UIButton 部分更改标题颜色

Question

我想制作像这张图一样的按钮。 为了实现像图片一样，按钮标题的颜色需要部分改变，但我不知道该怎么做。

这是我的代码。

 private let signUpButton = UIButton().then {
    $0.setTitleColor(.black, for: .normal)
    $0.titleLabel?.font = .boldSystemFont(ofSize: 12)
}

Answer 1

为此目的使用

NSMutableAttributedString

private let signUpButton = UIButton().then {
  // Creating gray text part
  let grayButtonText = NSAttributedString(string: "FirstPart", attributes: [.font: UIFont.systemFont(ofSize: 12), .foregroundColor: UIColor.gray ])
  // Creating black text part
  let blackButtonText = NSAttributedString(string: "SecondPart", attributes: [.font: UIFont.systemFont(ofSize: 12), .foregroundColor: UIColor.black ])

  // Merging two parts together
  let buttonTitle = NSMutableAttributedString(attributedString: grayButtonText)
  buttonTitle.append(blackButtonText)
  
  // Set it as a title for ".normal" state
  $0.setAttributedTitle(buttonTitle, for: .normal)
}