如何在UILabel中控制行距

如果将多个行放在一个文本中，是否可以减少文本之间的间距UILabel？我们可以设置框架，字体大小和行数。我想缩小该标签中两行之间的间距。

我考虑过要在此答案中添加一些新内容，因此我觉得还不错……这是一个Swift答案：

import Cocoa

let paragraphStyle = NSMutableParagraphStyle()
paragraphStyle.lineSpacing = 40

let attrString = NSMutableAttributedString(string: "Swift Answer")
attrString.addAttribute(.paragraphStyle, value:paragraphStyle, range:NSMakeRange(0, attrString.length))

var tableViewCell = NSTableCellView()
tableViewCell.textField.attributedStringValue = attrString

“简短的回答：您不能。要更改文本行之间的间距，您将必须使UILabel成为子类，并滚动自己的drawTextInRect或创建多个标签。”

请参阅：设置UILabel行距

这是一个非常老的答案，其他人已经添加了新的更好的方法来解决此问题。请参阅下面提供的最新答案。

在Xcode 6中，您可以在情节提要中执行以下操作：

从iOS 6开始，您可以将属性字符串设置为UILabel。检查以下内容：

NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:label.text];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
paragraphStyle.lineSpacing = spacing;
[attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, label.text.length)];

label.attributedText = attributedString;

这里说明的解决方案对我不起作用。我发现使用iOS 6 NSAttributeString的方式略有不同：

myLabel.numberOfLines = 0; 
NSString* string = @"String with line one. \n Line two. \n Line three.";
NSMutableParagraphStyle *style  = [[NSMutableParagraphStyle alloc] init];
style.minimumLineHeight = 30.f;
style.maximumLineHeight = 30.f;
NSDictionary *attributtes = @{NSParagraphStyleAttributeName : style,};
myLabel.attributedText = [[NSAttributedString alloc] initWithString:string
                                                         attributes:attributtes];   
[myLabel sizeToFit];

我做了一个简单的扩展，对我来说非常有效：

extension UILabel {
    func setLineHeight(lineHeight: CGFloat) {
        let paragraphStyle = NSMutableParagraphStyle()
        paragraphStyle.lineSpacing = 1.0
        paragraphStyle.lineHeightMultiple = lineHeight
        paragraphStyle.alignment = self.textAlignment

        let attrString = NSMutableAttributedString()
        if (self.attributedText != nil) {
            attrString.append( self.attributedText!)
        } else {
            attrString.append( NSMutableAttributedString(string: self.text!))
            attrString.addAttribute(NSAttributedStringKey.font, value: self.font, range: NSMakeRange(0, attrString.length))
        }
        attrString.addAttribute(NSAttributedStringKey.paragraphStyle, value:paragraphStyle, range:NSMakeRange(0, attrString.length))
        self.attributedText = attrString
    }
}

将其复制到文件中，这样就可以使用它了

myLabel.setLineHeight(0.7)

从Interface Builder（Storyboard / XIB）：

以编程方式：

迅捷4

使用标签扩展名

extension UILabel {

    // Pass value for any one of both parameters and see result
    func setLineSpacing(lineSpacing: CGFloat = 0.0, lineHeightMultiple: CGFloat = 0.0) {

        guard let labelText = self.text else { return }

        let paragraphStyle = NSMutableParagraphStyle()
        paragraphStyle.lineSpacing = lineSpacing
        paragraphStyle.lineHeightMultiple = lineHeightMultiple

        let attributedString:NSMutableAttributedString
        if let labelattributedText = self.attributedText {
            attributedString = NSMutableAttributedString(attributedString: labelattributedText)
        } else {
            attributedString = NSMutableAttributedString(string: labelText)
        }

        // Line spacing attribute
        attributedString.addAttribute(NSAttributedStringKey.paragraphStyle, value:paragraphStyle, range:NSMakeRange(0, attributedString.length))

        self.attributedText = attributedString
    }
}

现在调用分机功能

let label = UILabel()
let stringValue = "How to\ncontrol\nthe\nline spacing\nin UILabel"

// Pass value for any one argument - lineSpacing or lineHeightMultiple
label.setLineSpacing(lineSpacing: 2.0) .  // try values 1.0 to 5.0

// or try lineHeightMultiple
//label.setLineSpacing(lineHeightMultiple = 2.0) // try values 0.5 to 2.0

