利用图层的mask属性裁剪图形

需求如上图。

代码如下

//充值
        UIButton *rechargeButton = [[UIButton alloc] initWithFrame:CGRectMake(20, 10, 80, 30)];
        [rechargeButton setTitle:@"充值" forState:UIControlStateNormal];
        [rechargeButton.titleLabel setFont:[UIFont systemFontOfSize:13]];
        rechargeButton.backgroundColor = rgb(11, 157, 224);
        [bottomView addSubview:rechargeButton];
        CAShapeLayer *maskLayer = [CAShapeLayer layer];
        CGRect rect = rechargeButton.bounds;
        CGSize radii = CGSizeMake(15, 15);
        UIRectCorner corners = UIRectCornerTopLeft | UIRectCornerBottomLeft;
        UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:rect byRoundingCorners:corners cornerRadii:radii];
        maskLayer.path = path.CGPath;
        rechargeButton.layer.mask = maskLayer;

这样我们就可以根据路径，来裁剪到我们想要的形状。