iOS如何将UIView单独切角

  UIRectCornerTopLeft = 1 << 0,  (左上)

    UIRectCornerTopRight    = 1 << 1,  (右上)

    UIRectCornerBottomLeft  = 1 << 2,  (左下)

    UIRectCornerBottomRight = 1 << 3,  (右下)

    UIRectCornerAllCorners  = ~0UL

UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:self.BID.bounds byRoundingCorners:UIRectCornerBottomRight cornerRadii:CGSizeMake(10*YZAdapter, 0)];

        CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];

        maskLayer.frame = self.BID.bounds;

        maskLayer.path = maskPath.CGPath;

        self.BID.layer.mask = maskLayer;