或使用标签实例（只需复制并执行此代码即可查看结果）

let label = UILabel()
let stringValue = "How to\ncontrol\nthe\nline spacing\nin UILabel"
let attrString = NSMutableAttributedString(string: stringValue)
var style = NSMutableParagraphStyle()
style.lineSpacing = 24 // change line spacing between paragraph like 36 or 48
style.minimumLineHeight = 20 // change line spacing between each line like 30 or 40

// Line spacing attribute
attrString.addAttribute(NSAttributedStringKey.paragraphStyle, value: style, range: NSRange(location: 0, length: stringValue.characters.count))

// Character spacing attribute
attrString.addAttribute(NSAttributedStringKey.kern, value: 2, range: NSMakeRange(0, attrString.length))

label.attributedText = attrString

迅捷3

let label = UILabel()
let stringValue = "How to\ncontrol\nthe\nline spacing\nin UILabel"
let attrString = NSMutableAttributedString(string: stringValue)
var style = NSMutableParagraphStyle()
style.lineSpacing = 24 // change line spacing between paragraph like 36 or 48
style.minimumLineHeight = 20 // change line spacing between each line like 30 or 40
attrString.addAttribute(NSParagraphStyleAttributeName, value: style, range: NSRange(location: 0, length: stringValue.characters.count))
label.attributedText = attrString

现在，iOS 6中还有一个替代答案，即使用带有适当段落样式的NSAttributedString在标签上设置attributedText。有关NSAttributedString的行高的详细信息，请参见以下堆栈溢出答案：

核心文字-NSAttributedString行高正确吗？

这是子类UILabel具有line-height属性的类：https : //github.com/LemonCake/MSLabel

在Swift中作为功能，受DarkDust启发

// Usage: setTextWithLineSpacing(myEpicUILabel,text:"Hello",lineSpacing:20)
func setTextWithLineSpacing(label:UILabel,text:String,lineSpacing:CGFloat)
{
    let paragraphStyle = NSMutableParagraphStyle()
    paragraphStyle.lineSpacing = lineSpacing

    let attrString = NSMutableAttributedString(string: text)
    attrString.addAttribute(NSAttributedString.Key.paragraphStyle, value:paragraphStyle, range:NSMakeRange(0, attrString.length))

    label.attributedText = attrString
}

根据@Mike的Answer，减少的lineHeightMultiple要点。下面的示例对我来说很好用：

    NSString* text = label.text;
    CGFloat textWidth = [text sizeWithAttributes:@{NSFontAttributeName: label.font}].width;
    if (textWidth > label.frame.size.width) {
        NSMutableParagraphStyle *paragraph = [[NSMutableParagraphStyle alloc] init];
        paragraph.alignment = NSTextAlignmentCenter;
        paragraph.lineSpacing = 1.0f;
        paragraph.lineHeightMultiple = 0.75;     // Reduce this value !!!
        NSMutableAttributedString* attrText = [[NSMutableAttributedString alloc] initWithString:text];
        [attrText addAttribute:NSParagraphStyleAttributeName value:paragraph range:NSMakeRange(0, text.length)];
        label.attributedText = attrText;
    }

SWIFT 3有用的扩展，可以更轻松地在行之间设置空间:)

extension UILabel
{
    func setLineHeight(lineHeight: CGFloat)
    {
        let text = self.text
        if let text = text 
        {

            let attributeString = NSMutableAttributedString(string: text)
            let style = NSMutableParagraphStyle()

           style.lineSpacing = lineHeight
           attributeString.addAttribute(NSParagraphStyleAttributeName,
                                        value: style,
                                        range: NSMakeRange(0, text.characters.count))

           self.attributedText = attributeString
        }
    }
}

我找到了一种可以设置实际线条高度（不是因素）的方法，它甚至可以在Interface Builder中实时渲染。请按照以下说明进行操作。代码是用Swift 4编写的。

步骤1：创建一个名为的文件，DesignableLabel.swift并插入以下代码：

import UIKit

@IBDesignable
class DesignableLabel: UILabel {
    @IBInspectable var lineHeight: CGFloat = 20 {
        didSet {
            let paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.minimumLineHeight = lineHeight
            paragraphStyle.maximumLineHeight = lineHeight
            paragraphStyle.alignment = self.textAlignment

            let attrString = NSMutableAttributedString(string: text!)
            attrString.addAttribute(NSAttributedStringKey.font, value: font, range: NSRange(location: 0, length: attrString.length))
            attrString.addAttribute(NSAttributedStringKey.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: attrString.length))
            attributedText = attrString
        }
    }
}

