How to know if the word within UILabel was cut - ios

Question

I try to develop autoshrink functionality. I have attributed text, set into a fix-size UILabel. After that I lower the font size and check if the text fits to given container size.
Problem is that UILabel ignores NSLineBreakByWordWrapping if a word is longer than container width. Resulting in I have cut tail word.
Here is the code:
- (void) setCardText:(NSString *)txt {
NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:txt];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle setLineBreakMode:NSLineBreakByWordWrapping];
[paragraphStyle setAlignment:NSTextAlignmentCenter];
[attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [txt length])];
self.cardLabel.attributedText = attributedString;
for (CGFloat fontSize = 40; fontSize >=5; fontSize--) {
[self.cardLabel setFont:[UIFont fontWithName:#"GothamPro-Light" size:fontSize]];
[paragraphStyle setLineSpacing:fontSize*0.3f];
[attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0, [txt length])];
self.cardLabel.lineBreakMode = NSLineBreakByWordWrapping;
[self.cardLabel sizeToFit];
if (self.cardLabel.frame.size.width <= 220) {
[self.cardLabel setFrame:CGRectMake(40, 40, 220, self.cardLabel.frame.size.height)];
}
if (self.cardLabel.frame.size.height <= 210) {
[self.cardLabel setFrame:CGRectMake(40, 40, self.cardLabel.frame.size.width, 210)];
}
if (self.cardLabel.frame.size.width <= 220 && self.cardLabel.frame.size.height <= 210) {
[self.cardLabel setFrame:CGRectMake(40, 40, 220, 210)];
break;
}
};
And here is the result (I'm sorry for screenshot in Russian): http://take.ms/kg2mG
In the third line the word is cut and its ending is moved to the next line.
I guess it happens because initially this word doesn't fit to container width and was forcibly broken in half. I suppose I need sort of cut-word-detector, which tells me to keep lowering font size. Or another guess is to oblige the UILabel to be expanded by “unfit word”. But I can't find anything that does this job.
Also I can explode given string into words and check if every single of them fits to container width. But I think this method is a wheel inventing. Is there something I missed that can easily solve my issue?

Answer 1

The method sizeToFit calls sizeThatFits: which returns the ‘best’ size to fit the current bounds and then resize label. So at first you constrain the label and it has to fit the given width. You can see description of NSLineBreakByWordWrapping - Wrapping occurs at word boundaries, unless the word itself doesn’t fit on a single line.
For your purposes you should allow label to fit the knowingly more wider width than it requires. But it is difficult because the task is to find the best font size and we cannot predict the width. And the best way is to find font size based on the longest word in the text.
So the algorithm:
Detect the longest word, by separating by spaces.
Iteratively, decrease the font size and calculate the size of the longest word while the word is bigger than required width.
Set calculated font to full text and call sizeThatFits.
Please, find the sample code below ("Verdana" font was used for testing)
- (void) setText {
NSString * text = #"Incidental, indirect, secondary, side rival - Побочный, косвенный, второстепенный, боковой соперник";
CGFloat maxWidth = 300.;
[self setText:text toLabel:self.label maxWidth:maxWidth];
}
- (void) setText:(NSString *)text
toLabel:(UILabel*)label
maxWidth:(CGFloat)maxWidth
{
CGFloat fontSize = [self fontSizeOfWord:[self theLongestWord:text]
initialFontSize:40.
constrainedByWidth:maxWidth];
NSMutableAttributedString * attributedString = [self attributedStringForText:text];
[self setupAttributedStirng:attributedString withFontWithSize:fontSize];
label.attributedText = attributedString;
CGRect labelFrame = label.frame;
labelFrame.size = [label sizeThatFits:[attributedString sizeAdaptedForWidth:maxWidth]];
label.frame = labelFrame;
}
- (NSString*) theLongestWord:(NSString*)text {
NSArray * words = [text componentsSeparatedByString:#" "];
NSUInteger longestLength = 0;
NSUInteger index = NSNotFound;
for(int i = 0; i < words.count; i++) {
NSString * word = words[i];
CGFloat length = word.length;
if(length > longestLength) {
longestLength = length;
index = i;
}
}
return (index != NSNotFound ? words[index] : nil);
}
- (CGFloat)fontSizeOfWord:(NSString *)word
initialFontSize:(CGFloat)initialFontSize
constrainedByWidth:(CGFloat)maxWidth
{
NSMutableAttributedString * wordString = [self attributedStringForText:word];
CGFloat fontSize = initialFontSize;
for (; fontSize >= 5.; --fontSize) {
[self setupAttributedStirng:wordString
withFontWithSize:fontSize];
CGSize wordSize = [wordString sizeAdaptedForWidth:CGFLOAT_MAX];
if(wordSize.width <= maxWidth){
break;
}
}
return fontSize;
}
- (NSMutableAttributedString*) attributedStringForText:(NSString*)text {
return (text&&text.length ? [[NSMutableAttributedString alloc] initWithString:text]:nil);
}
- (void)setupAttributedStirng:(NSMutableAttributedString *)attributedString
withFontWithSize:(CGFloat)fontSize
{
NSMutableParagraphStyle *paragraphStyle = [NSMutableParagraphStyle new];
[paragraphStyle setLineBreakMode:NSLineBreakByWordWrapping];
[paragraphStyle setAlignment:NSTextAlignmentCenter];
UIFont * font = [UIFont fontWithName:#"Verdana" size:fontSize];
[paragraphStyle setLineSpacing:fontSize*0.3f];
NSDictionary * attributes = #{NSParagraphStyleAttributeName: paragraphStyle,
NSFontAttributeName: font};
[attributedString addAttributes:attributes
range:NSMakeRange(0, [attributedString length])];
}
Category for NSAttributedString:
#implementation NSAttributedString (AdaptedSize)
- (CGSize) sizeAdaptedForWidth:(CGFloat)width
{
CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((__bridge CFAttributedStringRef)self);
CGSize targetSize = CGSizeMake(width, CGFLOAT_MAX);
CGSize fitSize = CTFramesetterSuggestFrameSizeWithConstraints(framesetter,
CFRangeMake(0, [self length]),
NULL, targetSize, NULL);
CFRelease(framesetter);
return fitSize;
}
#end

Answer 2

Have you tried the UILabel.adjustsFontSizeToWidth property?