常用的圆角切角、只切某个角、阴影效果

切view的某个角，左上，左下，右上，右下

- (void)p_addLayer {
    
    //这里设置的是左上和左下角
    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:self.bounds   byRoundingCorners:UIRectCornerBottomLeft |    UIRectCornerBottomRight    cornerRadii:CGSizeMake(30, 30)];
    CAShapeLayer *maskLayer = [[CAShapeLayer alloc] init];
    maskLayer.frame = self.bounds;
    maskLayer.path = maskPath.CGPath;
    self.layer.mask = maskLayer;
}

切四个角，切圆角

    self.layer.borderColor = [UIColor redColor].CGColor;
    self.layer.borderWidth = 1;
    self.layer.masksToBounds = YES;
    self.layer.cornerRadius = 5;

阴影效果

- (UIView *)bgView {
    
    if (!_bgView) {
        _bgView = [[UIView alloc]init];
        _bgView.layer.borderWidth = 1.0;
        _bgView.layer.cornerRadius = 10;
        _bgView.layer.borderColor = [UIColor whiteColor].CGColor;
        _bgView.layer.shadowOpacity = 0.5;// 阴影透明度
        _bgView.layer.shadowColor = RGB(156, 156, 156).CGColor;
        _bgView.layer.shadowRadius = 3;
        _bgView.layer.shadowOffset = CGSizeMake(0.0, 2.0);
        _bgView.backgroundColor = [UIColor whiteColor];
    }
    return _bgView;
}