步骤2：将UILabel放到Storyboard / XIB中，并将其类设置为DesignableLabel。等待项目构建（构建必须成功！）。

步骤3：现在您应该在属性窗格中看到一个名为“线高”的新属性。只需设置您喜欢的值，您应该立即看到结果！

这是UILabel的子类，它设置lineHeightMultiple并确保固有高度足够大，不会截断文本。

@IBDesignable
class Label: UILabel {
    override var intrinsicContentSize: CGSize {
        var size = super.intrinsicContentSize
        let padding = (1.0 - lineHeightMultiple) * font.pointSize
        size.height += padding
        return size
    }

    override var text: String? {
        didSet {
            updateAttributedText()
        }
    }

    @IBInspectable var lineHeightMultiple: CGFloat = 1.0 {
        didSet {
            updateAttributedText()
        }
    }

    private func updateAttributedText() {
        let paragraphStyle = NSMutableParagraphStyle()
        paragraphStyle.lineHeightMultiple = lineHeightMultiple
        attributedText = NSAttributedString(string: text ?? "", attributes: [
            .font: font,
            .paragraphStyle: paragraphStyle,
            .foregroundColor: textColor
        ])
        invalidateIntrinsicContentSize()
    }
}

在Swift 2.0中...

添加扩展名：

extension UIView {
    func attributesWithLineHeight(font: String, color: UIColor, fontSize: CGFloat, kern: Double, lineHeightMultiple: CGFloat) -> [String: NSObject] {
        let titleParagraphStyle = NSMutableParagraphStyle()
        titleParagraphStyle.lineHeightMultiple = lineHeightMultiple

        let attribute = [
            NSForegroundColorAttributeName: color,
            NSKernAttributeName: kern,
            NSFontAttributeName : UIFont(name: font, size: fontSize)!,
            NSParagraphStyleAttributeName: titleParagraphStyle
        ]
        return attribute
    }
}

现在，只需将UILabel设置为attributedText：

self.label.attributedText = NSMutableAttributedString(string: "SwiftExample", attributes: attributesWithLineHeight("SourceSans-Regular", color: UIColor.whiteColor(), fontSize: 20, kern: 2.0, lineHeightMultiple: 0.5))    

显然，我添加了一堆您可能不需要的参数。随便玩-随时重写方法-我一直在寻找一堆不同的答案，因此我想将整个扩展发布出来，以防它对某人有所帮助... -rab

Swift3-在UITextView或UILabel扩展中，添加以下函数：

如果您已经在视图中使用了属性字符串（而不是覆盖它们），我添加了一些代码来保留当前属性文本。

func setLineHeight(_ lineHeight: CGFloat) {
    guard let text = self.text, let font = self.font else { return }

    let paragraphStyle = NSMutableParagraphStyle()
    paragraphStyle.lineSpacing = 1.0
    paragraphStyle.lineHeightMultiple = lineHeight
    paragraphStyle.alignment = self.textAlignment

    var attrString:NSMutableAttributedString
    if let attributed = self.attributedText {
        attrString = NSMutableAttributedString(attributedString: attributed)
    } else {
        attrString = NSMutableAttributedString(string: text)
        attrString.addAttribute(NSFontAttributeName, value: font, range: NSMakeRange(0, attrString.length))
    }
    attrString.addAttribute(NSParagraphStyleAttributeName, value:paragraphStyle, range:NSMakeRange(0, attrString.length))
    self.attributedText = attrString
}

另一个答案...如果要以编程方式传递字符串，则需要传递属性字符串而不是常规字符串并更改其样式。（iOS10）

NSMutableAttributedString * attrString = [[NSMutableAttributedString alloc] initWithString:@"Your \nregular \nstring"];
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
[style setLineSpacing:4];
[attrString addAttribute:NSParagraphStyleAttributeName
                   value:style
                   range:NSMakeRange(0, attrString.length)];
_label.attributedText = attrString;

