How to place a question mark button in a NSAlert that opens an online web page?
macos, nsalert
Solution
You should make your controller class conform to `NSAlertDelegate`. Then, set `myAlert.delegate = self` and `myAlert.showsHelp = true`. In your controller class, implement `func alertShowHelp(_ alert: NSAlert) -> Bool` to do whatever you like.
In general, to open URLs in the user's default browser, use `NSWorkspace` and its `open()` method.
Problem
EDIT: My question was not very clear now I edited it to make it clear that I need to open an online web page and not the help book. I would like to include a question mark button in a NSAlert in a macOS project that points to an online web page with the help resource. I saw here that there are two possibilities: var showsHelp: Bool Specifies whether the alert has a help button. var helpAnchor: String? The alert’s HTML help anchor. But I can't figure out how to implement it. I use this code: ``` @IBAction func buttonPressed(_ sender: Any) { let myAlert: NSAlert = NSAlert() myAlert.messageText = "Message" myAlert.informativeText = "Informative text." myAlert.showsSuppressionButton = true myAlert.addButton(withTitle: "Later") myAlert.addButton(withTitle: "Now") myAlert.addButton(withTitle: "OK") let choice = myAlert.runModal() switch choice { case NSAlertFirstButtonReturn: print ("OK") case NSAlertSecondButtonReturn: print ("Now") case NSAlertThirdButtonReturn: print ("Later") default: break } if myAlert.suppressionButton!.state == 1 { print ("Checked") } else { print ("Not checked") } } ```