run them when I update some codes in Xcode?
NSData *imageData = UIImageJPEGRepresentation(image, 1.0);
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *imagePath =[documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:#"file.jpeg",]];
if (![imageData writeToFile:imagePath atomically:YES])
{
// Handling when there is an error
NSLog(#"Failed to store file at path %#",imagePath);
stored.text = #"";
}
else
{ // Handling when write is successful
NSLog(#"Imaged stored path is %#",imagePath);
stored.text = imagePath;
}
[imageView setImage:image];
The code to read the image is shown below:
NSString *imagePathToRead = stored.text;
NSLog(#"Retrieve image from %#",imagePathToRead);
UIImage *image = [UIImage imageWithContentsOfFile:imagePathToRead];
[imageView setImage:image];
I am posting the answer here from rmaddy which solved the issue I was facing. I am posting here so that others can benefit if they are facing similar issue.
For the storing portion:
The stored.text should never store the full path:
stored.text = imagePath;
Instead I should store #"file.jpeg" only.
For the Read portion:
I should always regenerate the full path below when I wanted to read the path instead of the code below:
NSString *imagePathToRead = stored.text;
The corrected codes are:
NSString *imagePathToRead = stored.text;
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *imagePath =[documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:imagePathToRead]];
NSLog(#"Retrieve image from %#",imagePath);
UIImage *image = [UIImage imageWithContentsOfFile:imagePath];
This solved the issue and the image is able to be read even though the app is re-installed through Xcode.
On my iPhone app, I'm saving pictures associated with an event via this code:
[pngData writeToFile:filePath atomically:YES]; //Write the file
self.thisTransaction.picPath = filePath;
Later I retrieve and display the photo with this code:
UIImage * image = [UIImage imageWithContentsOfFile:thisTransaction.picPath];
Works great on my iPad (I don't have an iPhone).
However, if I update the app by connecting the iPad to my MB Pro after an Xcode code modification not involving the above lines, then disconnect and run it independently, the picture at the expected picPath is not retrieved. All other data associated with thisTransaction in Core Data is intact and unchanged, but the expected picture doesn't appear on the device after the update.
Can someone please tell me where I'm going wrong?
Edit to clarify file path construction
pngData = UIImagePNGRepresentation(capturedImage.scaledImage);
NSLog(#"1 The size of pngData should be %lu",(unsigned long)pngData.length);
//Save the image someplace, and add the path to this transaction's picPath attribute
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
int timestamp = [[NSDate date] timeIntervalSince1970];
NSString *timeTag = [NSString stringWithFormat:#"%d",timestamp];
filePath = [documentsPath stringByAppendingPathComponent:timeTag]; //Add the file name
NSLog(#"1 The picture was saved at %#",filePath);
The console log shows this filePath:
/Users/YoursTruly/Library/Developer/CoreSimulator/Devices/65FB33E1-03A7-430D-894D-0C1893E03120/data/Containers/Data/Application/EB9B9523-003E-4613-8C34-4E91B3357F5A/Documents/1433624434
The issue you are having is that the location of an app's sandbox can change over time. Typically this happens when an app is updated. So the worst thing you can do is persist absolute file paths.
What you need to do is persist just the part of the path relative to the base path (the "Documents" folder in this case).
Then when you want to reload the file again, append the persisted relative path to the current value of the "Documents" folder.
So your code needs to be something like this:
Save the file:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
int timestamp = [[NSDate date] timeIntervalSince1970];
NSString *timeTag = [NSString stringWithFormat:#"%d",timestamp];
filePath = [documentsPath stringByAppendingPathComponent:timeTag]; //Add the file name
[pngData writeToFile:filePath atomically:YES]; //Write the file
self.thisTransaction.picPath = timeTag; // not filePath
Load the file:
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsPath = [paths objectAtIndex:0]; //Get the docs directory
NSString *filePath = [documentsPath stringByAppendingPathComponent:thisTransaction.picPath];
UIImage *image = [UIImage imageWithContentsOfFile:filePath];
In an app I am working on I want to have an NSMutableArray (called pathsArray) that I can read from a file in the app's directory, be able create an instance of that array that I can add objects to and/or remove objects from, and then I want to write it back to the file. I have a UILabel that shows the number of contents in this array. My problem: my code below works fine on Xcode's iOS Simulator but when I try to run the app on my actual iPhone the data isn't saved. I know there are a lot of questions on here related to this issue but i can't seem to see what I am doing wrong. Any help would be greatly appreciated.
- (void) loadArrayContents {
NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString* documentsDirectory = [paths objectAtIndex:0];
NSString* filePath = [documentsDirectory stringByAppendingString:#"theArray"];
//Objects contained in an array returned by 'initWithContentsOfFile' are immutable even if the array is mutable
NSArray* contentsArray = [[NSMutableArray alloc] initWithContentsOfFile:filePath];
pathsArray = [[NSMutableArray alloc] initWithArray:contentsArray];
}
and...
