NSMutableAttributedString's attribute NSStrikethroughStyleAttributeName doesn't work correctly in iOS8

Question

I have a mutable attributed string without NSStrikethroughStyleAttributeName attribute like this:

NSMutableAttributedString *str1 = [[NSMutableAttributedString alloc] initWithString:@"aaaa" attributes:@{NSStrikethroughStyleAttributeName:[NSNumber numberWithInteger:NSUnderlineStyleSingle]}];

and another mutable attributed string with NSStrikethroughStyleAttributeName attribute like this:

NSMutableAttributedString *str2 = [[NSMutableAttributedString alloc] initWithString:@"bbbb"];

and a whole string containing two strings above:

NSMutableAttributedString *labelString = [[NSMutableAttributedString alloc] init];
[labelString appendAttributedString:str1];
[labelString appendAttributedString:str2];

when I attach the whole string to a UILabel:

_label.attributedText = labelString;

It both display well in iOS7 and iOS8, like this:

~~aaaa~~bbbb

But when I exchange their positions:

[labelString appendAttributedString:str2];
[labelString appendAttributedString:str1];

It display correctly in iOS7 but not correctly in iOS8

ios7: bbbb~~aaaa~~ ios8: bbbbaaaa

It seems that in iOS8, UILabel doesn't render the strikethrough correctly if the first character in the attributed string is not strikethroughed. I think this is a bug in iOS8, is there anyone who encounter the same problem with me?

I am having exactly the same problem. Have you raised a radar? — Oliver Pearmain, Sep 22 '14 at 08:43
I've also added an open radar now: http://openradar.appspot.com/18409995 (been raising so many IOS8 thought I may as well learn how open radar works) — Oliver Pearmain, Oct 01 '14 at 15:53

score 10 · Accepted Answer · answered Sep 22 '14 at 15:04

10

NSMutableAttributedString *str2 = [[NSMutableAttributedString alloc] initWithString:@"bbbb" attributes:@{NSStrikethroughStyleAttributeName:[NSNumber numberWithInteger:NSUnderlineStyleNone]}];

it should help

answered Sep 22 '14 at 15:04

Yuriy Katkov

116
1
2

This also magically fixed my problem. I was attempting to highlight part of an attributed string by setting the `NSBackgroundColorAttributeName` with a color and an `NSRange`. The code worked perfectly on iOS 7, but I found that in iOS 8 the highlighting only worked if the range had a location of 0; any other value and it wasn't drawn. Creating the attributed string with your code fixed my problem somehow. – MusiGenesis Oct 15 '14 at 15:02

score 8 · Answer 2 · edited Nov 24 '14 at 13:46

On iOS8.1.1 we have more problems with setting NSMutableAttributedString, like with NSStrikethroughStyleAttributeName.

If your attributes are not changing try this and it will be.

I started reasoning by the UILabel that is spirit to chaneger attributes, so if we assume that the NSStrikethroughStyleAttributeName not initialized the label text so we will need the initialize it .

What I do is initializing mutableAttributedString by a none NSStrikethroughStyleAttributeName and change this attribute to highlight: result is:

NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString: myString attributes: @ {NSStrikethroughStyleAttributeName: @ (NSUnderlineStyleNone)}];
             [string addAttributes: @ {NSStrikethroughStyleAttributeName: @ (NSUnderlineStyleSingle)} range: [myString rangeOfString: mySubString]];
[MyLabel setAttributedText: string];

effective result <= iOS8.1.1

It works when MyLabel.numberOfLines is NOT 1. I tested it in iOS 8.1 simulator. — Joey, May 13 '15 at 00:33

score 3 · Answer 3 · answered Sep 25 '14 at 11:49

3

Fix for the bug in iOS8: Strike Through first letter of the string with clear color and then Strike through the text in which ever range you want.

answered Sep 25 '14 at 11:49

Sanjeeva kumar kalva

59
2

score 1 · Answer 4 · edited May 28 '15 at 02:35

When you are not starting the index from 0, try this:

NSMutableAttributedString *attributedStr = [[NSMutableAttributedString alloc] initWithString:@"Hello"];
[attributedStr addAttributes:@{NSStrikethroughStyleAttributeName : @(NSUnderlineStyleSingle)} range:NSMakeRange(1, str.length)];
[attributedStr addAttributes:@{NSStrikethroughStyleAttributeName : @(NSUnderlineStyleNone)} range:NSMakeRange(0, 1)];

score 1 · Answer 5 · edited Jul 17 '19 at 15:06

1

When you add NSStrikethroughStyleAttributeName, you should also add NSBaselineOffsetAttributeName, which is set to 0. And in swift, you should use the rawValue of NSUnderlineStyle.

edited Jul 17 '19 at 15:06

Catarina Ferreira

1,824
5
17
26

answered Jun 22 '17 at 09:03

贺彦文

101
1
1

score 0 · Answer 6 · answered Sep 24 '14 at 00:33

0

I see the same issue and changing NSStrikethroughStyleAttributeName's value to NSUnderlineStyleNone doesn't fix it. Sure seems like iOS 8 bug.

answered Sep 24 '14 at 00:33

amit

1
2

2

Don't change the value to NSUnderlineStyleNone. Just add a NSStrikethroughStyleAttributeName attribute with value NSUnderlineStyleNone to those text which is not strikethroughed. – Richard Sep 24 '14 at 04:12

NSMutableAttributedString's attribute NSStrikethroughStyleAttributeName doesn't work correctly in iOS8

6 Answers6

Linked