给UIview添加阴影效果

方法一：对layer进行处理

//添加阴影

- (UIView *)makeShadow:(UIImageView *)view

{

    view.layer.masksToBounds = YES;

    view.layer.cornerRadius = 5;

    view.layer.shadowColor = [UIColor grayColor].CGColor;

    view.layer.shadowOpacity = 0.5;

    view.layer.shadowOffset = CGSizeMake(0, 0.5);

    view.clipsToBounds = NO;

    return view;

}

方法二：添加一个已经处理好的背景图片

    UIImageView* adView = [[UIImageView alloc] initWithFrame:CGRectMake(10, 10, 300, 130)];

    adView.userInteractionEnabled = YES;

    adView.image = [UIImage imageNamed:@"dining3"];

    adView.contentStretch = CGRectMake(0.5, 0.5, 0, 0);