Downloading From Parse on Apple TV

Question

I have a parse server set up, and as part of it, small PDFs (425KB) are stored on it. I need my Apple TV to be able to display these, but since they change often, it has to come from Parse server, and not just the main bundle where I update it with each update of the app. The issue I'm running into is the lack of an NSDocumentsDirectory on the Apple TV. How do y'all handle this? I've been using the Cache directory, but it seems to only work half the time with the code I am currently using. If I run it at launch from AppDelegate, by the time the PDF is needed, it may not be there, and if I have it set to run this code right when I need it, there is a delay, and sometimes, it simply doesn't show up. Would using NSTemporaryDirectory() be better? UPDATE, no, it doesn't. Works fine on simulator, on Apple TV, have to run the code two times to get it to both download, and draw the PDF

-(void)sermonTime {
    //Check if PFFile exists, if so, display PDF, if not, blank time.
    if ([self.entry[@"SermonPresIncluded"] isEqualToString:@"NO"]) {
        [self blankTime];
    }
    else {
        NSLog(@"SermonTime");
        PFFileObject *thumbnail = self.entry[@"SermonPDF"];
       
        [thumbnail getDataInBackgroundWithBlock:^(NSData *imageData, NSError *error) {
            NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
            NSString *documentsDirectory = [paths objectAtIndex:0];
            NSString *pdfPath = [[documentsDirectory stringByAppendingPathComponent:[self.entry valueForKey:@"DateOfService"]] stringByAppendingString:@".pdf"];
            
            [imageData writeToFile:pdfPath atomically:YES];
            
            
            NSURL *url = [NSURL fileURLWithPath:pdfPath];
            self.view.backgroundColor = [UIColor blackColor];
            self.arrayOfVerses = @[@"allverses"];
            CGPDFDocumentRef pdfDocument = [self openPDF:url];
            [self drawDocument:pdfDocument];

        }];
    }
      
}

Answer 1

-(void)sermonTime {
    // Check if PFFile exists, if so, display PDF, if not, blank time.
    if ([self.entry[@"SermonPresIncluded"] isEqualToString:@"NO"]) {
        [self blankTime];
    }
    else {
        NSLog(@"SermonTime");
        PFFileObject *thumbnail = self.entry[@"SermonPDF"];

        NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
        NSString *documentsDirectory = [paths objectAtIndex:0];
        NSString *pdfPath = [[documentsDirectory stringByAppendingPathComponent:[self.entry valueForKey:@"DateOfService"]] stringByAppendingString:@".pdf"];

        NSFileManager *fileManager = [NSFileManager defaultManager];

        if ([fileManager fileExistsAtPath:pdfPath]) {
            // Use cached copy of PDF
            NSURL *url = [NSURL fileURLWithPath:pdfPath];
            self.view.backgroundColor = [UIColor blackColor];
            self.arrayOfVerses = @[@"allverses"];
            CGPDFDocumentRef pdfDocument = [self openPDF:url];
            [self drawDocument:pdfDocument];
        } else {
            // Download and save the PDF
            [thumbnail getDataInBackgroundWithBlock:^(NSData *imageData, NSError *error) {
                if (error) {
                    // Handle the error
                    NSLog(@"Error downloading PDF: %@", error);
                    [self blankTime];
                } else {
                    [imageData writeToFile:pdfPath atomically:YES];

                    // Use completion block to signal that the PDF is ready to display
                    dispatch_async(dispatch_get_main_queue(), ^{
                        NSURL *url = [NSURL fileURLWithPath:pdfPath];
                        self.view.backgroundColor = [UIColor blackColor];
                        self.arrayOfVerses = @[@"allverses"];
                        CGPDFDocumentRef pdfDocument = [self openPDF:url];
                        [self drawDocument:pdfDocument];
                    });
                }
            }];
        }
    }
}

Made some changes to the code.

It will first check if the PDF exists cache, it will use the PDF if it exists in cache and will only proceed download if it does not exists. Then, to make sure that PDF is downloaded and saved successfully you can use a completion block. With completion block, it will only proceed to draw it when the block is called to avoid the PDF does't show up.

Answer 2

I think you have problems because of the cache. A solution could be to clear the cache whenever a new PDF becomes available. You can do this by deleting the cached PDF file before downloading the new one.

LE: Here's a revised version that uses writeToFile:atomically: and then calls the completion block

- (void)sermonTime {
if ([self.entry[@"SermonPresIncluded"] isEqualToString:@"NO"]) {
    [self blankTime];
}
else {
    NSLog(@"SermonTime");
    PFFileObject *thumbnail = self.entry[@"SermonPDF"];

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0];
    NSString *pdfPath = [[documentsDirectory stringByAppendingPathComponent:[self.entry valueForKey:@"DateOfService"]] stringByAppendingString:@".pdf"];

    NSFileManager *fileManager = [NSFileManager defaultManager];

    if ([fileManager fileExistsAtPath:pdfPath]) {
        // Use cached copy of PDF
        NSURL *url = [NSURL fileURLWithPath:pdfPath];
        self.view.backgroundColor = [UIColor blackColor];
        self.arrayOfVerses = @[@"allverses"];
        CGPDFDocumentRef pdfDocument = [self openPDF:url];
        [self drawDocument:pdfDocument];
    } else {
        // Delete the cached PDF file before downloading the new one
        [fileManager removeItemAtPath:pdfPath error:nil];

        // Download and save the PDF
        [thumbnail getDataInBackgroundWithBlock:^(NSData *imageData, NSError *error) {
            if (error) {
                NSLog(@"Error downloading PDF: %@", error);
                [self blankTime];
            } else {
                [imageData writeToFile:pdfPath atomically:YES];

                // Use completion block to signal that the PDF is ready to display
                dispatch_async(dispatch_get_main_queue(), ^{
                    NSURL *url = [NSURL fileURLWithPath:pdfPath];
                    self.view.backgroundColor = [UIColor blackColor];
                    self.arrayOfVerses = @[@"allverses"];
                    CGPDFDocumentRef pdfDocument = [self openPDF:url];
                    [self drawDocument:pdfDocument];
                });
            }
        }];
    }
}
}