swift-延时加载函数

//延时加载函数

  func delayLoad(){
        let time: NSTimeInterval = 2.0
        let delay = dispatch_time(DISPATCH_TIME_NOW,
            Int64(time * Double(NSEC_PER_SEC)))
        dispatch_after(delay, dispatch_get_main_queue()) {
            print("2 秒后输出")
        }
    }