Adjust UILabel height to text

淺唱寂寞╮ 提交于 2019-11-26 12:47:30
Anorak

I've just put this in a playground and it works for me.

Updated for Swift 4.0

import UIKit

 func heightForView(text:String, font:UIFont, width:CGFloat) -> CGFloat{
    let label:UILabel = UILabel(frame: CGRectMake(0, 0, width, CGFloat.greatestFiniteMagnitude))
    label.numberOfLines = 0
    label.lineBreakMode = NSLineBreakMode.byWordWrapping
    label.font = font
    label.text = text

    label.sizeToFit()
    return label.frame.height
}

let font = UIFont(name: "Helvetica", size: 20.0)

var height = heightForView("This is just a load of text", font: font, width: 100.0)

Swift 3:

func heightForView(text:String, font:UIFont, width:CGFloat) -> CGFloat{
    let label:UILabel = UILabel(frame: CGRect(x: 0, y: 0, width: width, height: CGFloat.greatestFiniteMagnitude))
    label.numberOfLines = 0
    label.lineBreakMode = NSLineBreakMode.byWordWrapping
    label.font = font
    label.text = text
    label.sizeToFit()

    return label.frame.height
}

If you are using AutoLayout, you can adjust UILabel height by config UI only.

For iOS8 or above

  • Set constraint leading/trailing for your UILabel
  • And change the lines of UILabel from 1 to 0

For iOS7

  • First, you need to add contains height for UILabel
  • Then, modify the Relation from Equal to Greater than or Equal

  • Finally, change the lines of UILabel from 1 to 0

Your UILabel will automatically increase height depending on the text

I create this extension if you want

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

I have strong working solution.

in layoutSubviews:

    _title.frame = CGRect(x: 0, y: 0, width: bounds.width, height: 0)
    _title.sizeToFit()
    _title.frame.size = _title.bounds.size

in text setter:

    _title.text = newValue
    setNeedsLayout()

UPD. of course with this UILabel settings:

    _title.lineBreakMode = .ByWordWrapping
    _title.numberOfLines = 0

Just by setting:

label.numberOfLines = 0

The label automatically adjusts its height based upon the amount of text entered.

based on Anorak's answer, I also agree with Zorayr's concern, so I added a couple of lines to remove the UILabel and return only the CGFloat, I don't know if it helps since the original code doesn't add the UIabel, but it doesn't throw error, so I'm using the code below:

func heightForView(text:String, font:UIFont, width:CGFloat) -> CGFloat{

    var currHeight:CGFloat!

    let label:UILabel = UILabel(frame: CGRectMake(0, 0, width, CGFloat.max))
    label.numberOfLines = 0
    label.lineBreakMode = NSLineBreakMode.ByWordWrapping
    label.font = font
    label.text = text
    label.sizeToFit()

    currHeight = label.frame.height
    label.removeFromSuperview()

    return currHeight
}

In swift 4.1 and Xcode 9.4.1

Only 3 steps

Step 1)

//To calculate height for label based on text size and width
func heightForView(text:String, font:UIFont, width:CGFloat) -> CGFloat {
    let label:UILabel = UILabel(frame: CGRect(x: 0, y: 0, width: width, height: CGFloat.greatestFiniteMagnitude))
    label.numberOfLines = 0
    label.lineBreakMode = NSLineBreakMode.byWordWrapping
    label.font = font
    label.text = text

    label.sizeToFit()
    return label.frame.height
}

Step 2)

//Call this function
let height = heightForView(text: "This is your text", font: UIFont.systemFont(ofSize: 17), width: 300)
print(height)//Output : 41.0

Step 3)

//This is your label
let proNameLbl = UILabel(frame: CGRect(x: 0, y: 20, width: 300, height: height))
proNameLbl.text = "This is your text"
proNameLbl.font = UIFont.systemFont(ofSize: 17)
proNameLbl.numberOfLines = 0
proNameLbl.lineBreakMode = .byWordWrapping
infoView.addSubview(proNameLbl)

