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Set UILabel line spacing

如何修改多行UILabel行间距(行间距)?

Edit: Evidently NSAttributedString will do it, on iOS 6 and later. Instead of using an NSString to set the label's text, create an NSAttributedString , set attributes on it, then set it as the .attributedText on the label. The code you want will be something like this:

NSMutableAttributedString* attrString = [[NSMutableAttributedString  alloc] initWithString:@"Sample text"];
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
[style setLineSpacing:24];
[attrString addAttribute:NSParagraphStyleAttributeName
    value:style
    range:NSMakeRange(0, strLength)];
uiLabel.attributedText = attrString;

NSAttributedString's old attributedStringWithString did the same thing, but now that is being deprecated.

For historical reasons, here's my original answer:

Short answer: you can't. To change the spacing between lines of text, you will have to subclass UILabel and roll your own drawTextInRect , create multiple labels, or use a different font (perhaps one edited for a specific line height, see Phillipe's answer).

Long answer: In the print and online world, the space between lines of text is known as "leading" (rhymes with 'heading', and comes from the lead metal used decades ago). Leading is a read-only property of UIFont , which was deprecated in 4.0 and replaced by lineHeight . As far as I know, there's no way to create a font with a specific set of parameters such as lineHeight ; you get the system fonts and any custom font you add, but can't tweak them once installed.

There is no spacing parameter in UILabel , either.

I'm not particularly happy with UILabel 's behavior as is, so I suggest writing your own subclass or using a 3rd-party library. That will make the behavior independent of your font choice and be the most reusable solution.

I wish there was more flexibility in UILabel , and I'd be happy to be proven wrong!

Starting in ios 6 you can set an attributed string in the UILabel:

NSString *labelText = @"some text"; 
NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:labelText];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle setLineSpacing:40];
[attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [labelText length])];
cell.label.attributedText = attributedString ;

You can control line spacing in the storyboard:

duplicate question

From Interface Builder:

在此输入图像描述

Programmatically:

SWift 4

Using label extension

extension UILabel {

    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
    }
}

Now call extension function

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


Or using label instance (Just copy & execute this code to see result)

let label = UILabel()
let stringValue = "Set\nUILabel\nline\nspacing"
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

Swift 3

let label = UILabel()
let stringValue = "Set\nUILabel\nline\nspacing"
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

My solution was to patch the font file itself and fix its line height definitely. http://mbauman.net/geek/2009/03/15/minor-truetype-font-editing-on-a-mac/

I had to modify 'lineGap', 'ascender', 'descender' in the 'hhea' block (as in the blog example).

这个人创建了一个获得行高的类(不使用CoreText,作为MTLabel库): https//github.com/LemonCake/MSLabel

Best thing I found is: https://github.com/mattt/TTTAttributedLabel

It's a UILabel subclass so you can just drop it in, and then to change the line height:

myLabel.lineHeightMultiple = 0.85;
myLabel.leading = 2;

I've found 3rd Party Libraries Like this one:

https://github.com/Tuszy/MTLabel

To be the easiest solution.

Here's some swift-code for you to set the line spacing programmatically

let label = UILabel()

let attributedText = NSMutableAttributedString(string: "Your string")
let paragraphStyle = NSMutableParagraphStyle()

//SET THIS:
paragraphStyle.lineSpacing = 4
//OR SET THIS:
paragraphStyle.lineHeightMultiple = 4

//Or set both :)

let range = NSMakeRange(0, attributedText.length)
attributedText.addAttributes([NSParagraphStyleAttributeName : paragraphStyle], range: range)
label.attributedText = attributedText

Of course, Mike's answer doesn't work if you pass the string programmatically. In this case you need to pass a attributed string and change it's style.

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;

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