Swift：NSString不能转换为'字符串'

Question

我是新来的Swift，我试图返回一组数组，但现在我陷入了一个错误的圈子。任何帮助，将不胜感激。我可能错过了一些东西，但它确实不喜欢它：

编辑：添加的代码（未设置数组的约束）。

func createButtonWithTitle(title: String) -> UIButton { 

    let button = UIButton(type:.System) as UIButton 
    button.translatesAutoresizingMaskIntoConstraints = false 
    button.setTitle(title, forState: .Normal) 
    button.sizeToFit() 
    button.titleLabel!.font = UIFont.systemFontOfSize(15) 
    button.backgroundColor = UIColor.greenColor() 
    button.setTitleColor(UIColor.whiteColor(), forState: .Normal) 

    return button 
} 

func createRowOfButtons(buttonTitles: [NSString]) -> UIView { 

    var buttons = [UIButton]() 
    let keyboardRowView = UIView() 

    for buttonTitle in buttonTitles{ 

     let button = createButtonWithTitle(buttonTitle as String) 
     buttons.append(button) 
     keyboardRowView.addSubview(button) 
    } 

    addIndividualButtonConstraints(buttons, mainView: keyboardRowView) 

    return keyboardRowView 
} 

func createArraysOfButtons (rowTitles: [NSString]) -> UIView{ 

    var rows = [UIView]() 
    let keyArrayView = UIView() 

    for rowTitle in rowTitles { 
     if let title = rowTitle as? String{ 
      let row = createRowOfButtons(rowTitle as String) 
      rows.append(row) 
      keyArrayView.addSubview(row) 
     } 
    } 
    return keyArrayView 
} 

错误消息：

'NSString' is not implicitly convertible to 'String'; did you mean to use 'as' to explicitly convert?

Answer 1

简单的解决方案：不要使用NSString

func createRowOfButtons(buttonTitles: [String]) -> UIView { 

    var buttons = [UIButton]() 
    let keyboardRowView = UIView() 

    for buttonTitle in buttonTitles{ 

     let button = createButtonWithTitle(buttonTitle) 
     buttons.append(button) 
     keyboardRowView.addSubview(button) 
    } 

    addIndividualButtonConstraints(buttons, mainView: keyboardRowView) 

    return keyboardRowView 
} 

func createArraysOfButtons (rowTitles: [String]) -> UIView{ 

    var rows = [UIView]() 
    let keyArrayView = UIView() 

    for rowTitle in rowTitles { 
     let row = createRowOfButtons([rowTitle]) 
     rows.append(row) 
     keyArrayView.addSubview(row) 
    } 
    return keyArrayView 
} 

的主要问题是，createRowOfButtons预计字符串数组，但你传递该方法的单个字符串。 createRowOfButtons([rowTitle])解决了这个问题。