How do I change the font size of a UILabel in Swift?

问题

label.font.pointSize is read-only, so I'm not sure how to change it.

回答1:

You can do it like this:

label.font = UIFont(name: label.font.fontName, size: 20)

Or like this:

label.font = label.font.withSize(20)

This will use the same font. 20 can be whatever size you want of course.

Note: The latter option will overwrite the current font weight to regular so if you want to preserve the font weight use the first option.

Swift 3 Update:

label.font = label.font.withSize(20)

Swift 4 Update:

label.font = label.font.withSize(20)

label.font = UIFont(name:"fontname", size: 20.0)

and if you use the system fonts

label.font = UIFont.systemFont(ofSize: 20.0)
label.font = UIFont.boldSystemFont(ofSize: 20.0)
label.font = UIFont.italicSystemFont(ofSize: 20.0)

回答2:

I think the best way to do this - if keeping the same font that is already assigned to the UILabel would be:

(using Swift)

label.font = label.font.fontWithSize(20)

(using Swift 3)

label.font = label.font.withSize(20)

Ideally I would set this in the viewDidLayoutSubviews method, as it doesn't need to change every time the view appears.

回答3:

label.font = UIFont.systemFontOfSize(20)

回答4:

We can set font as per our requirement like,

label.font = UIFont(name: "Avenir-Light", size: 15.0)
label.font = UIFont.boldSystemFontOfSize(15)
label.font = UIFont.italicSystemFontOfSize(15)
label.font = UIFont.systemFontOfSize(17)

回答5:

If you want just change size of your font i create this extension

// Add extension

extension UILabel {
    func setSizeFont (sizeFont: Double) {
        self.font =  UIFont(name: self.font.fontName, size: sizeFont)!
        self.sizeToFit()
    }
}

// Use

myLabel.setSizeFont(60)

回答6:

You can give like this also

labelName.font = UIFont(name: "systemFont", size: 30)

回答7:

In Swift 3 again...

myLabel.font = myLabel.font.withSize(18)

回答8:

Swift-3.1

label.font = UIFont.systemFont(ofSize: 12)

回答9:

In swift3, suppose your UILable name is myLable and you want to change its font size do this

myLable.font = UIFont.systemFont(ofSize: 10)

回答10:

You can use an extension.

import UIKit

extension UILabel {

    func sizeFont(_ size: CGFloat) {
        self.font = self.font.withSize(size)
    }
}

To use it:

self.myLabel.fontSize(100)

回答11:

Apple keep changing things for no reason: Swift 4+:

myLabel.font = UIFont.systemFont(ofSize: 16)

thanks apple for wasting people time to figure out what "font size" methods they need to use!

回答12:

Programmatically

label.font = UIFont.systemFont(ofSize: 20.0)
label.font = UIFont.boldSystemFont(ofSize: 20.0)
label.font = UIFont.italicSystemFont(ofSize: 20.0)

label.font = UIFont(name:"Helvetica Neue", size: 20.0)//Set your font name here

Through Story board

To display multiple lines set 0(Zero), this will display more than one line in your label.

If you want to display only 2 lines set 2.

If you want to set minimum font size for label Click Autoshrink and Select Minimum Font Size option

See below screens

Here set minimum font size

EX: 9 (In this image)

If your label get more text at that time your label text will be shrink upto 9

回答13:

Swift 4.2

myLabel.font = UIFont.systemFont(ofSize: 12)

回答14:

I used fontWithSize for a label with light system font, but it changes back to normal system font.

If you want to keep the font's traits, better to include the descriptors.

label.font = UIFont(descriptor: label.font.fontDescriptor(), size: 16.0)

回答15:

In Swift 3:

label = UIFont.systemFont(ofSize: 20)

and to use system preset sizes, for example:

label = UIFont.systemFont(ofSize: UIFont.smallSystemFontSize)

回答16:

Swift 3

label.font.withSize(16)

回答17:

Swift 3.1

import UIKit

extension UILabel {
    var fontSize: CGFloat {
        get {
            return self.font.pointSize
        }
        set {
            self.font =  UIFont(name: self.font.fontName, size: newValue)!
            self.sizeToFit()
        }
    }
}

回答18:

swift 4:

label.font = UIFont("your font name", size: 15)

also if you want to set the label font in all views in your project try this in appDelegate>didFinishLaunch: UILabel.appearance().font = UIFont("your font name", size: 15)

回答19:

In case you want to use custom font with bold option:

nameLabel.font = UIFont(name: "GillSans-Bold", size: 27)

回答20:

SWIFT 3.1

Label.font = Label.font.withSize(NewValue)

回答21:

It's very easy and convenient to change font size from storyboard, and you can instantly see the result of the change.

Actually, it's also very easy to change other font attributes on storyboard too, like style, font family, etc.

来源：https://stackoverflow.com/questions/24356888/how-do-i-change-the-font-size-of-a-uilabel-in-swift

标签

ios

uilabel

swift