Objective-c – Pixel Width of the text in a UILabel

iphoneobjective cuilabel

I need to draw a UILabel striked through. Therefore I subclassed UILabel and implemented it as follows:

@implementation UIStrikedLabel

- (void)drawTextInRect:(CGRect)rect{
    [super drawTextInRect:rect];

    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextFillRect(context,CGRectMake(0,rect.size.height/2,rect.size.width,1));
}
@end

What happens is that the the UILabel is striked through with a line being as long as the whole label, but the text can be shorter.
Is there a way to determine the length of the text in pixels, such that the line can appropriately be drawn?

I'm also open to any other solutions, if known 🙂

Best,
Erik

Best Answer

NSString has a sizeWithAttributes: method that can be used for this. It returns a CGSize structure, so you could do something similar to the following to find the width of the text inside your label.

iOS 7 and higher

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

CGFloat strikeWidth = textSize.width;

iOS <7

Prior to iOS7, you had to use the sizeWithFont: method.

CGSize textSize = [[label text] sizeWithFont:[label font]];

CGFloat strikeWidth = textSize.width;

UILabel has a font property that you can use to dynamically get the font details for your label as i'm doing above.

Hope this helps :)

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