Swift 3扩展名：

    import UIKit

extension UILabel {
    func setTextWithLineSpacing(text: String, lineHeightMultiply: CGFloat = 1.3) {
        let paragraphStyle = NSMutableParagraphStyle()
        paragraphStyle.lineHeightMultiple = lineHeightMultiply
        paragraphStyle.alignment = .center
        let attributedString = NSMutableAttributedString(string: text)
        attributedString.addAttribute(NSParagraphStyleAttributeName, value: paragraphStyle, range: NSRange(location: 0, length: attributedString.length))
        self.attributedText = attributedString
    }
}

这应该有所帮助。然后，您可以在情节提要中将标签分配给此自定义类，并直接在属性中使用其参数：

open class SpacingLabel : UILabel {

    @IBInspectable open var lineHeight:CGFloat = 1 {
        didSet {
            let paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.lineSpacing = 1.0
            paragraphStyle.lineHeightMultiple = self.lineHeight
            paragraphStyle.alignment = self.textAlignment

            let attrString = NSMutableAttributedString(string: self.text!)
            attrString.addAttribute(NSAttributedStringKey.font, value: self.font, range: NSMakeRange(0, attrString.length))
            attrString.addAttribute(NSAttributedStringKey.paragraphStyle, value:paragraphStyle, range:NSMakeRange(0, attrString.length))
            self.attributedText = attrString
        }
    } 
}

Swift 4标签扩展。在传递给函数的情况下创建NSMutableAttributedString，以防属性文本需要额外的属性。

extension UILabel {

    func setLineHeightMultiple(to height: CGFloat, withAttributedText attributedText: NSMutableAttributedString) {

        let paragraphStyle = NSMutableParagraphStyle()
        paragraphStyle.lineSpacing = 1.0
        paragraphStyle.lineHeightMultiple = height
        paragraphStyle.alignment = textAlignment

        attributedText.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: attributedText.length - 1))

        self.attributedText = attributedText
    }
}

这段代码对我有用（肯定是ios 7和ios 8）。

_label.numberOfLines=2;
_label.textColor=[UIColor whiteColor];

NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
paragraphStyle.lineHeightMultiple=0.5;
paragraphStyle.alignment = NSTextAlignmentCenter;
paragraphStyle.lineSpacing = 1.0;

NSDictionary *nameAttributes=@{
                               NSParagraphStyleAttributeName : paragraphStyle,
                               NSBaselineOffsetAttributeName:@2.0
                               };


NSAttributedString *string=[[NSAttributedString alloc] initWithString:@"22m\nago" attributes:nameAttributes];
_label.attributedText=string;

这是我的快速解决方案。子类应同时适用于attributedText和text属性以及characterSpacing + lineSpacing。如果设置了新的字符串或attributedString，它将保留间距。

open class UHBCustomLabel : UILabel {
    @IBInspectable open var characterSpacing:CGFloat = 1 {
        didSet {
            updateWithSpacing()
        }

    }
    @IBInspectable open var lines_spacing:CGFloat = -1 {
        didSet {
            updateWithSpacing()
        }

    }
    open override var text: String? {
        set {
            super.text = newValue
            updateWithSpacing()
        }
        get {
            return super.text
        }
    }
    open override var attributedText: NSAttributedString? {
        set {
            super.attributedText = newValue
            updateWithSpacing() 
        }
        get {
            return super.attributedText
        }
    }
    func updateWithSpacing() {
        let attributedString = self.attributedText == nil ? NSMutableAttributedString(string: self.text ?? "") : NSMutableAttributedString(attributedString: attributedText!)
        attributedString.addAttribute(NSKernAttributeName, value: self.characterSpacing, range: NSRange(location: 0, length: attributedString.length))
        if lines_spacing >= 0 {
            let paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.lineSpacing = lines_spacing
            paragraphStyle.alignment = textAlignment
            attributedString.addAttribute(NSParagraphStyleAttributeName, value:paragraphStyle, range:NSMakeRange(0, attributedString.length))
        }
        super.attributedText = attributedString
    }
}

作为一种快速，简单，智能的解决方法：

对于行数不多的UILabel，可以改用stackViews。

1. 为每一行写一个新标签。
2. 将它们嵌入到StackView中。（选择两个标签->编辑器->嵌入--StackView
3. 调整SpacingStackView到所需的数量

确保将它们垂直堆叠。此解决方案也适用于自定义字体。