UILabel Bold / Highlight All occurrences SubString

Question

I have multiple UILabels within a Custom Table cell. These labels contain varied text or varied length.

As it stands i have UILabel Subclassed allowing me to implement these methods

- (void)boldRange:(NSRange)range {
if (![self respondsToSelector:@selector(setAttributedText:)]) {
    return;
}
NSMutableAttributedString *attributedText;
if (!self.attributedText) {
    attributedText = [[NSMutableAttributedString alloc] initWithString:self.text];
} else {
    attributedText = [[NSMutableAttributedString alloc]initWithAttributedString:self.attributedText];
}
     [attributedText setAttributes:@{NSFontAttributeName:[UIFont boldSystemFontOfSize:self.font.pointSize]} range:range];
self.attributedText = attributedText;
NSLog(@"%@", NSStringFromRange(range));
}

- (void)boldSubstring:(NSString*)substring {
    NSRange range = [self.text rangeOfString:substring];
    [self boldRange:range];
}

This allows me to call [cell.StoryLabel boldSubstring:@"test"]; which will BOLD the first occurrence of the word 'test'.

What i am after is the ability to either create new subclass methods or extend the ones i already have, to allow me to replace ALL occurrences of a specified word within the label.

I have looked into a number of methods including 3rd party frameworks. The trouble i have is this is a learning process for me. I would be far more beneficial for me to try and complete this myself.

Thanks in advance!

Answer 1

rangeOfString returns the first occurrence, that's normal behavior. From the Doc:

Finds and returns the range of the first occurrence of a given string within the receiver.

You could use a NSRegularExpression, and use matchesInString:options:range to get a NSArray of NSTextCheckingResult (that have a NSRange property), an use a for loop to bold it.

This should do the trick:

- (void)boldSubstring:(NSString*)substring
{
    if (![self respondsToSelector:@selector(setAttributedText:)])
    {
        return;
    }

    NSError *error;
    NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern: substring options:NSRegularExpressionCaseInsensitive error:&error];

    if (!error)
    {
        NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:[self text]];
        NSArray *allMatches = [regex matchesInString:[self text] options:0 range:NSMakeRange(0, [[self text] length])];
        for (NSTextCheckingResult *aMatch in allMatches)
        {
            NSRange matchRange = [aMatch range];
            [attributedString setAttributes:@{NSFontAttributeName:[UIFont boldSystemFontOfSize:self.font.pointSize]} range: matchRange];
        }
        [self setAttributedText:attributedString];
    }
}