Changing UITextField Placeholder font

Objective-C:

UIColor *color = [UIColor blackColor];    
someUITextField.attributedPlaceholder =
  [[NSAttributedString alloc] initWithString:@"Placeholder Text"
    attributes:@{
       NSForegroundColorAttributeName: color,
       NSFontAttributeName : [UIFont fontWithName:@"Roboto-Bold" size:17.0]
    }
  ];

(There are no brackets between literal dictionary key-value pairs.)

Swift:

let attributes = [
    NSForegroundColorAttributeName: UIColor.blackColor(),
    NSFontAttributeName : UIFont(name: "Roboto-Bold", size: 17)! // Note the !
]

someUITextField.attributedPlaceholder = NSAttributedString(string: "Placeholder Text", attributes:attributes)