UIDocumentInteractionController showing file name and file type , not file contents

Question

I have NSData , which i saved in a folder inside document directory with .pdf file extension & when I try to open it using UIDocumentInteractionController it is showing me only file name & type, not the content. I checked in document directory folder for simulator & a .pdf file exists there.

//Saving NSData
+ (NSString *)createTempDocumentDirectory:(NSString *)dirName
                         andStoreData:(NSData *)data
                         withFileName:(NSString *)name
                     andFileExtension:(NSString *)extension
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *documentsDirectory = [paths objectAtIndex:0]; // Fetch path for document directory
    NSMutableString *dirPath = (NSMutableString *)[documentsDirectory stringByAppendingPathComponent:dirName];
    NSString *fileName = [NSString stringWithFormat:@"%@.%@", name, extension];
    NSString *path = [dirPath stringByAppendingPathComponent:fileName];

    return path;
}                         //Presenting contents of view

- (void)loadDocumentPreview:(NSURL *)fileURL
{    
    if (fileURL)
    {
        self.documentInteractionController = [UIDocumentInteractionController interactionControllerWithURL:[self fileURLDocumentPath:documentPath]];
        self.documentInteractionController.name = @"";
        [self.documentInteractionController setDelegate:self];
        [self.documentInteractionController presentPreviewAnimated:YES];
    }
}