NSStrikethroughStyleAttributeName is not rendered if applied to a sub range of NSMutableAttributedString length

Originator:stefano.piamonti
Number:rdar://31034683 Date Originated:14-Mar-2017
Status:Open Resolved:
Product:iOS Product Version:10.3 beta 2 - 10.3 beta 5
Classification:UI/Usability Reproducible:Always
 
Area:
Foundation

Summary:
A strikethrough (single, double, ...) added as attribute to an instance of NSMutableAttributedString is not rendered if the apply range is not the whole string range. This happens using addAttribute(_ name: String, value: Any, range: NSRange),  insert(_ attrString: NSAttributedString, at loc: Int), append(_ attrString: NSAttributedString),, ...

Steps to Reproduce:
1. Create a NSMutableAttributedString
2. Add some text to it
3. Apply the strikethrough using NSMutableAttributedString attribute to a subrange of the string
4. Add the string to an UILabel

Expected Results:
The substring in the subrange targeted is rendered marked with a strikethrough

Actual Results:
The whole string is rendered without strikethrough

Version:
from 10.3 beta 2 to 10.3 beta 5

Notes:
It's rendered properly with Xcode until 8.2 and on iOS devices with 10.2.x and previous version of iOS

Configuration:
iPhone 5S, iPhone 7+, iPad Air, Xcode playground Version 8.3 beta 4 (8W143q)

Playground (please use Xcode 8.3 beta):
https://cl.ly/2Q0S3v3i0d2c

Comments

substring in iOS xcode 10

the substring of NSMutableAttributedString not getting proper

By furkan.vijapura at Nov. 21, 2018, 10:25 a.m. (reply...)

Fixed in iOS11

iOS11 renders the result correctly

By kornerr at Nov. 19, 2018, 2:24 p.m. (reply...)

This also happens with subscript and superscript attributes.

This also happens with Xcode Version 8.3 (8E162) and iOS 10.3 release version.

By koenvanderdrift at April 2, 2017, 3:45 p.m. (reply...)

Added workaround

Workaround for specific scenarios can be found here: http://stackoverflow.com/questions/43074652/ios-10-3-nsstrikethroughstyleattributename-is-not-rendered-if-applied-to-a-sub

By roman.shevtsov at March 28, 2017, 4:12 p.m. (reply...)

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