Can't print a folder of PDF files

Question

I'd like to allow a user to print a folder of PDFs (pdfList array). I can't seem to get the code below to work. I keep getting the errow message below. I'm new to coding, and trying to modify some existing code. I get the sense of the error. I need to provide more information about the PDF, but don't know what to do. Suggestions?

Error:

ERROR: attempting to display print options with no printing source (item/items/formatter/renderer) set

- (IBAction)printAllPDFs:(id)sender {

    Class printControllerClass = NSClassFromString(@"UIPrintInteractionController");
    if (printControllerClass) {
        printController = [printControllerClass sharedPrintController];}

    NSFileManager *fileManager = [[NSFileManager alloc] init];

    for(int i = 0; i < _pdfList.count; i++){
        printController.delegate = self;
        UIPrintInfo *printInfo = [UIPrintInfo printInfo];
        printInfo.outputType = UIPrintInfoOutputGeneral;
        printInfo.jobName = [_pdfList[i] lastPathComponent];
        printInfo.duplex = UIPrintInfoDuplexLongEdge;
        printController.printInfo = printInfo;
        printController.showsPageRange = YES;
        printController.printingItem = [fileManager contentsOfDirectoryAtPath:_pdfList[i] error:nil];

        void (^completionHandler)(UIPrintInteractionController *, BOOL, NSError *) = ^(UIPrintInteractionController *printController, BOOL completed, NSError *error) {
            if (!completed && error) {
                NSLog(@"FAILED! due to error in domain %@ with error code %u", error.domain, error.code);
            }
        };

        [printController presentAnimated:YES completionHandler:completionHandler];
    }
}