iOS UITextField Underline Style in swift - ios

Question

I've added this image, I hope you can see it, of a user interface login. Notice the text field is transparent with the exception of the line at the bottom. What code do I put in to get that affect? Can I put the necessary information in the "user defined runtime attributes"?

Answer 1

Create a subclass of UITextField as below, And simply set this class in your storyboard to UITextField
Swift 5 Support With #IBInspectable
import UIKit
class HSUnderLineTextField: UITextField , UITextFieldDelegate {
let border = CALayer()
#IBInspectable open var lineColor : UIColor = UIColor.black {
didSet{
border.borderColor = lineColor.cgColor
}
}
#IBInspectable open var selectedLineColor : UIColor = UIColor.black {
didSet{
}
}
#IBInspectable open var lineHeight : CGFloat = CGFloat(1.0) {
didSet{
border.frame = CGRect(x: 0, y: self.frame.size.height - lineHeight, width: self.frame.size.width, height: self.frame.size.height)
}
}
required init?(coder aDecoder: (NSCoder?)) {
super.init(coder: aDecoder!)
self.delegate=self;
border.borderColor = lineColor.cgColor
self.attributedPlaceholder = NSAttributedString(string: self.placeholder ?? "",
attributes: [NSAttributedString.Key.foregroundColor: UIColor.white])
border.frame = CGRect(x: 0, y: self.frame.size.height - lineHeight, width: self.frame.size.width, height: self.frame.size.height)
border.borderWidth = lineHeight
self.layer.addSublayer(border)
self.layer.masksToBounds = true
}
override func draw(_ rect: CGRect) {
border.frame = CGRect(x: 0, y: self.frame.size.height - lineHeight, width: self.frame.size.width, height: self.frame.size.height)
}
override func awakeFromNib() {
super.awakeFromNib()
border.frame = CGRect(x: 0, y: self.frame.size.height - lineHeight, width: self.frame.size.width, height: self.frame.size.height)
self.delegate = self
}
func textFieldDidBeginEditing(_ textField: UITextField) {
border.borderColor = selectedLineColor.cgColor
}
func textFieldDidEndEditing(_ textField: UITextField) {
border.borderColor = lineColor.cgColor
}
}
Set lineColor and selectedLineColor from the storyboard and run your project.