您可以将该新子视图添加到您的应用程序窗口。

func attach(sender : UIButton)
{
    // Calculate and replace the frame according to your keyboard frame
    var customView = UIView(frame: CGRect(x: 0, y: self.view.frame.size.height-300, width: self.view.frame.size.width, height: 300))
    customView.backgroundColor = UIColor.redColor()
    customView.layer.zPosition = CGFloat(MAXFLOAT)
    var windowCount = UIApplication.sharedApplication().windows.count
    UIApplication.sharedApplication().windows[windowCount-1].addSubview(customView);
}