RoundedUIView.h

//
//  RoundedUIView.h
//  TmpRoundable
//
//  Created by Don Mag on 2/1/17.
//  Copyright © 2017 DonMag. All rights reserved.
//

#import <UIKit/UIKit.h>

IB_DESIGNABLE

@interface RoundedUIView : UIView

@property (nonatomic, assign) IBInspectable CGFloat TopLeftCornerRadius;
@property (nonatomic, assign) IBInspectable CGFloat TopRightCornerRadius;
@property (nonatomic, assign) IBInspectable CGFloat BottomLeftCornerRadius;
@property (nonatomic, assign) IBInspectable CGFloat BottomRightCornerRadius;

@property (nonatomic, assign) IBInspectable BOOL AllCornersTheSame;

@end

RoundedUIView.m

//
//  RoundedUIView.m
//  TmpRoundable
//
//  Created by Don Mag on 2/1/17.
//  Copyright © 2017 DonMag. All rights reserved.
//

#import "RoundedUIView.h"

@interface RoundedUIView()

@property (nonatomic, strong) CAShapeLayer *rLayer;

@end

@implementation RoundedUIView

- (void)setupDefaults {
	if (self.rLayer == nil) {
		self.rLayer = [CAShapeLayer layer];
		self.layer.mask = self.rLayer;
	}
	self.TopLeftCornerRadius = self.TopRightCornerRadius = self.BottomRightCornerRadius = self.BottomLeftCornerRadius = 0.0f;
	self.AllCornersTheSame = YES;
}

- (instancetype)initWithFrame:(CGRect)frame
{
	self = [super initWithFrame:frame];
	if (self) {
		[self setupDefaults];
	}
	return self;
}

- (instancetype)initWithCoder:(NSCoder *)coder
{
	self = [super initWithCoder:coder];
	if (self) {
		[self setupDefaults];
	}
	return self;
}

- (void)layoutSubviews {
	[super layoutSubviews];
	[self updateLayerProperties];
}

- (void)updateLayerProperties {
	
	UIBezierPath *pth = [[UIBezierPath alloc] init];
	CGPoint p = CGPointZero;
	
	CGFloat tl = _TopLeftCornerRadius, tr = _TopRightCornerRadius, br = _BottomRightCornerRadius, bl = _BottomLeftCornerRadius;
	CGFloat w = self.bounds.size.width, h = self.bounds.size.height;
	
	if (_AllCornersTheSame) {
		tl = tr = br = bl = _TopLeftCornerRadius;
	}
	
	p.x = w - tr;
	[pth moveToPoint:p];
	
	p.y = tr;
	[pth addArcWithCenter:p radius:tr startAngle:3 * M_PI_2 endAngle:0 clockwise:YES];
	
	p.x = w;
	p.y = h - br;
	[pth addLineToPoint:p];
	
	p.x = w - br;
	[pth addArcWithCenter:p radius:br startAngle:0 endAngle:M_PI_2 clockwise:YES];
	
	p.x = bl;
	p.y = h;
	[pth addLineToPoint:p];
	
	p.y = h - bl;
	[pth addArcWithCenter:p radius:bl startAngle:M_PI_2 endAngle:2 * M_PI_2 clockwise:YES];
	
	p.x = 0;
	p.y = tl;
	[pth addLineToPoint:p];
	
	p.x = tl;
	[pth addArcWithCenter:p radius:tl startAngle:2 * M_PI_2 endAngle:3 * M_PI_2 clockwise:YES];
	
	[pth closePath];
	
	self.rLayer.path = pth.CGPath;
	
}

- (void)setTopLeftCornerRadius:(CGFloat)TopLeftCornerRadius {
	if (TopLeftCornerRadius != _TopLeftCornerRadius) {
		_TopLeftCornerRadius = TopLeftCornerRadius;
		[self updateLayerProperties];
	}
}

- (void)setTopRightCornerRadius:(CGFloat)TopRightCornerRadius {
	if (TopRightCornerRadius != _TopRightCornerRadius) {
		_TopRightCornerRadius = TopRightCornerRadius;
		[self updateLayerProperties];
	}
}

- (void)setBottomRightCornerRadius:(CGFloat)BottomRightCornerRadius {
	if (BottomRightCornerRadius != _BottomRightCornerRadius) {
		_BottomRightCornerRadius = BottomRightCornerRadius;
		[self updateLayerProperties];
	}
}

- (void)setBottomLeftCornerRadius:(CGFloat)BottomLeftCornerRadius {
	if (BottomLeftCornerRadius != _BottomLeftCornerRadius) {
		_BottomLeftCornerRadius = BottomLeftCornerRadius;
		[self updateLayerProperties];
	}
}

- (void)setAllCornersTheSame:(BOOL)AllCornersTheSame {
	if (AllCornersTheSame != _AllCornersTheSame) {
		_AllCornersTheSame = AllCornersTheSame;
		[self updateLayerProperties];
	}
}

@end