I am trying to make a simple Coffee Calculator. I need to display the amount of coffee in grams. The "g" symbol for grams needs to be attached to my UILabel that I am using to display the amount. The numbers in the UILabel are changing dynamically with user input just fine, but I need to add a lower case "g" on the end of the string that is formatted differently from the updating numbers. The "g" needs to be attached to the numbers so that as the number size and position changes, the "g" "moves" with the numbers. I'm sure this problem has been solved before so a link in the right direction would be helpful as I've googled my little heart out.

I've searched through the documentation for an attributed string and I even downloded an "Attributed String Creator" from the app store, but the resulting code is in Objective-C and I am using Swift. What would be awesome, and probably helpful to other developers learning this language, is a clear example of creating a custom font with custom attributes using an attributed string in Swift. The documentation for this is very confusing as there is not a very clear path on how to do so. My plan is to create the attributed string and add it to the end of my coffeeAmount string.

var coffeeAmount: String = calculatedCoffee + attributedText

其中calculatedCoffee是一个Int转换为字符串和“attributedText”是小写的“g”与自定义字体,我试图创建。也许我做错了。任何帮助都是感激的!


当前回答

请考虑使用Prestyler

import Prestyler
...
Prestyle.defineRule("$", UIColor.red)
label.attributedText = "\(calculatedCoffee) $g$".prestyled()

其他回答

斯威夫特有一个非常甜蜜的方式来做到这一点,真的不需要任何工作。只需提供应该匹配的模式以及应用于它的属性。它们在很多方面都很有用,去看看吧。

``` Swift
let defaultGenreText = NSAttributedString(string: "Select Genre - Required")
let redGenreText = defaultGenreText.applying(attributes: [NSAttributedString.Key.foregroundColor : UIColor.red], toRangesMatching: "Required")
``

如果你有多个地方,这将被应用,你只希望它发生在特定的实例,那么这个方法将不起作用。

你可以一步完成,只是分开时更容易阅读。

斯威夫特3、4、5所示

使用下面的代码为文本颜色,字体,背景颜色和下划线/下划线颜色

    let text = "swift is language"
    let attributes = [NSAttributedString.Key.foregroundColor: UIColor.red, NSAttributedString.Key.backgroundColor: UIColor.blue,NSAttributedString.Key.font: UIFont.systemFont(ofSize: 25.0),NSAttributedString.Key.underlineColor: UIColor.white,NSAttributedString.Key.underlineStyle: NSUnderlineStyle.single.rawValue] as [NSAttributedString.Key : Any]
        
    let textAttribute = NSAttributedString(string: text, attributes: attributes)
    swiftLabel1.attributedText = textAttribute

Swift使用与Obj-C相同的NSMutableAttributedString。你通过传入计算值作为字符串来实例化它:

var attributedString = NSMutableAttributedString(string:"\(calculatedCoffee)")

现在创建带属性的g字符串。注意:UIFont.systemFontOfSize(_)现在是一个可失败的初始化式,所以在你可以使用它之前,它必须被解除包装:

var attrs = [NSFontAttributeName : UIFont.systemFontOfSize(19.0)!]
var gString = NSMutableAttributedString(string:"g", attributes:attrs)

然后追加:

attributedString.appendAttributedString(gString)

然后你可以像这样设置UILabel来显示NSAttributedString:

myLabel.attributedText = attributedString

属性可以直接设置在swift 3…

    let attributes = NSAttributedString(string: "String", attributes: [NSFontAttributeName : UIFont(name: "AvenirNext-Medium", size: 30)!,
         NSForegroundColorAttributeName : UIColor .white,
         NSTextEffectAttributeName : NSTextEffectLetterpressStyle])

然后在任何具有属性的类中使用该变量

Swift 5及以上

   let attributedString = NSAttributedString(string:"targetString",
                                   attributes:[NSAttributedString.Key.foregroundColor: UIColor.lightGray,
                                               NSAttributedString.Key.font: UIFont(name: "Arial", size: 18.0) as Any])