How to hide "Welcome Back" banner from Game Center login?

Question

I've been looking for this information through Apple documents, but could not find the answer. Soon after I launch my Game Center app there is a pop-up that says:

Welcome back, PlayerName

How can I hide the "Welcome back, playerName" message from Game Center when the player authenticates?

Answer 1

Heres a shorter version for Swift:

//Call it right after create this object:
let localPlayer = GKLocalPlayer.localPlayer()
suppressGCBanner(0, originalWindowCount: UIApplication.sharedApplication().windows.count)

////////////////////////////////////////////////////////////////////////

static func suppressGCBanner(iteration: Int, originalWindowCount: Int) {
    let windows = UIApplication.sharedApplication().windows

    if windows.count > originalWindowCount {
        let window = windows[1]

        if window.respondsToSelector("currentBannerViewController") || window.respondsToSelector("bannerSemaphore") {
            print("Found banner, killing it \(iteration)")
            window.hidden = true
            return
        }
    }

    if iteration > 200 {
        print("suppressGCBanner: timeout, bailing")
        return
    }

    runThisAfterDelay(seconds: 0.02, after: {
        suppressGCBanner(iteration + 1, originalWindowCount: originalWindowCount)
    })
}

static func runThisAfterDelay(seconds seconds: Double, after: () -> ()) {
    let time = dispatch_time(DISPATCH_TIME_NOW, Int64(seconds * Double(NSEC_PER_SEC)))
    dispatch_after(time, dispatch_get_main_queue(), after)
}