UIView animation with CABasicAnimation - border width and color

Animate-Border-Width-And-Color.m

static const CGFloat kCornerRadiusStateNormal = 20.0f;
static const CGFloat kCornerRadiusStateSelected = 40.0f;
static const CGFloat kBorderWidth = 3.0f;

// First variant, long and ugly
- (void)updateStateAnimated:(BOOL)animated {
  if (animated) {
    
    CAMediaTimingFunction* timing =[[CAMediaTimingFunction alloc] initWithControlPoints:0.2f:0.0f:0.0f:1.0f];

    [CATransaction begin];
    [CATransaction setAnimationDuration:kAnimationDuration];
    [CATransaction setAnimationTimingFunction:timing];

    CGFloat fromCornerRadius = self.isSelected ? kCornerRadiusStateNormal : kCornerRadiusStateSelected;
    CGFloat toCornerRadius = self.isSelected ? kCornerRadiusStateSelected : kCornerRadiusStateNormal;
    CABasicAnimation* cornerRadiusAnimation = [CABasicAnimation animationWithKeyPath:@"cornerRadius"];
    cornerRadiusAnimation.removedOnCompletion = NO;
    cornerRadiusAnimation.timingFunction = timing;
    cornerRadiusAnimation.fromValue = [NSNumber numberWithFloat:fromCornerRadius];
    cornerRadiusAnimation.toValue = [NSNumber numberWithFloat:toCornerRadius];
    cornerRadiusAnimation.duration = kAnimationDuration;

    CGFloat fromBorderWidth = self.isSelected ? kBorderWidth : 0;
    CGFloat toBorderWidth = self.isSelected ? 0 : kBorderWidth;
    CABasicAnimation* borderWidthAnimation =  [CABasicAnimation animationWithKeyPath:@"borderWidth"];
    borderWidthAnimation.removedOnCompletion = NO;
    borderWidthAnimation.timingFunction = timing;
    borderWidthAnimation.fromValue = [NSNumber numberWithFloat:fromBorderWidth];
    borderWidthAnimation.toValue = [NSNumber numberWithFloat:toBorderWidth];
    borderWidthAnimation.duration = kAnimationDuration;

    CAAnimationGroup *group = [[CAAnimationGroup alloc] init];
    group.animations = @[ cornerRadiusAnimation, borderWidthAnimation];
    group.duration = kAnimationDuration;
    group.beginTime = 0.0f;

    __weak __typeof__(self) weakSelf = self;
    [CATransaction setCompletionBlock:^{
      weakSelf.layer.borderWidth = toBorderWidth;
      weakSelf.layer.cornerRadius = toCornerRadius;
    }];

    [self.layer addAnimation:group forKey:@"tileAnimation"];

    [CATransaction commit];

  } else {

    self.layer.cornerRadius = self.isSelected ? kCornerRadiusStateSelected : kCornerRadiusStateNormal;
    self.layer.borderWidth = self.isSelected ? 0 : kBorderWidth;
  }

}

// Second variant, short and sexy
- (void)updateStateAnimated:(BOOL)animated {
  __weak __typeof__(self) weakSelf = self;
  void (^animationsBlock)(void) = ^{
    weakSelf.layer.cornerRadius =
        weakSelf.isSelected ? kCornerRadiusStateSelected : kCornerRadiusStateNormal;

    weakSelf.layer.borderWidth =
        [weakSelf isBorderHiddenForState:weakSelf.state] ? 0 : kBorderWidth;
  };

  if (!animated) {
    animationsBlock();
    return;
  }

  [CATransaction begin];
  [CATransaction setAnimationDuration:kCornerRadiusAnimationDuration];

  CAMediaTimingFunction *timingFunction =
      [[CAMediaTimingFunction alloc] initWithControlPoints:0.2f:0.0f:0.0f:1.0f];
  [CATransaction setAnimationTimingFunction:timingFunction];

  [UIView animateWithDuration:kCornerRadiusAnimationDuration animations:animationsBlock];

  [CATransaction commit];
}

Animate-Border-Width-And-Color.swift

func updateOutline(isShowing: Bool, animated: Bool) {
    let toColor: UIColor = isShowing ? .systemBlue : .clear
    let toWidth: CGFloat = isShowing ? 2 : 0
    let animationDuration = 0.2

    if animated {
        let borderColorAnimation: CABasicAnimation = CABasicAnimation(keyPath: "borderColor")
        borderColorAnimation.fromValue = layer.borderColor
        borderColorAnimation.toValue = toColor.cgColor
        borderColorAnimation.duration = animationDuration
        layer.add(borderColorAnimation, forKey: "borderColor")
        layer.borderColor = toColor.cgColor

        let borderWidthAnimation: CABasicAnimation = CABasicAnimation(keyPath: "borderWidth")
        borderWidthAnimation.fromValue = layer.borderWidth
        borderWidthAnimation.toValue = toWidth
        borderWidthAnimation.duration = animationDuration
        layer.add(borderWidthAnimation, forKey: "borderWidth")
        layer.borderWidth = toWidth
    } else {
        layer.borderColor = toColor.cgColor
        layer.borderWidth = toWidth
    }
}