如何在COCOA（MAC OS X）中添加PDF附件？

Question

我是MacOSx创建PDF的新手。 我完成了使用以下代码从OS X创建PDF。

NSPrintInfo *printInfo;
NSPrintInfo *sharedInfo;
NSPrintOperation *printOp;
NSMutableDictionary *printInfoDict;
NSMutableDictionary *sharedDict;
sharedInfo = [NSPrintInfo sharedPrintInfo];
sharedDict = [sharedInfo dictionary];
printInfoDict = [NSMutableDictionary 
dictionaryWithDictionary:sharedDict];
[printInfoDict setObject:NSPrintSaveJob forKey:NSPrintJobDisposition];
NSString *tempFileName = 
[NSString stringWithFormat:@"%@_file_%lu.pdf", 
[[NSProcessInfo processInfo] globallyUniqueString], fileNumber];
NSURL *poTempfileURL = 
[_tempDirectoryURL URLByAppendingPathComponent:tempFileName];
[printInfoDict setObject:poTempfileURL forKey:NSPrintJobSavingURL];
printInfo = 
[[NSPrintInfo alloc] initWithDictionary:printInfoDict];//1
[printInfo setHorizontalPagination: NSAutoPagination];//2
[printInfo setVerticalPagination: NSAutoPagination];//3
[printInfo setVerticallyCentered:NO];//4

printOp = [NSPrintOperation printOperationWithView:textView    printInfo:printInfo];//5
[printOp setShowsPrintPanel:NO];
[printOp setShowsProgressPanel:NO];//6
DLog(@"poTempfileURL=%@",poTempfileURL);

BOOL didRunOK = [printOp runOperation];//7

现在我只想在PDF中添加文件作为附件。

请帮帮我。