UISearchBar 设置背景色，去掉黑线

    self.searchBar = [[UISearchBar
alloc]initWithFrame:CGRectMake(0,
5, self.view.bounds.size.width,
35)];

    self.searchBar.delegate =
self;

    //设置背景色

    self.searchBar.barTintColor
= [UIColor
colorWithRed:239/255.0
green:240/255.0
blue:244/255.0
alpha:1.0];

    //设置右边的取消按钮

        for (id obj
in [self.searchBar
subviews]) {

            if ([obj
isKindOfClass:[UIView
class]]) {

                for (id obj2
in [obj subviews]) {

                    if ([obj2
isKindOfClass:[UIButton
class]]) {

                        UIButton *btn = (UIButton *)obj2;

                        [btn setTitle:@"取消"
forState:UIControlStateNormal];

                    }

                }

            }

        }

    [self.searchBar
setBackgroundImage:[UIImage
new]]; //去掉多余的黑线

    

    [self.view
addSubview:self.searchBar];