在按钮单击处添加此文件=〉.m文件：

UISearchBar  *sBar = [[UISearchBar alloc]initWithFrame:CGRectMake(0,10,self.navigationController.navigationBar.bounds.size.width,self.navigationController.navigationBar.bounds.size.height/2)];
sBar.delegate = self;
[self.navigationController.navigationBar addSubview:sBar];

并添加此=〉.h文件

@interface ViewController : UIViewController<UISearchBarDelegate>

要使搜索栏像这样你要插入按钮在导航栏控制器和设置为search.png的背景图像（你的形象）.所以，当用户点击这个按钮设置为searchbar的目标将被打开.请检查下面的代码为您的参考.
首先在.h文件中设置委托方法。

@interface FriendsViewController : UIViewController <UISearchDisplayDelegate,UISearchBarDelegate,UIAlertViewDelegate>
 @property (nonatomic, strong) UIButton *searchButton;
 @property (nonatomic, strong) UIBarButtonItem *searchItem;
 @property (nonatomic, strong) UISearchBar *searchBar;
 @property (strong, nonatomic) UISearchController *searchController;
 @property (strong, nonatomic) UISearchDisplayController *d1;

然后在导航栏中插入按钮。

- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
UIButton *btn=[[UIButton alloc]initWithFrame:CGRectMake(279,9,25, 25)];
[btn setImage:[UIImage imageNamed:@"search"] //put here your searchimage
forState:UIControlStateNormal];
[btn setTitle:@"" forState:UIControlStateNormal];
[btn addTarget:self action:@selector(clickme:) forControlEvents:UIControlEventTouchUpInside];
UIBarButtonItem *barbtn=[[UIBarButtonItem alloc]initWithCustomView:btn];
self.tabBarController.navigationItem.rightBarButtonItem=barbtn;
[self.tabBarController.navigationController.navigationBar setHidden:NO];

现在你必须在clickme上设置searchcontroller你的按钮方法。

- (IBAction)clickme:(id)sender{
UISearchBar *searchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, 300, 44.0)];
searchBar.autoresizingMask =0;
searchBar.delegate = self;
searchBar.placeholder = @"Search for items...";
searchBar.showsScopeBar=YES;

UIView *searchBarWrapper = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 200, 44)];
searchBarWrapper.autoresizingMask = 0;
[searchBarWrapper addSubview:searchBar];

self.searchItem = [[UIBarButtonItem alloc] initWithCustomView:searchBarWrapper];
self.tabBarController.navigationItem.leftBarButtonItem = self.searchItem;

self.navigationItem.rightBarButtonItem = nil;
self.navigationItem.titleView = nil;

  ////////////// ~ Search Display Controller as Object ~/////////////////////////////

self.d1 = [[UISearchDisplayController alloc] initWithSearchBar:searchBar contentsController:self];
self.d1.delegate = self;
self.d1.searchResultsDataSource = self;
self.d1.searchResultsDelegate = self;
self.d1.searchResultsTableView.rowHeight = 40;
self.d1.displaysSearchBarInNavigationBar = YES;
self.searchBar.translucent = NO;
self.searchBar.barTintColor = [UIColor grayColor];
self.d1.searchBar.tintColor = [UIColor blueColor];

[searchBar sizeToFit];

}

当你点击搜索图标

对于搜索按钮，如果需要，可以使用UIBarButtonSystemItemSearch。

self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]
                               initWithBarButtonSystemItem:UIBarButtonSystemItemSearch
                               target:self
                               action:@selector(actionSearch:)];

并且你可以设置搜索栏为导航栏的标题视图

self.navigationItem.titleView = mySearchBar;