Multiline attributed string with strikethrough - ios

Question

I have a label with:
label.numberOfLines = 0
And I'm trying to make text of this label strikethrough with:
let index: NSMutableAttributedString = NSMutableAttributedString(string: label.text!)
index.addAttributes([NSStrikethroughStyleAttributeName: NSUnderlineStyle.styleSingle.rawValue, NSStrikethroughColorAttributeName: UIColor.red], range: NSMakeRange(0, index.length))
label.textColor = UIColor.red
label.attributedText = index
Is it true that attributed string is not working with multilines or with labels with numberOfLines set to 0? And if so, how to make multiline text strikethrough?

Answer 1

Works fine with multiline if you add NSBaselineOffsetAttributeName before:
let attributeString: NSMutableAttributedString = NSMutableAttributedString(string: (object?.title)!)
attributeString.addAttribute(NSBaselineOffsetAttributeName, value: 0, range: NSMakeRange(0, attributeString.length))
attributeString.addAttribute(NSStrikethroughStyleAttributeName, value: 2, range: NSMakeRange(0, attributeString.length))

Answer 2

Your code should be like,
let index: NSMutableAttributedString = NSMutableAttributedString(string: lbl.text!)
index.addAttributes([NSStrikethroughStyleAttributeName: NSUnderlineStyle.styleSingle.rawValue, NSStrikethroughColorAttributeName: UIColor.red], range: NSMakeRange(0, index.length))
lbl.textColor = UIColor.red
lbl.attributedText = index
because index is your mutable string! not title!
And you can not use strike through with multi line label.
If you want strike through effect in multiple lines then you can use UITextView instead of label!

Answer 3

Write it like,
self.label.numberOfLines = 0
let attributeString: NSMutableAttributedString = NSMutableAttributedString(string: self.label.text!)
attributeString.addAttribute(NSStrikethroughStyleAttributeName, value: 1, range: NSMakeRange(0, attributeString.length))
self.label.attributedText = attributeString
Working at my end.

Answer 4

I came up with two solutions. They are based on #SivajeeBattina answer.
First one is to strike out text with help of http://adamvarga.com/strike/.
private func returnStrikedOutTextFromString(_ str: String) -> String {
var newString = ""
let normal = "АБВГДЕЁЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯабвгдеёжзийклмнопрстуфхцчшщъыьэюя "
let strikethrough = "А̶Б̶В̶Г̶Д̶Е̶Ё̶Ж̶З̶И̶Й̶К̶Л̶М̶Н̶О̶П̶Р̶С̶Т̶У̶Ф̶Х̶Ц̶Ч̶Ш̶Щ̶Ъ̶Ы̶Ь̶Э̶Ю̶Я̶а̶б̶в̶г̶д̶е̶ё̶ж̶з̶и̶й̶к̶л̶м̶н̶о̶п̶р̶с̶т̶у̶ф̶х̶ц̶ч̶ш̶щ̶ъ̶ы̶ь̶э̶ю̶я̶ ̶̶"
for i in 0..<str.characters.count {
let range: Range<String.Index> =
normal.range(of: str
.substring(to: str.index(str.startIndex, offsetBy: i + 1))
.substring(from: str.index(str.startIndex, offsetBy: i)))!
let index: Int = normal.distance(from: normal.startIndex, to: range.lowerBound)
newString = String(format: "%#%#", newString,
NSLocalizedString(strikethrough
.substring(to: strikethrough.index(strikethrough.startIndex, offsetBy: index + 1))
.substring(from: strikethrough.index(strikethrough.startIndex, offsetBy: index)),
comment: ""))
}
return newString
}
And second one is: https://github.com/GuntisTreulands/UnderLineLabel