ios - float 操作按钮的中心 UIButton 文本，如收件箱应用程序

Question

floatingButton = UIButton(x: blocx, y:blocy, width: imageSize, height: imageSize, target: self, action: "clickedFloatingButton")
floatingButton!.backgroundColor = CozyColors.StatCardSkip
floatingButton!.layer.cornerRadius = floatingButton!.frame.size.width / 2
floatingButton!.setTitle("+", forState: UIControlState.Normal)
floatingButton!.setTitleColor(CozyColors.ThemeWhite, forState: UIControlState.Normal)
floatingButton!.titleLabel?.font = UIFont(name: CozyStyles.ThemeFontName, size: imageSize*2/3)
view.addSubview(floatingButton!)

结果如下:

如您所见，加号按钮未正确对齐到中心。如何在不添加 UILabel 作为 subview 的情况下将它放在中间？

Answer 1

试试这段代码:

    var floatingButton = UIButton(frame: CGRectMake(10, 20, 50, 50))
    floatingButton.backgroundColor = UIColor.redColor()
    floatingButton.layer.cornerRadius = floatingButton.frame.size.width / 2
    floatingButton.setTitle("+", forState: UIControlState.Normal)
    floatingButton.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
    floatingButton.titleLabel?.font = UIFont(name: floatingButton.titleLabel!.font.familyName , size: 50)
    floatingButton.titleEdgeInsets = UIEdgeInsetsMake(-10, 0, 0, 0)
    view.addSubview(floatingButton)