How to check if text is underlined - swift

Question

I am struggling to determine if some selected text in a UITextView is underlined. I can quite easily check for bold, italics etc with the following code:
let isItalic = textView.font!.fontDescriptor.symbolicTraits.contains(.traitItalic)
However, I can't figure out how to check for underline?

Answer 1

I have just created a sample project and I think you could do something like the following:
class ViewController: UIViewController {
#IBOutlet weak var textView: UITextView!
override func viewDidLoad() {
super.viewDidLoad()
let attrText1 = NSMutableAttributedString(string: "TestTest", attributes: [.foregroundColor : UIColor.systemTeal, .underlineStyle: NSUnderlineStyle.single.rawValue])
let attrText2 = NSAttributedString(string: " - not underlined", attributes: [.foregroundColor : UIColor.red])
attrText1.append(attrText2)
textView.attributedText = attrText1
}
func isTextUnderlined(attrText: NSAttributedString?, in range: NSRange) -> Bool {
guard let attrText = attrText else { return false }
var isUnderlined = false
attrText.enumerateAttributes(in: range, options: []) { (dict, range, value) in
if dict.keys.contains(.underlineStyle) {
isUnderlined = true
}
}
return isUnderlined
}
#IBAction func checkButtonDidTap(_ sender: UIButton) {
print(isTextUnderlined(attrText: textView.attributedText, in: textView.selectedRange))
}
}
Create an extension to get the selectedRange as NSRange:
extension UITextInput {
var selectedRange: NSRange? {
guard let range = selectedTextRange else { return nil }
let location = offset(from: beginningOfDocument, to: range.start)
let length = offset(from: range.start, to: range.end)
return NSRange(location: location, length: length)
}
}

Answer 2

I believe underline is not part of the font traits, it must rather be an attribute to the text. You might find the answer to this question useful. I hope it helps you! Enumerate over a Mutable Attributed String (Underline Button)

Answer 3

func checkForUnderline(){
let allWords = self.testView.text.split(separator: " ")
for word in allWords {
let result = self.isLabelFontUnderlined(textView: self.testView,
subString: word as NSString)
if(result == true){
print(word+" is underlined")
}else{
print(word+" is not underlined")
}
}
}
func isLabelFontUnderlined (textView: UITextView, subString:
NSString) -> Bool {
let nsRange = NSString(string: textView.text).range(of: subString as
String, options: String.CompareOptions.caseInsensitive)
if nsRange.location != NSNotFound {
return self.isLabelFontUnderlined(textView: textView,
forRange: nsRange)
}
return false
}
func isLabelFontUnderlined (textView: UITextView, forRange: NSRange) ->
Bool{
let attributedText = testView.attributedText!
var isRangeUnderline = false
attributedText.enumerateAttributes(in: forRange,
options:.longestEffectiveRangeNotRequired) { (dict, range, value) in
if dict.keys.contains(.underlineStyle) {
if (dict[.underlineStyle] as! Int == 1){
isRangeUnderline = true
} else{
isRangeUnderline = false
}
}else{
isRangeUnderline = false
}
}
return isRangeUnderline
}