- (void) saveArrayContents {
NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString* documentsDirectory = [paths objectAtIndex:0];
NSString* filePath = [documentsDirectory stringByAppendingString:#"theArray"];
[pathsArray writeToFile:filePath atomically:YES]);
}
NSString *filePath = [documentsDirectory stringByAppendingPathComponent:#"theArray"];
should solve the issue. The problem with
NSString *filePath = [documentsDirectory stringByAppendingString:#"theArray"];
is that it does not add / in the file path.
This was working for me yesterday morning and now it doesn't. So, I suspect something else changed to cause it...but I can't find the change. I've spent hours reverting my code back almost a week and still it's not working (and I know it was working yesterday morning). So, I'm hoping that in posting this specific issue (a symptom?) some ideas will surface that I can evaluate. Thanks.
I download images as they're needed:
NSFileManager *filemgr;
filemgr = [NSFileManager defaultManager];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDirectory = [paths objectAtIndex:0];
NSString *targetFile = [NSString stringWithFormat:#"%#/%#.%#", documentDirectory, imageName, imageType];
// only download those where an image exists
if(![imageType isEqualToString:#""])
{
// only download the file if there is not already a local copy.
if([filemgr fileExistsAtPath:targetFile] == NO)
{
NSMutableData *imageData = [[NSMutableData alloc] initWithLength:0];
[imageData appendData:data];
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *thumbNailFilename = [NSString stringWithFormat:#"%#.%#", imageName, imageType];
NSString *thumbNailAppFile = [documentsDirectory stringByAppendingPathComponent:thumbNailFilename];
}
}
Then display them:
NSString *imageFullName = [NSString stringWithFormat:#"%#%#", [greetingObject valueForKey:#"gid"], [greetingObject valueForKey:#"itp"]];
NSString *fullImagePath = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0] stringByAppendingPathComponent:imageFullName];
UIImage *greetingImage = [UIImage imageWithContentsOfFile:fullImagePath];
self.greetingImage.image = greetingImage;
The variables "imageFullName" and "fullImagePath" are populated with the correct data and the image files are present on the simulator in the specified directory. Yet, "greetingImage" equals nil.
Here's what I get for "fullImagePath": /Users/Steve2/Library/Application Support/iPhone Simulator/7.1/Applications/8C9F8417-F6E2-4B38-92B3-82A88477CB7F/Documents/165.jpg
Here are the image files:
I have also tried variations using initWithContentsOfFile and dataWithContentsOfFile and get the same result. The greetingImage variable is nil.
I appreciate your ideas. I've even reinstalled Xcode in hopes that something got corrupted. No dice.
Added: One thing I just thought of... I did add the SystemConfiguration.framework to the project yesterday for an unrelated feature. It's currently at the top of the Linked Frameworks and Libraries list. I have no experience working with this. Could it be causing the problem?
Thanks.
Your code looks correct.
I would check that the images themselves are still okay. Looking at the screenshot you posted Finder isn't showing previews of the images which it should do with a valid JPEG. You say that the images are being downloaded so I suspect that they are being corrupted somehow on the way down.
EDIT:
Didn't notice that you were using initWithContentsOfFile. Since you are saving the files as NSData objects you will need to load them into memory as NSData objects and then init a UIImage with the data object, like so:
NSData *imageData = [NSData dataWithContentsOfFile:filePath];
[UIImage imageWithData:imageData];
I have created some PDF files programatically, which i am storing into the devices memory using the following code >>>>
NSString *fileName = [NSString stringWithFormat:#"SampleTextFile.pdf",strFinalString];
NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *saveDirectory = [path objectAtIndex:0];
NSString *saveFileName = fileName;
NSString *documentPath = [saveDirectory stringByAppendingPathComponent:saveFileName];
I can see the file in the Devices Document folder.
I want to hide these files so that the user can not see or delete it.
Can anyone help me out to do this.
A good place to store private data is in ~/Library/Application Support/, which is the folder used on the Mac for this purpose.
You can generate a path to this folder using:
NSString *appSupportDir = [NSSearchPathForDirectoriesInDomains(NSApplicationSupportDirectory, NSUserDomainMask, YES) firstObject];
You'll have to create the folder yourself the first time you use it, which you can do with:
if (![[NSFileManager defaultManager] fileExistsAtPath:appSupportDir])
{
[[NSFileManager defaultManager] createDirectoryAtPath:appSupportDir withIntermediateDirectories:YES attributes:nil error:NULL];
}
I wrote a simple library that makes this and all other useful iOS folders available as methods on NSFileManager: https://github.com/nicklockwood/StandardPaths
Just prefix the filename with a dot, as in .SampleTextFile.pdf.
But the real solution is to not store the document in the NSDocumentDirectory in the first place. You should create subdirectory in the NSLibraryDirectory and store this stuff there. It also gets backed up and will not get purged like Caches and tmp, but the user cannot access it with iTunes.