iOS - NSAttributedString

NSAttributedString 初始化

NSAttributedString.init(string: "TEST", attributes: [:])

attributes 类型为 [NSAttributedStringKey: Any]
下面开始介绍 NSAttributeStringKey 每一个的作用

如果 NSAttributeStringKey 对应的类型传错参数，文本会为透明色

常用

NSAttributedString.Key.font 字体
NSAttributedString.Key.foregroundColor 字体颜色

NSAttributedString.Key.backgroundColor

文本的背景颜色: UIColor

self.textView.attributedText = NSAttributedString.init(string: "TEST", attributes: [
    NSAttributedString.Key.backgroundColor: UIColor.gray
])

NSAttributedString.Key.backgroundColor: UIColor.gray

NSAttributedString.Key.ligature

表示某些连在一起的字符: NSNumber，默认 0 不连体，1为连体

只有某些字符且某些字体才会发生连体

字体为 PingFangSC-Medium 和 PingFangSC-Semibold 等，会发生连体

self.textView.attributedText = NSAttributedString.init(string: "fiflfi", attributes: [
    NSAttributedString.Key.ligature: 1,
    NSAttributedString.Key.font: UIFont.init(name: "PingFangSC-Medium", size: 17)!
])

NSAttributedString.Key.ligature: 1

NSAttributedString.Key.kern

调整字横向间距

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.kern: 10
])

NSAttributedString.Key.kern: 10

NSAttributedString.Key.strikethroughStyle

新增删除线: NSNumber

// NSNumber 为 NSUnderlineStyle 枚举定义的
NSUnderlineStyleNone: 0 //  无删除线
NSUnderlineStyleSingle: 1 // 单条删除线
NSUnderlineStyleThick: 2 // 粗一点的删除线
NSUnderlineStyleDouble: 9 // 两条删除线

/// 删除线颜色
NSAttributedString.Key.strikethroughColor: UIColor.black

NSUnderlineStyleSingle

NSAttributedString.Key.underlineStyle

下划线: NSNumber

// NSNumber 为 NSUnderlineStyle 枚举定义的
NSUnderlineStyleNone: 0 //  无删除线
NSUnderlineStyleSingle: 1 // 单条删除线
NSUnderlineStyleThick: 2 // 粗一点的删除线
NSUnderlineStyleDouble: 9 // 两条删除线

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.underlineStyle: 9,
])

/// 下划线颜色
NSAttributedString.Key.underlineColor: UIColor.black

NSAttributedString.Key.underlineStyle: 9

NSAttributedString.Key.strokeWidth

文字描边: NSNumber

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.strokeWidth: 2
])

/// 文字描边颜色
NSAttributedString.Key.strokeColor: UIColor.black

NSAttributedString.Key.strokeWidth: 2

NSAttributedString.Key.shadow

文字阴影: NSShadow

let shadow = NSShadow.init()
shadow.shadowColor = UIColor.red
shadow.shadowOffset = CGSize.init(width: 0, height: 2)
shadow.shadowBlurRadius = 5

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.shadow: shadow
])

NSAttributedString.Key.shadow

NSAttributedString.Key.textEffect

图版印刷效果: NSAttributedString.TextEffectStyle，目前只有这一个效果

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.textEffect: NSAttributedString.TextEffectStyle.letterpressStyle.rawValue
])

NSAttributedString.Key.textEffect

NSAttributedString.Key.baselineOffset

文字基线的偏移量: NSNumber

NSAttributedString.Key.writingDirection

文字书写方向: NSNumber 数组

// NSNumber 为 NSWritingDirection 枚举定义的
NSUnderlineStyleNone: 

NSAttributedString.Key.link

添加超链接，点击文本可跳转浏览器打开 URL: URL

self.textView.attributedText = NSAttributedString.init(string: "TEST NONE", attributes: [
    NSAttributedString.Key.link: URL.init(string: "https://www.baidu.com")!
])

NSAttributedString.Key.link

NSAttributedString.Key.obliqueness

文字倾斜: NSNumber

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.obliqueness: -1 // < 0 向左，> 0 向右
])

NSAttributedString.Key.obliqueness: -1

NSAttributedString.Key.expansion

文字的压缩和拉伸: NSNumber

self.textView.attributedText = NSAttributedString.init(string: "TEST TEST", attributes: [
    NSAttributedString.Key.expansion: 1 // < 0 压缩，> 0 拉伸
])

NSTextAttachment

用于图文混编

let attachment = NSTextAttachment.init()
attachment.image = UIImage.init(named: "icon_bluetooth_20")!
/// 可调整图片 y 坐标， > 0 往上移动，< 0 往下移动
attachment.bounds = CGRect.init(x: 0, y: -2, width: 17, height: 17)
let mutableAttrString = NSMutableAttributedString.init(attachment: attachment)
mutableAttrString.append(NSAttributedString.init(string: "TEST TEST"))
self.textView.attributedText = mutableAttrString

NSTextAttachment

NSAttributedString.Key.paragraphStyle

用于编辑段落属性: NSParagraphStyle

let paragraphStyle = NSMutableParagraphStyle.init()
paragraphStyle.lineSpacing = 10 // 行间距
paragraphStyle.paragraphSpacing = 10 // 段间距
paragraphStyle.alignment = .left // 两端对齐方式
paragraphStyle.firstLineHeadIndent = 10 // 首行缩进
paragraphStyle.headIndent = 10 // 整体缩进，首行除外
paragraphStyle.tailIndent =  -30 // 尾部缩进， < 0 abs(tailIndent) 尾部距离右边的距离，> 0 abs(tailIndent) 尾部距离左边的距离

/*

NSLineBreakMode
例句: Happiness is a state of mind.

.byWordWrapping = 0,         // 默认，单词换行，Happiness is a state\n of mind
.byCharWrapping,        // 字符换行，Happiness is a state o\nf mind
.byClipping,        // 直接剪掉，Happiness is a state
.byTruncatingHead,    // "...state of mind"
.byTruncatingTail,    // "Happiness is a..."
.byTruncatingMiddle    //  "Happiness is...of mind"

*/
paragraphStyle.lineBreakMode = .byCharWrapping // 断行方式，文本一行不够展示如何处理
paragraphStyle.minimumLineHeight = 10 // 最小行高
paragraphStyle.maximumLineHeight = 10 // 最大行高
paragraphStyle.baseWritingDirection = .rightToLeft // 书写方向
paragraphStyle.lineHeightMultiple = 1.7 // 行高系数 > 0，在最大行高和最小行高约束之前进行计算
paragraphStyle.paragraphSpacingBefore = 10 // 上一段断末和本段段首之间的距离
paragraphStyle.hyphenationFactor =  // 自动断字，hyphen（短横 - ）将单词断开， 例如 impeachment 断为 im-peachment

self.textView.attributedText = NSAttributedString.init(string: "fiflfi", attributes: [
    NSAttributedString.Key.paragraphStyle: paragraphStyle
])