如何通过“ didSelectRowAtIndexPath”使用我的应用程序文档目录中的文件？

NSArray *songs;
AVAudioPlayer *player;

- (void)viewDidLoad
{
  [self.player prepareToPlay];

  // Point to Document directory
  NSString *path = [NSHomeDirectory() stringByAppendingPathComponent:@\"Documents\"];
  NSError *error = nil;
  NSArray *array = [[NSFileManager defaultManager] contentsOfDirectoryAtPath:path error:&error];

  if (array == nil) {
    // Handle the error
  }
  self.songs = array;
  //[array release];

  //self.title = @\"Song List\";
  [super viewDidLoad];
  // Do any additional setup after loading the view from its nib.
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
  NSString *applicationDocumentsDirectory = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
  NSString *filePath = [applicationDocumentsDirectory stringByAppendingPathComponent: [songs objectAtIndex:indexPath.row]];
  NSURL *url = [NSURL fileURLWithPath:filePath];

  player = [[AVAudioPlayer alloc]initWithContentsOfURL:url error:nil];

  [player play];
}