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How to add line break for UILabel?

Let see that I have a string look like this:

NSString *longStr = @"AAAAA\nBBBBB\nCCCCC";  

How do I make it so that the UILabel display the message like this

AAAAA BBBBB CCCCC

I don't think \n is recognized by UILabel, so is there anything that I can put inside NSString so that UILabel knows that it has to create a line break there?


C
Community

Use \n as you are using in your string.

Set numberOfLines to 0 to allow for any number of lines.

label.numberOfLines = 0;

Update the label frame to match the size of the text using sizeWithFont:. If you don't do this your text will be vertically centered or cut off.

UILabel *label; // set frame to largest size you want
...
CGSize labelSize = [label.text sizeWithFont:label.font
                          constrainedToSize:label.frame.size
                              lineBreakMode:label.lineBreakMode];
label.frame = CGRectMake(
    label.frame.origin.x, label.frame.origin.y, 
    label.frame.size.width, labelSize.height);

Update : Replacement for deprecated

sizeWithFont:constrainedToSize:lineBreakMode:

Reference, Replacement for deprecated sizeWithFont: in iOS 7?

CGSize labelSize = [label.text sizeWithAttributes:@{NSFontAttributeName:label.font}];

label.frame = CGRectMake(
    label.frame.origin.x, label.frame.origin.y, 
    label.frame.size.width, labelSize.height);

UILabel doesn't have a origin nor size property on iOS? It should probably be label.frame.origin.x etc.
Instead of using sizeWithAttributes then setting the frame, you can just call sizeToFit to work-out and set the frame size in one quick step.
@Hermang, thanks for editing the answer to bring it up to date.
M
Marco

https://i.stack.imgur.com/svM3H.png

Use option-return when typing in the little box in Interface Builder to insert a line feed (\n). In Interface Builder's Label attributes, set # Lines = 0.

Select the label and then change Lines property to 0 like in the above image, and then use \n in your string for line break.


this is super useful!
Looked for this forever. Thanks :)
Fantastic answer. Thanks!
Does not work when setting label programmatically and adding \n (newline) to the string.
amazing. My requirement was to do this with storyboard label only. And this worked like a charm.
m
m4n0

In the interface builder, you can use Ctrl + Enter to insert /n to the position you want. This way could implement the following situation

aaa aaaaaaa


No, I did not down vote. I just edited the answer for better presentation.
So really simple ! +1
Can't believe I never knew that trick! I'd tried shift-Enter because that's fairly standard elsewhere. Thanks for that!
this was exactly what I was looking for! thank you +1!
Great post! Small correction: I believe you mean insert \n instead of insert /n
T
Todd Lehman

If you read a string from an XML file, the line break \n in this string will not work in UILabel text. The \n is not parsed to a line break.

Here is a little trick to solve this issue:

// correct next line \n in string from XML file
NSString *myNewLineStr = @"\n";
myLabelText = [myLabelText stringByReplacingOccurrencesOfString:@"\\n" withString:myNewLineStr];

myLabel.text = myLabelText;

So you have to replace the unparsed \n part in your string by a parsed \n in a hardcoded NSString.

Here are my other label settings:

myLabel.numberOfLines = 0;
myLabel.backgroundColor = [UIColor lightGrayColor];
myLabel.textColor = [UIColor redColor]; 
myLabel.font = [UIFont fontWithName:@"Helvetica Neue" size:14.0];   
myLabel.textAlignment = UITextAlignmentCenter;

Most important is to set numberOfLines to 0 (= unlimited number of lines in label).

No idea why Apple has chosen to not parse \n in strings read from XML?

Hope this helps.


iOS doesn't parse \n when getting strings from Parse.com (I guess it will also happen when getting string from other APIs)
You saved my day. I'm getting string with newline from xml files.
D
Dan

You have to set the numberOfLines property on the UILabel. The default is 1, if you set it to 0 it will remove all limits.


A
AndyOng

Important to note it's \n (backslash) rather than /n.


P
Pranav Kasetti

For those of you who want an easy solution, do the following in the text Label input box in Interface Builder:

Make sure your number of lines is set to 0.

Alt + Enter

(Alt is your option key)

Cheers!


