show custom fonts family names

gistfile1.m

  for(NSString *fontfamilyname in [UIFont familyNames])
  {
    if (![fontfamilyname containsString:@"elvetica"]) {
      continue;
    }
      NSLog(@"family:'%@'",fontfamilyname);
      for(NSString *fontName in [UIFont fontNamesForFamilyName:fontfamilyname])
      {
          NSLog(@"\tfont:'%@'",fontName);
      }
      NSLog(@"-------------");
  }

gistfile2.swift

    for family: String in UIFont.familyNames()
    {
       print("\(family)")
       for names: String in UIFont.fontNamesForFamilyName(family)
       {
           print("== \(names)")
       }
    }