Counting the number of lines in a UITextView, lines wrapped by frame size

Question

I wanted to know when a text is wrapped by the frame of the text view is there any delimiter with which we can identify whether the text is wrapped or not.

For insta

Answer 1

I spent a lot of time trying to calculate in real time the number of lines for an input TextView (say a chat text entry box) and the only solution that works in such a case is Luke Chase's (for some reason the frame.height approach appears to update only ever 3rd or fourth letter typed into a textView and so is not accurate).

As a commenter mentioned however, there is a small bug in which a user generated line breaks ("\n" or keyboard return press) are not properly accounted for. Even stranger, it only "misses" the first such line-break, any subsequent ones are correctly captured (say you go to the line 4 times it will return only 3 lines clearly missing the first line break).

So to go around that bug I simple look record the first such line-break (character "\n") and manually add a line to the # of lines that the gliph method returns.

In code that gives:

    func offSetTableViewIfNeeded() {
    let numberOfGlyphs = textView.layoutManager.numberOfGlyphs
    var index : Int = 0
    var lineRange = NSRange(location: NSNotFound, length: 0)
    var currentNumOfLines : Int = 0
    var numberOfParagraphJump : Int = 0

    while index < numberOfGlyphs {
        textView.layoutManager.lineFragmentRect(forGlyphAt: index, effectiveRange: &lineRange)
        index = NSMaxRange(lineRange)
        currentNumOfLines += 1

        // Observing whether user went to line and if it's the first such line break, accounting for it.
        if textView.text.last == "\n", numberOfParagraphJump == 0 {
            numberOfParagraphJump = 1
        }
    }

    currentNumOfLines += numberOfParagraphJump

    print("Number of lines is:", currentNumOfLines)

Hope this helps others who've been struggling with the super weird behavior of input textView (can't understand why Apple does not provide a # of line method out of the box!).