How can I check the spelling of a NSTextField using swift? I'm already using controlTextDidChange to validate the text. This solution seems to mention casting the first responder as a NSTextView but I'm not sure that is possible with swift using coercion. I know this would be easier if I changed to a NSTextView but if possible I'd like to avoid this.
This should help you out.
// Focus TextField
phraseTextField.becomeFirstResponder()
// Enable Continous Spelling
let textView: NSTextView = (self.window!.firstResponder as! NSTextView)
textView.continuousSpellCheckingEnabled = true
Adapted from: How do I enable spell checking within an NSTextField on Mac OS X?
In other situations, it may just work better to change NSTextFields to NSTextViews. Simply use a "Text View" (search NSTextView in the Object Library) and spell check will be on by default. NSTextFields simply do not support spell check in some cases, as best I can tell.