在swift中绘制一个中心对齐的文本不能按预期工作

Question

我有一个文字＆＃34; SUGUS＆＃34;我想在100,100点绘制，Textalignment = center。所以我希望有这个角色＆＃34; G＆＃34;在100,100点，因为我喜欢把它放在中心位置。

有人知道我在跟踪代码方面做错了吗？

                var s: NSString=NSString(string: "SUGUS");
                var iTextPositionX:Int = 100;
                var iTextPositionY:Int = 100;

                let fieldColor: UIColor = UIColor.darkGrayColor()
                let fieldFont = UIFont(name: "Helvetica Neue", size: 12)
                var paraStyle = NSMutableParagraphStyle()

                paraStyle.lineSpacing = 6.0
                paraStyle.alignment = NSTextAlignment.Center;// <---
                var skew = 0.1

                let attributes = [
                    NSForegroundColorAttributeName: fieldColor,
                    NSParagraphStyleAttributeName: paraStyle,
                    NSObliquenessAttributeName: skew,
                    //NSTextAlignment: textalign,
                    NSFontAttributeName: fieldFont!
                ]

                var Textpoint:CGPoint=CGPoint(x: iTextPositionX, y: iTextPositionY);
                s.drawAtPoint(Textpoint, withAttributes: attributes);