webViewDidFinishLoad not firing called working - xcode

Question

(Swift, iOS8, Xcode6, iPhone/iPad)
webViewDidFinishLoad is not being called, is not firing, and is not working.
Yes, I have set the containing view controller as the delegate. I CTRL-mousedowned on the UIWebView, dragged up to the little yellow circle representing the view controller, and released. A right-click on the UIWebView object shows that the delegate is set.
Yes, I did implement UIWebViewDelegate in my class declaration, like so:
class Paragraph: UIViewController, UIWebViewDelegate {
Yes, I did restart Xcode, and test on both the simulator and an actual iPhone 4S.
The request looks like this:
#IBOutlet var paragraph : UIWebView = nil
var r = NSBundle.mainBundle().pathForResource("cheddar", ofType: "htm")
var u = NSURL(fileURLWithPath: r)
paragraph.loadRequest(NSURLRequest(URL: u))
The callback function looks like this:
func webViewDidFinishLoad() {
println("webViewDidFinishLoad")
}

Answer 1

I got it. The callback was missing a parameter. For posterity:
func webViewDidFinishLoad(webView: UIWebView!) {
Note the webView: UIWebView! parameter
In this case, perhaps even more important, is the way I found the bug. I created an entirely new view controller, and pieced it back together, carefully checking at each step to make sure that I didn't miss anything.
When the Intellisense popup showed the function with the parameter, I saw my error.
NOTE: In Swift 2.2, the UIWebViewDelegate protocol specifies a different optionality:
webView: UIWebView.
webView: UIWebView! spawns a warning.