Add subtitle under the title in navigation bar controller in Xcode
original source: https://stackoverflow.com/questions/38626004/add-subtitle-under-the-title-in-navigation-bar-controller-in-xcode
Though there is a solution but it has some known issues
Solution is writing a function like this
func setTitle(title:String, subtitle:String) -> UIView {
let titleLabel = UILabel(frame: CGRectMake(0, -2, 0, 0))
titleLabel.backgroundColor = UIColor.clearColor()
titleLabel.textColor = UIColor.grayColor()
titleLabel.font = UIFont.boldSystemFontOfSize(17)
titleLabel.text = title
titleLabel.sizeToFit()
let subtitleLabel = UILabel(frame: CGRectMake(0, 18, 0, 0))
subtitleLabel.backgroundColor = UIColor.clearColor()
subtitleLabel.textColor = UIColor.blackColor()
subtitleLabel.font = UIFont.systemFontOfSize(12)
subtitleLabel.text = subtitle
subtitleLabel.sizeToFit()
let titleView = UIView(frame: CGRectMake(0, 0, max(titleLabel.frame.size.width, subtitleLabel.frame.size.width), 30))
titleView.addSubview(titleLabel)
titleView.addSubview(subtitleLabel)
let widthDiff = subtitleLabel.frame.size.width - titleLabel.frame.size.width
if widthDiff < 0 {
let newX = widthDiff / 2
subtitleLabel.frame.origin.x = abs(newX)
} else {
let newX = widthDiff / 2
titleLabel.frame.origin.x = newX
}
return titleView
}
Using this function for custom navigation title view in viewDidLoad
self.navigationItem.titleView = setTitle("Title", subtitle: "SubTitle")
Only known issue is that if subtitle becomes very large than the misplacement occurs.

Source: https://gist.github.com/nazywamsiepawel/0166e8a71d74e96c7898