这也是困扰我的问题之一。目前我想出了 不用 AutoLayout时的解决办法：如果用xib的话，请见 http://blog.csdn.net/rhljiayou/article/details/12029927 ；如果不是用xib的话，只能手动偏移了。

 #define IOS_7 ([[[UIDevice currentDevice] systemVersion] floatValue] >= 7.0f)
#define IOS6_7_DELTA(V,X,Y,W,H) if (IOS_7) {CGRect f = V.frame;f.origin.x += X;f.origin.y += Y;f.size.width += W;f.size.height += H;V.frame=f;}
...
IOS6_7_DELTA(view, 0, 20, 60, 0);

另外，如果使用了AutoLayout，并且用了StoryBoard，那么可以很方便地将搜索框跟TopLayoutGuide做一个constraint。这个TopLayoutGuide看起来是很有用的，可以看到官方文档里面说的用法。

• If a status bar is visible onscreen and there is no visible navigation bar, the bottom of the status bar
• If a navigation bar is visible onscreen, the bottom of the navigation bar
• If there is no status bar or navigation bar visible onscreen, the top of the screen in the device’s current orientation

但是如果只是用xib的话，似乎没法在IB里面加这个constraint（这个问题见我在stackoverflow上问的 问题 ，但是目前没有解答【大概我的英文太差了？】）。如果是纯代码的话，我对constraints语法不是很熟悉，写的估计是错的，仅供参考：

 - (void)viewDidLoad
{
    [super viewDidLoad];
    NSString *verticalConstraint = @"V:|[v]";// for iOS6
    NSMutableDictionary *views = [NSMutableDictionary new];
    NSMutableArray *constraints = [NSMutableArray new];
    [views setObject:self.subview forKey:@"v"];
    if ([self respondsToSelector:@selector(topLayoutGuide)]) {
        // for iOS7
        [views setObject:self.topLayoutGuide forKey:@"topLayoutGuide"];
        verticalConstraint = @"V:[topLayoutGuide][v]";
    }
    [constraints addObjectsFromArray:[NSLayoutConstraint constraintsWithVisualFormat:verticalConstraint options:0 metrics:nil views:views]];
    // ... other constraints
    [self.view addConstraints:constraints];
    // Do any additional setup after loading the view from its nib.
}