Subclassed UISegmentedControl titleTextAttributes not always applied - ios

Question

Scenario
I have a peculiar bug in my subclassed UISegmentedControl. What I have simply done is subclassed a UISegmentedControl to remove the default indicators of selection/deselection and used a custom CALayer as an indicator for the same. At the same time, I have modified the titleTextAttributes to complement the UI.
Problem
When the view first appears and default selected index is 0, it looks like this:
When I try to change the selectedSegmentIndex to 1 it becomes:
Where it should look like this (corrected once you change the selectedSegmentIndex a few times):
This behaviour of titleTextAttributes not changing is random, however 2 cases when this happens 100% of the time are:
View appears, and you select segment at index 1
Select last segment, and then select segment 0
I have not found subclassing notes in the UISegmentedControl official docs.
Sample project HERE.
NOTE: If you use only 2 segments, you will never the see the title of the segment at index 1 on selection.

Answer 1

Indeed it's a weird behavior.
You can workaround it adding an explicit call to [self setNeedsLayout] after changing the indication layer frame.
//
// RBLSegmentedControl.m
// Rabbler
//
// Created by Utkarsh Singh on 05/11/15.
// Copyright © 2015 Neeraj SIngh. All rights reserved.
//
#import "NPSegmentedControl.h"
#interface NPSegmentedControl ()
#property (nonatomic, retain) CALayer* selectedIndicationLayer;
#end
#implementation NPSegmentedControl
- (instancetype)initWithItems:(NSArray *)items {
if (self = [super initWithItems:items]) {
self.selectedIndicationLayer.frame = CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width / items.count, self.frame.size.height);
[self addTarget:self action:#selector(segmentedControlDidChange) forControlEvents:UIControlEventValueChanged];
NSDictionary* selectedAttributes = #{NSFontAttributeName:[UIFont fontWithName:#"HelveticaNeue-Light" size:15],
NSForegroundColorAttributeName:[UIColor whiteColor]};
NSDictionary* deselectedAttributes = #{NSFontAttributeName:[UIFont fontWithName:#"HelveticaNeue-Light" size:15],
NSForegroundColorAttributeName:[UIColor redColor]};
NSDictionary* highlightedAttributes = #{NSFontAttributeName:[UIFont fontWithName:#"HelveticaNeue-Light" size:15],
NSForegroundColorAttributeName:[[UIColor redColor] colorWithAlphaComponent:0.6f]};
[self setTitleTextAttributes:deselectedAttributes forState:UIControlStateNormal];
[self setTitleTextAttributes:selectedAttributes forState:UIControlStateSelected];
[self setTitleTextAttributes:highlightedAttributes forState:UIControlStateHighlighted];
}
return self;
}
- (void) segmentedControlDidChange {
[self animateSegmentSelectionChange];
if (self.delegate && [self.delegate respondsToSelector:#selector(segmentedControlDidChangeSelectedSegment:)]) {
[self.delegate segmentedControlDidChangeSelectedSegment:self.selectedSegmentIndex];
}
}
- (void) animateSegmentSelectionChange {
[UIView animateWithDuration:0.25
delay:0
options:(UIViewAnimationOptionCurveEaseInOut | UIViewAnimationOptionBeginFromCurrentState)
animations:^{
CGRect frame = self.selectedIndicationLayer.frame;
frame.origin.x = self.selectedSegmentIndex * [UIScreen mainScreen].bounds.size.width / self.numberOfSegments;
self.selectedIndicationLayer.frame = frame;
[self setNeedsLayout]; // <--
} completion:nil];
}
- (CALayer *) selectedIndicationLayer {
if (!_selectedIndicationLayer) {
_selectedIndicationLayer = [CALayer layer];
_selectedIndicationLayer.backgroundColor = [[UIColor redColor] CGColor];
_selectedIndicationLayer.cornerRadius = self.frame.size.height /2;
_selectedIndicationLayer.borderColor = [UIColor whiteColor].CGColor;
_selectedIndicationLayer.borderWidth = 1.5f;
[self.layer insertSublayer:_selectedIndicationLayer atIndex:0];
}
return _selectedIndicationLayer;
}
- (void) setSelectedSegmentIndex:(NSInteger)selectedSegmentIndex {
[super setSelectedSegmentIndex:selectedSegmentIndex];
[self animateSegmentSelectionChange];
}
- (void) setIndicatorColor:(UIColor *)indicatorColor {
self.selectedIndicationLayer.backgroundColor = indicatorColor.CGColor;
}
#end

Answer 2

I change your selectedIndicationLayer to this and it fix the problem
- (CALayer *) selectedIndicationLayer {
if (!_selectedIndicationLayer) {
_selectedIndicationLayer = [CALayer layer];
_selectedIndicationLayer.backgroundColor = [[UIColor redColor] CGColor];
_selectedIndicationLayer.cornerRadius = self.frame.size.height /2;
_selectedIndicationLayer.borderColor = [UIColor whiteColor].CGColor;
_selectedIndicationLayer.borderWidth = 1.5f;
}
if ([self.layer.sublayers containsObject:_selectedIndicationLayer]) {
[_selectedIndicationLayer removeFromSuperlayer];
}
[self.layer insertSublayer:_selectedIndicationLayer atIndex:0];
return _selectedIndicationLayer;
}

Answer 3

Just edit your following method.
- (CALayer *) selectedIndicationLayer {
if (!_selectedIndicationLayer) {
_selectedIndicationLayer = [CALayer layer];
_selectedIndicationLayer.backgroundColor = [[UIColor redColor] CGColor];
_selectedIndicationLayer.cornerRadius = self.frame.size.height /2;
_selectedIndicationLayer.borderColor = [UIColor whiteColor].CGColor;
_selectedIndicationLayer.borderWidth = 1.5f;
}
[self.layer insertSublayer:_selectedIndicationLayer atIndex:0];
return _selectedIndicationLayer;
}