The solution suggested by Anorak as a computed property in an extension for UILabel:

extension UILabel
{
var optimalHeight : CGFloat
    {
        get
        {
            let label = UILabel(frame: CGRectMake(0, 0, self.frame.width, CGFloat.max))
            label.numberOfLines = 0
            label.lineBreakMode = self.lineBreakMode
            label.font = self.font
            label.text = self.text

            label.sizeToFit()

            return label.frame.height
         }
    }
}

Usage:

self.brandModelLabel.frame.size.height = self.brandModelLabel.optimalHeight)

Following on @Anorak answer, i added this extension to String and sent an inset as a parameter, because a lot of times you will need a padding to your text. Anyway, maybe some you will find this usefull.

extension String {

    func heightForWithFont(font: UIFont, width: CGFloat, insets: UIEdgeInsets) -> CGFloat {

        let label:UILabel = UILabel(frame: CGRectMake(0, 0, width + insets.left + insets.right, CGFloat.max))
        label.numberOfLines = 0
        label.lineBreakMode = NSLineBreakMode.ByWordWrapping
        label.font = font
        label.text = self

        label.sizeToFit()
        return label.frame.height + insets.top + insets.bottom
    }
}

Here is how to calculate the text height in Swift. You can then get the height from the rect and set the constraint height of the label or textView, etc.

let font = UIFont(name: "HelveticaNeue", size: 25)!
let text = "This is some really long text just to test how it works for calculating heights in swift of string sizes. What if I add a couple lines of text?"

let textString = text as NSString

let textAttributes = [NSFontAttributeName: font]

let textRect = textString.boundingRectWithSize(CGSizeMake(320, 2000), options: .UsesLineFragmentOrigin, attributes: textAttributes, context: nil)

Swift 4.0

self.messageLabel = UILabel(frame: CGRect(x: 70, y: 60, width:UIScreen.main.bounds.width - 80, height: 30)

messageLabel.text = message

messageLabel.lineBreakMode = .byWordWrapping //in versions below swift 3 (messageLabel.lineBreakMode = NSLineBreakMode.ByWordWrapping)    
messageLabel.numberOfLines = 0 //To write any number of lines within a label scope

messageLabel.textAlignment = .center

messageLabel.textColor = UIColor.white

messageLabel.font = messageLabel.font.withSize(12)

messageLabel.sizeToFit()

Blockquote NSParagraphStyle.LineBreakMode, apply to entire paragraphs, not words within paragraphs.This property is in effect both during normal drawing and in cases where the font size must be reduced to fit the label’s text in its bounding box. This property is set to byTruncatingTail by default.

This link describes the storyboard way of doing the same

just call this method where you need dynamic Height for label

func getHeightforController(view: AnyObject) -> CGFloat {
    let tempView: UILabel = view as! UILabel
    var context: NSStringDrawingContext = NSStringDrawingContext()
    context.minimumScaleFactor = 0.8

    var width: CGFloat = tempView.frame.size.width

    width = ((UIScreen.mainScreen().bounds.width)/320)*width

    let size: CGSize = tempView.text!.boundingRectWithSize(CGSizeMake(width, 2000), options:NSStringDrawingOptions.UsesLineFragmentOrigin, attributes: [NSFontAttributeName: tempView.font], context: context).size as CGSize

    return size.height
}

Swift 4.0

Instead of calculating the text/label height, I just resize the label after inserting the (dynamic) text.

Assuming that myLabel is the UILabel in question:

let myLabel = UILabel(frame: CGRect(x: 0, y: 0, width: *somewidth*, height: *placeholder, e.g. 20*))
myLabel.numberOfLines = 0
myLabel.lineBreakMode = .byWordWrapping
...

And now comes the fun part:

var myLabelText: String = "" {
   didSet {
      myLabel.text = myLabelText
      myLabel.sizeToFit()
   }
}

The Swift 4.1 extension method to calculate label height:

extension UILabel {

    func heightForLabel(text:String, font:UIFont, width:CGFloat) -> CGFloat {
        let label:UILabel = UILabel(frame: CGRect(x: 0, y: 0, width: width, height: CGFloat.greatestFiniteMagnitude))
        label.numberOfLines = 0
        label.lineBreakMode = NSLineBreakMode.byWordWrapping
        label.font = font
        label.text = text

        label.sizeToFit()
        return label.frame.height
    }

}

To make label dynamic in swift , don't give height constarint and in storyboard make label number of lines 0 also give bottom constraint and this is the best way i am handling dynamic label as per their content size .

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