UIView Animation Removes layer.cornerRadius After Completion - ios

Question

I have a UILabel that I am animating the constraints for so that it drop down into view. I am using layer.cornerRadius to give the view rounded corners, but for whatever reason after the animation completes the corner radius is removed.
[UIView animateWithDuration:0.3 delay:0 usingSpringWithDamping:0.7 initialSpringVelocity:0.4 options:UIViewAnimationOptionCurveEaseInOut animations:^{
if (shouldShow) {
self.labelOverMapTopConstraint.constant = 16;
} else {
self.labelOverMapTopConstraint.constant = -40;
}
[self.view layoutIfNeeded];
} completion:nil];
cornerRadius is set in viewDidLoad.
Is there a way to prevent this from happening?

Answer 1

I suspect you're subclassing UILabel here since it looks like you have padding in there, is that correct?
There could be something going awry with any custom drawing/calculations you're doing in there, so it would probably be helpful to post that code for inspection as well.
A few questions:
Do you have masksToBounds set to YES?
If you're not using a custom UILabel subclass, are you wrapping the label in a view?
How is the animation being triggered? Is it by a button? A callback from a NSURLRequest? If it's triggered by an async callback are you jumping back on the main queue to perform the animation?
If the animation is triggered automatically within the lifecycle, which lifecycle method is it triggered in?
I wasn't able to reproduce the issue in a test project with a vanilla UILabel. I then tried it with a UILabel subclass which includes additional padding and still wasn't able to reproduce it there.
I've included example code snippets below:
#import "ViewController.h"
#import "R4NInsetLabel.h"
#interface ViewController ()
#property BOOL showingToast;
#property (strong, nullable) IBOutlet R4NInsetLabel *toastLabel;
#property (strong, nullable) IBOutlet NSLayoutConstraint *toastLabelTopConstraint;
#end
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.navigationController.navigationBar.titleTextAttributes = #{NSForegroundColorAttributeName : [UIColor whiteColor]};
self.showingToast = NO;
// start with the label pushed off the top of the screen
self.toastLabelTopConstraint.constant = -40.0f;
self.toastLabel.layer.cornerRadius = 6.0f;
self.toastLabel.layer.masksToBounds = YES;
}
- (IBAction)toggleToast:(id)sender {
[UIView animateWithDuration:0.3 delay:0 usingSpringWithDamping:0.7 initialSpringVelocity:0.4 options:UIViewAnimationOptionCurveEaseInOut animations:^{
if (self.showingToast == NO) {
self.toastLabelTopConstraint.constant = 16;
self.showingToast = YES;
} else {
self.toastLabelTopConstraint.constant = -40;
self.showingToast = NO;
}
[self.view layoutIfNeeded];
} completion:nil];
}
#end
#import "R4NInsetLabel.h"
IB_DESIGNABLE
#interface R4NInsetLabel()
#property IBInspectable CGFloat contentPadding;
#property (nonatomic) UIEdgeInsets contentInsets;
- (CGSize)_addInsetsToSize:(CGSize)size;
#end
#implementation R4NInsetLabel
- (UIEdgeInsets)contentInsets {
return UIEdgeInsetsMake(self.contentPadding, self.contentPadding, self.contentPadding, self.contentPadding);
}
- (CGSize)_addInsetsToSize:(CGSize)size {
CGFloat width = size.width + self.contentInsets.left + self.contentInsets.right;
CGFloat height = size.height + self.contentInsets.top + self.contentInsets.bottom;
return CGSizeMake(width, height);
}
- (void)drawTextInRect:(CGRect)rect {
CGRect insetRect = UIEdgeInsetsInsetRect(rect, self.contentInsets);
[super drawTextInRect:insetRect];
}
- (CGSize)intrinsicContentSize {
CGSize baseSize = [super intrinsicContentSize];
return [self _addInsetsToSize:baseSize];
}
- (CGSize)sizeThatFits:(CGSize)size {
CGSize baseSize = [super sizeThatFits:size];
return [self _addInsetsToSize:baseSize];
}
#end
And here's what it looks like:

Answer 2

You also need to set the corner radius on viewDidLayoutSubviews
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
label.layer.cornerRadius = yourValue
}