UILabel attributed text not changing

Question

I am having a problem updating the text on a UILabel . My ViewController changes its view property phoneNumberString . My view observes this property change and reacts, changing the label's attributed text. It observes using ReactiveCocoa.

[[RACAble(self.phoneNumberString) distinctUntilChanged]subscribeNext:^(id x) {
    NSString* s=(NSString*)x;
    UIFont* font=[UIFont systemFontOfSize:numbersFontSize weight:UIFontWeightThin];
    NSMutableDictionary* attributesDict=[NSMutableDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil];

    self.phoneNumberLabel.attributedText = [[NSAttributedString alloc]initWithString:s attributes:attributesDict];
    [self.phoneNumberLabel setNeedsDisplay];
    NSLog(@"label att text = %@\nlabel text = %@\ninput string = %@\n==",self.phoneNumberLabel.attributedText,self.phoneNumberLabel.text,x);
}];

It provides the following log:

label att text = +7 (225{
NSFont = "<UICTFont: 0x7a2942c0> font-family: \".SFUIDisplay-Thin\"; font-weight: normal; font-style: normal; font-size: 25.00pt";
}

label text = +7 (225
input string = +7 (225

I need attributed text to be located in my UILabel . The problem is that it provides no changes in the simulator. (Using native [self observeValueForKeyPath...] results in the same effect). I've solved this problem using notifications with the same code. But I have to use KVO.

Additional information:

1. Here is my initialization code (before setting the observer):

     UILabel* phoneNumberLabel=[[UILabel alloc]init]; font=[UIFont systemFontOfSize:numbersFontSize weight:UIFontWeightThin]; attributesDict=[NSMutableDictionary dictionaryWithObjectsAndKeys:font,NSFontAttributeName, nil]; phoneNumberLabel.attributedText=[[NSAttributedString alloc]initWithString:@"+7 " attributes:attributesDict]; 

2. Both methods run on the main thread.

3. The UILabel 's frame is big enough to allocate.

Answer 1

If you have used size classes in .xib to set font of label then attributed text may not work. To work it properly remove size classes from .xib file

Answer 2

It looks like you are missing an assignment of the attribute to a range of the string. For example,

NSMutableAttributedString *attributedPhoneNumber = [[NSMutableAttributedString alloc] initWithString:x];
[attributedPhoneNumber addAttribute:NSFontAttributeName value:font range:NSMakeRange(0, [attributedPhoneNumber length])];
self.phoneNumberLabel.attributedText = attributedPhoneNumber;

Answer 3

Try calling your method in viewDidLayoutSubviews . For me it did the trick. I was doing it in viewDidLoad and it was an issue.