Add edge borders to UIView with autolayout, inspired from https://stackoverflow.com/a/23157272/1677041

UIView+EdgeBorder.h

//
//  UIView+EdgeBorder.h
//  DSUtility
//
//  Created by WeiHan on 6/6/17.
//  Copyright © 2017 WeiHan. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UIView (EdgeBorder)

- (void)setEdgeBorder:(UIRectEdge)option color:(UIColor *)color;

- (void)setEdgeBorder:(UIRectEdge)option color:(UIColor *)color thickness:(CGFloat)thickness;

- (void)setEdgeBorder:(UIRectEdge)option color:(UIColor *)color thickness:(CGFloat)thickness configuration:(void (^)(UIRectEdge option, UIView *border))block;

@end

UIView+EdgeBorder.m

//
//  UIView+EdgeBorder.m
//  DSUtility
//
//  Created by WeiHan on 6/6/17.
//  Copyright © 2017 WeiHan. All rights reserved.
//
//  Inspired from https://stackoverflow.com/a/23157272/1677041
//

#import "UIView+EdgeBorder.h"

@implementation UIView (EdgeBorder)

- (void)setEdgeBorder:(UIRectEdge)option color:(UIColor *)color
{
    [self setEdgeBorder:option color:color thickness:1.0];
}

- (void)setEdgeBorder:(UIRectEdge)option color:(UIColor *)color thickness:(CGFloat)thickness
{
    [self setEdgeBorder:option color:color thickness:thickness configuration:nil];
}

- (void)setEdgeBorder:(UIRectEdge)option color:(UIColor *)color thickness:(CGFloat)thickness configuration:(void (^)(UIRectEdge option, UIView *border))block
{
#define EdgeConstraint(__attribute__, __view__)      [NSLayoutConstraint constraintWithItem: __view__ attribute: __attribute__ relatedBy: NSLayoutRelationEqual toItem: self attribute: __attribute__ multiplier: 1.0 constant : 0]

#define WidthConstraint(__const_height__, __view__)  [NSLayoutConstraint constraintWithItem: __view__ attribute: NSLayoutAttributeWidth relatedBy: NSLayoutRelationEqual toItem: self attribute: NSLayoutAttributeWidth multiplier : 0 constant: __const_height__]

#define HeightConstraint(__const_height__, __view__) [NSLayoutConstraint constraintWithItem:__view__ attribute: NSLayoutAttributeHeight relatedBy: NSLayoutRelationEqual toItem: self attribute: NSLayoutAttributeHeight multiplier : 0 constant: __const_height__]

    UIView * (^ createBorder)(UIRectEdge) = ^UIView *(UIRectEdge op) {
        UIView *border = [UIView new];

        border.translatesAutoresizingMaskIntoConstraints = NO;
        border.backgroundColor = color;
        !block ? : block(op, border);
        [self addSubview:border];
        return border;
    };

    if (option & UIRectEdgeTop) {
        UIView *view = createBorder(UIRectEdgeLeft);

        [self addConstraint:EdgeConstraint(NSLayoutAttributeTop, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeLeft, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeRight, view)];
        [self addConstraint:HeightConstraint(thickness, view)];
    }

    if (option & UIRectEdgeLeft) {
        UIView *view = createBorder(UIRectEdgeLeft);

        [self addConstraint:EdgeConstraint(NSLayoutAttributeTop, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeLeft, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeBottom, view)];
        [self addConstraint:WidthConstraint(thickness, view)];
    }

    if (option & UIRectEdgeBottom) {
        UIView *view = createBorder(UIRectEdgeBottom);

        [self addConstraint:EdgeConstraint(NSLayoutAttributeLeft, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeRight, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeBottom, view)];
        [self addConstraint:HeightConstraint(thickness, view)];
    }

    if (option & UIRectEdgeRight) {
        UIView *view = createBorder(UIRectEdgeRight);

        [self addConstraint:EdgeConstraint(NSLayoutAttributeTop, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeRight, view)];
        [self addConstraint:EdgeConstraint(NSLayoutAttributeBottom, view)];
        [self addConstraint:WidthConstraint(thickness, view)];
    }
}

@end