The initializers expect named arguments.
extension UIFont {
func sizeOfString (string: String, constrainedToWidth width: Double) -> CGSize {
return NSString(string: string).boundingRectWithSize(CGSize(width: width, height: DBL_MAX),
options: NSStringDrawingOptions.UsesLineFragmentOrigin,
attributes: [NSFontAttributeName: self],
context: nil).size
}
}
Note: String
s can be cast to NSString
s.
extension UIFont {
func sizeOfString (string: String, constrainedToWidth width: Double) -> CGSize {
return (string as NSString).boundingRectWithSize(CGSize(width: width, height: DBL_MAX),
options: NSStringDrawingOptions.UsesLineFragmentOrigin,
attributes: [NSFontAttributeName: self],
context: nil).size
}
}
or
extension UIFont {
func sizeOfString (string: NSString, constrainedToWidth width: Double) -> CGSize {
return string.boundingRectWithSize(CGSize(width: width, height: DBL_MAX),
options: NSStringDrawingOptions.UsesLineFragmentOrigin,
attributes: [NSFontAttributeName: self],
context: nil).size
}
}
--
UPDATED
For Swift 4 syntax
extension UIFont {
func sizeOfString (string: String, constrainedToWidth width: Double) -> CGSize {
return NSString(string: string).boundingRect(
with: CGSize(width: width, height: .greatestFiniteMagnitude),
options: .usesLineFragmentOrigin,
attributes: [.font: self],
context: nil).size
}
}