The link below is a widely-referenced technique for putting hyperlinks into Cocoa apps. However, there are two glitches to this technique. 1) the cursor is an I-beam instead of an arrow. The fix for that glitch is painful and discussed in many blogs. 2) the font changes to the system default when you click the link. This problem is very easy to fix, but I didn’t see anyone else documenting the solution.
The fix is as follows: apply the label’s font to the attributed text.
[attString addAttribute:NSFontAttributeName value:[label font] range:NSMakeRange(0, [attString length])];
https://developer.apple.com/library/mac/qa/qa1487/_index.html