How to adjust and make the width of a UILabel to fit the text size?

In my project, there is a UILabel with text. The font size is 16pt. The text contents are changed depending on different cases. I hope it can automatically adjust the width of UILabel to fit the total width of texts without stretching.

Is it possible?

This assumes you have already set the font:

label.text = @"some text";
[label sizeToFit];

You will also need to define a maximum width, and tell your program what to do if sizeToFit gives you a width greater than that maximum.

Here's how to do it, suppose the following messageLabel is the label you want to have the desired effect. Now, try these simple line of codes:

    // Set width constraint for label; it's actually the width of your UILabel
    CGFloat constrainedWidth = 240.0f;
    // Calculate space for the specified string
    CGSize sizeOfText = [yourText sizeWithFont:yourFont constrainedToSize:CGSizeMake(constrainedWidth, CGFLOAT_MAX) lineBreakMode:UILineBreakModeWordWrap];
    UILabel *messageLabel = [[UILabel alloc] initWithFrame:CGRectMake(20,20,constrainedWidth,sizeOfText.height)];
    messageLabel.text = yourText;
    messageLabel.numberOfLines = 0;// This will make the label multiline

NSString *txt1=@"I am here.";
CGSize stringsize1 = [txt1 sizeWithFont:[UIFont systemFontOfSize:14]]; 
[label setFrame:CGRectMake(x,y,stringsize1.width,hieght)];
[label setText:txt1];
           
 

I see three options here.

First, make label's size big enough to hold any text. That's most simple, but does not always work well - depends on its surrounding views.

Second, Label can adapt size of the font for longer text (adjustsFontSizeToFitWidth property). This is often not desirable, different fonts in elements might look ugly.

Last option is to programmatically resize the label according to its currently holding text. To calculate the size required to hold the text with current font use something like this:

CGSize textSize = [[someLabel text] sizeWithFont:[someLabel font] forWidth:someLabel.bounds.size.width lineBreakMode:UILineBreakModeWordWrap];

If you set your font and its size already and if you have your frame defined, try using the following for these two common conditions:

if (label.text.length > maxCharPerLine) [label setNumberOfLines:0]; // infinite lines
else [label setNumberOfLines:1]; // one line only
    
// Adjust your font size to fit your desired width.
[label setAdjustsFontSizeToFitWidth:YES];

Using Auto Layout:

In the ViewController:

override func viewDidLoad() {
    super.viewDidLoad()

    sampleLabel.text = "Electrical Maintenance and Repair"
    sampleLabel.sizeToFit()
}

Follow this.

CGSize stringsize = [yourString sizeWithFont:[UIFont systemFontOfSize:fontSize]]; 
[label setFrame:CGRectMake(x,y,stringsize.width,height)];
[label setText: yourString];

As sizeWithFont is depreciated in IOS 7.0 then you below code

#define SYSTEM_VERSION_LESS_THAN(v) ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] == NSOrderedAscending)



 if (SYSTEM_VERSION_LESS_THAN(@"7.0")) {
        // code here for iOS 5.0,6.0 and so on
        CGSize fontSize = [itemCat_text sizeWithFont:[UIFont fontWithName:@"Helvetica" size:12]];
    } else {
        // code here for iOS 7.0
         fontSize = [itemCat_text sizeWithAttributes:
                           @{NSFontAttributeName:
                                 [UIFont fontWithName:@"Helvetica" size:12]}];
    }