C
CodeOverRide

In Swift 2.2, > iOS 8

I've set Lines = 0 on Storyboard, under Attribute Inspector and linked a referencing outlet to the label. Then use in controller like this:

 @IBOutlet weak var listLabel: UILabel!

 override func viewDidLoad() {
      ...
      listLabel.text = "Line 1\nLine 2\nLine 3\nLine 4\nLine 5\nLine 6\nLine 7\nLine 8"
 }

K
Kate Orlova

In xCode 11, Swift 5 the \n works fine, try the below code:

textlabel.numberOfLines = 0
textlabel.text = "This is line one \n This is line two \n This is line three"

S
Serge Seredenko

Just do it like this

NSString * strCheck = @"A\nB";

strCheck = [strCheck stringByReplacingOccurrencesOfString:@"\\n" withString:@"\n"];  //This is to prevent for fetching string from plist or data structure

label.numberOfLines = 0;

label.lineBreakMode = NSLineBreakByWordWrapping;

label.text = strCheck;

A
Aliaksei Kliuchnikau

// DO not forget to set numberOfLines to zero

UILabel* locationTitle = [[UILabel alloc] initWithFrame:CGRectMake(5, 30, 230, 40)];
locationTitle.font = [UIFont systemFontOfSize:13.0];
locationTitle.numberOfLines = 0;
locationTitle.text = [NSString stringWithFormat:@"Eaton industries pvt. Ltd \nUK Apr 12"];
[cell addSubview:locationTitle];

m
meda

If your using a UILabel you have to remember that the default setting is 1 line, so it does not matter how many breaks you add (\n or \r), you need to make sure it is set to more than one line so it could be allowed to append more lines.

One alternative is to use UITextView which is really meant for multilines.

You can easily achieve this in XCode attribute section of the UILabel, see screenshot:

https://i.stack.imgur.com/x8jFP.png


If you set the number of lines to 0 then you are guaranteed unlimited number of lines, so that if your code changes in the future to say... beyond 3 lines, then you will not run into problems. It's unknown why Apple took this approach.
R
Roi

On Xcode 6, you can just use \n even inside a string when using word wrap. It will work. So for example:

UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(0, 100, screenRect.size.width, 50)];
label.textAlignment = NSTextAlignmentCenter;
label.text = @"This will be on the first line\nfollowed by a line under it.";
label.lineBreakMode = UILineBreakModeWordWrap;
label.numberOfLines = 0;

R
Ranjithkumar

In my case also \n was not working, I fixed issue by keeping number of lines to 0 and copied and pasted the text with new line itself for example instead of Hello \n World i pasted

Hello World

in the interface builder.


Excellent! Works.
F
Fry

Just using label.numberOfLines = 0;


u
user3182143
textLabel.text = @"\nAAAAA\nBBBBB\nCCCCC";
textLabel.numberOfLines = 3; \\As you want - AAAAA\nBBBBB\nCCCCC
textLabel.lineBreakMode = UILineBreakModeWordWrap;
NSLog(@"The textLabel text is - %@",textLabel.text);

u
user3842937

For anyone else that might have trouble with sizeWithFont:constrainedToSize:lineBreakMode: or anyone switching to ios8 (the method is deprecated as of ios7), I adjusted my height by using sizeToFit instead.

UILabel *label;
label.numberOfLines = 0;
// Setup label with desired settings
...
[label sizeToFit];
label.frame = CGRectMake(label.frame.origin.x,     // Or use any desired origin
                         label.frame.origin.y, 
                         label.frame.size.width,   // Or use any desired width
                         label.frame.size.height);

G
Grigori A.
NSCharacterSet *charSet = NSCharacterSet.newlineCharacterSet;
NSString *formatted = [[unformatted componentsSeparatedByCharactersInSet:charSet] componentsJoinedByString:@"\n"];

t
tanya

It seems wrong to me to change the label frame sizes especially when using autolayout. Using the appendFormat method seems more appropriate. Here is my example:

NSMutableString *list = [[NSMutableString alloc] init];
NSArray *textArray = @[@"AAAA", @"BBBB"];
for (NSString *string in textArray) {
    [list appendFormat:@"%@\n", string.mutableCopy];
}
self.label.text = list;
self.label.numberOfLines = 0;

B
BrainyMonkey

If you set your UILable properties from Plain to Attributed...the UILabel will hold multiline text no matter how many paragraphs for along as your UILabel height and width are set to fit the screen area you want to display the text in.


S
Suraj Sonawane

I have faced same problem, and here is, how i solved the problem. Hope this will be helpful for someone.

// Swift 2

   lblMultiline.lineBreakMode = .ByWordWrapping // or use NSLineBreakMode.ByWordWrapping
   lblMultiline.numberOfLines = 0 

// Objective-C

  lblMultiline.lineBreakMode = NSLineBreakByWordWrapping;
  lblMultiline.numberOfLines = 0;

// C# (Xamarin.iOS)

  lblMultiline.LineBreakMode = UILineBreakMode.WordWrap;
  lblMultiline.Lines = 0;