How to count the number of glyphs in NSLayoutManager

Question

How do I get the total number of glyphs that are in NSLayoutManager?

I was making a cursor layer to overlay on a custom text view like this:

func moveCursorToGlyphIndex(glyphIndex: Int) {

    // get bounding rect for glyph
    var rect = self.layoutManager.boundingRectForGlyphRange(NSRange(location: glyphIndex, length: 1), inTextContainer: view.textContainer)
    rect.origin.y = self.textContainerInset.top
    rect.size.width = cursorWidth

    // set cursor layer frame to right edge of rect
    cursorLayer.frame = rect
}

However, I wanted to make sure that glyphIndex is not out of bounds. Something like this:

if glyphIndex < self.layoutManager.glyphCount { // doesn't work
    // ...
}

I couldn't find the right property by trial and error, though, and searching online didn't show any SO answers.

I finally did find it in buried in the documentation (and now it seems obvious), but since it took a long time, I decided I would add a Q&A here.

Answer 1

Use the numberOfGlyphs property, as in

layoutManager.numberOfGlyphs

This is demonstrated in the Text Layout Programming Guide documentation here.