Is there any reason why writing and saving a PDF file to the Documents directory in an iOS application would only be intermittently successful? In my app I am created a PDF from an array of UIViews, accessing the Documents folder and storing the file in there.
I would estimate that this works 80% of the time. The other 20% of the time the PDF gets created (I also email it to myself which works) but it never actually get written to the Documents folder.
In the case of failure, I can email myself the PDF so I know it gets created. When I inspect the Documents folder in a file explorer it's empty. When I log out the contents of it it is also empty. I'm using the following code to create the PDF and export to Documents.
- (NSURL *)applicationDocumentsDirectory
{
return [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] lastObject];
}
-(void)createPDFfromUIViews:(NSArray *)views saveToDocumentsWithFileName:(NSString*)aFilename andTag:(NSInteger)tag
{
// Creates a mutable data object for updating with binary data, like a byte array
NSMutableData *pdfData = [NSMutableData data];
// Points the pdf converter to the mutable data object and to the UIView to be converted
UIView *view1 = [views objectAtIndex:0];
UIGraphicsBeginPDFContextToData(pdfData, view1.bounds, nil);
CGContextRef pdfContext = UIGraphicsGetCurrentContext();
// draws rect to the view and thus this is captured by UIGraphicsBeginPDFContextToData
for (UIView *view in views)
{
UIGraphicsBeginPDFPage();
[view.layer renderInContext:pdfContext];
}
// remove PDF rendering context
UIGraphicsEndPDFContext();
// Get the path to the documents directory and append the filename of the PDF
NSString *path = [[self applicationDocumentsDirectory].path stringByAppendingPathComponent:aFilename];
NSLog (@"DOCUMENTS DIRECTORY : %@", [self applicationDocumentsDirectory].path);
NSLog (@"DOCUMENTS DIRECTORY WITH FILE PATH : %@", path);
NSError *error = nil;
BOOL success = [pdfData writeToFile:path options:NSDataWritingWithoutOverwriting error:&error];
if (!success)
{
NSLog(@"Error writing PDF: %@", [error localizedDescription]);
}
else
{
if (tag == 1)
{
NSLog(@"PDF Saved With Name %@", aFilename);
[self.navigationController popViewControllerAnimated:YES];
}
else if (tag == 2)
{
[self checkAccountAndComposeEmailWithAttachmentData:pdfData andSubject:aFilename];
}
}
}
UPDATE: Code amended to include NSError. The error given is "The operation couldnt be completed. (Cocoa Error 4.)
UPDATE 2: Amended the code to include Apple's recommended method of grabbing the Documents directory. Also added in a number of logs to show that I am getting correct Directory / File Path - both are showing the Documents folder or the Documents/File Name as expected. Still returns NSFileNoSuchFileError
as an error every time.
You probably should be writing with the API that allows you to pass an error pointer in
- (BOOL)writeToFile:(NSString *)path options:(NSDataWritingOptions)mask error:(NSError **)errorPtr
Then, you can inspect the NSError
if it does not write properly, and act intelligently with this info.
NSError *error = nil;
BOOL success = [pdfData writeToFile:documentDirectoryFilename options:NSDataWritingAtomic error:&error];
if (!success) {
NSLog(@"Error writing: %@", [error localizedDescription]);
}
The specific error you have is a NSFileNoSuchFileError , a clue that perhaps there are spaces or some other non-supported character in the file path, amongst other reasons.
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