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ios - Programmatically Creating UILabel

I know this should be very simple, but I've been really struggling with creating a UILabel programmatically and getting it to behave the way I would like.

All I want is to be able to create a label, set the maximum attributes as far as height, width and font size, and then have the text get smaller AND/OR just truncate the text to accommodate long strings of text.

Let's say that I want my label to have text that has a maximum width of 380, a maximum height of 20 and a maximum font size of 12.

So here is what I have attempted to do to create such a label:

UILabel *fromLabel = [[UILabel alloc]initWithFrame:CGRectMake(91, 15, 0, 0)];
fromLabel.text = [self fromSender];
fromLabel.font = [UIFont fontWithName:ProximaNovaSemibold size:12]; //custom font
fromLabel.numberOfLines = 1;
fromLabel.baselineAdjustment = YES;
fromLabel.adjustsFontSizeToFitWidth = YES;
fromLabel.adjustsLetterSpacingToFitWidth = YES;
fromLabel.size = [fromLabel.text sizeWithFont:fromLabel.font constrainedToSize:CGSizeMake(380, 20) lineBreakMode:NSLineBreakByTruncatingTail];
fromLabel.minimumScaleFactor = MIN_SCALE_FACTOR;
fromLabel.clipsToBounds = YES;
fromLabel.backgroundColor = [UIColor clearColor];
fromLabel.textColor = [UIColor blackColor];
fromLabel.textAlignment = NSTextAlignmentLeft;
[collapsedViewContainer addSubview:fromLabel];

Ok, so the label appears, but the text is larger than 12 and the height always comes out to be 21!? Even if I change the height and text size values to extreme sizes, this code creates a label of some fixed size that can't be adjusted. The only thing I can seem to make smaller is the width.

I must be over looking something basic, but I really can't figure out how to get my desired result, nor do I understand why I'm getting the behavior that I am getting.

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1 Answer

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Does the following work ?

UIFont * customFont = [UIFont fontWithName:ProximaNovaSemibold size:12]; //custom font
NSString * text = [self fromSender];

CGSize labelSize = [text sizeWithFont:customFont constrainedToSize:CGSizeMake(380, 20) lineBreakMode:NSLineBreakByTruncatingTail];

UILabel *fromLabel = [[UILabel alloc]initWithFrame:CGRectMake(91, 15, labelSize.width, labelSize.height)];
fromLabel.text = text;
fromLabel.font = customFont;
fromLabel.numberOfLines = 1;
fromLabel.baselineAdjustment = UIBaselineAdjustmentAlignBaselines; // or UIBaselineAdjustmentAlignCenters, or UIBaselineAdjustmentNone
fromLabel.adjustsFontSizeToFitWidth = YES;
fromLabel.adjustsLetterSpacingToFitWidth = YES;
fromLabel.minimumScaleFactor = 10.0f/12.0f;
fromLabel.clipsToBounds = YES;
fromLabel.backgroundColor = [UIColor clearColor];
fromLabel.textColor = [UIColor blackColor];
fromLabel.textAlignment = NSTextAlignmentLeft;
[collapsedViewContainer addSubview:fromLabel];

edit :?I believe you may encounter a problem using both adjustsFontSizeToFitWidth and minimumScaleFactor. The former states that you also needs to set a minimumFontWidth (otherwhise it may shrink to something quite unreadable according to my test), but this is deprecated and replaced by the later.

edit 2 :?Nevermind, outdated documentation. adjustsFontSizeToFitWidth needs minimumScaleFactor, just be sure no to pass it 0 as a minimumScaleFactor (integer division, 10/12 return 0). Small change on the baselineAdjustment value too.


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