iOS 实现半边圆角或部分圆角

#import <UIKit/UIKit.h>
@interface UIView (LSCore)

#pragma mark - 设置部分圆角
/**
 *  设置部分圆角(绝对布局)
 *
 *  @param corners 需要设置为圆角的角 UIRectCornerTopLeft | UIRectCornerTopRight | UIRectCornerBottomLeft | UIRectCornerBottomRight | UIRectCornerAllCorners
 *  @param radii   需要设置的圆角大小 例如 CGSizeMake(20.0f, 20.0f)
 */
- (void)addRoundedCorners:(UIRectCorner)corners
                withRadii:(CGSize)radii;
/**
 *  设置部分圆角(相对布局)
 *
 *  @param corners 需要设置为圆角的角 UIRectCornerTopLeft | UIRectCornerTopRight | UIRectCornerBottomLeft | UIRectCornerBottomRight | UIRectCornerAllCorners
 *  @param radii   需要设置的圆角大小 例如 CGSizeMake(20.0f, 20.0f)
 *  @param rect    需要设置的圆角view的rect
 */
- (void)addRoundedCorners:(UIRectCorner)corners
                withRadii:(CGSize)radii
                 viewRect:(CGRect)rect;

@end



#import "UIView+LSCore.h"
@implementation UIView (LSCore)
#pragma mark - 设置部分圆角
/**
 *  设置部分圆角(绝对布局)
 *
 *  @param corners 需要设置为圆角的角 UIRectCornerTopLeft | UIRectCornerTopRight | UIRectCornerBottomLeft | UIRectCornerBottomRight | UIRectCornerAllCorners
 *  @param radii   需要设置的圆角大小 例如 CGSizeMake(20.0f, 20.0f)
 */
- (void)addRoundedCorners:(UIRectCorner)corners
                withRadii:(CGSize)radii {

    UIBezierPath* rounded = [UIBezierPath bezierPathWithRoundedRect:self.bounds byRoundingCorners:corners cornerRadii:radii];
    CAShapeLayer* shape = [[CAShapeLayer alloc] init];
    [shape setPath:rounded.CGPath];

    self.layer.mask = shape;
}

/**
 *  设置部分圆角(相对布局)
 *
 *  @param corners 需要设置为圆角的角 UIRectCornerTopLeft | UIRectCornerTopRight | UIRectCornerBottomLeft | UIRectCornerBottomRight | UIRectCornerAllCorners
 *  @param radii   需要设置的圆角大小 例如 CGSizeMake(20.0f, 20.0f)
 *  @param rect    需要设置的圆角view的rect
 */
- (void)addRoundedCorners:(UIRectCorner)corners
                withRadii:(CGSize)radii
                 viewRect:(CGRect)rect {

    UIBezierPath* rounded = [UIBezierPath bezierPathWithRoundedRect:rect byRoundingCorners:corners cornerRadii:radii];
    CAShapeLayer* shape = [[CAShapeLayer alloc] init];
    [shape setPath:rounded.CGPath];

    self.layer.mask = shape;
}
@end

- (UIImageView *)blackBGimageView {

    if (!_blackBGimageView) {

        _blackBGimageView = [[UIImageView alloc] init];
        _blackBGimageView.backgroundColor = black_color;
        _blackBGimageView.alpha = 0.7;
        [_blackBGimageView addRoundedCorners:UIRectCornerBottomLeft|UIRectCornerBottomRight  withRadii:CGSizeMake(5.0, 5.0) viewRect:CGRectMake(0, 0, ((SCREEN_WIDTH - 4*10)/2.0), 35)];
    }

    return _blackBGimageView;
}