-(void) setBar{    UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:nil];        UIBarButtonItem *searchButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemSearch target:self action:nil];        self.navigationItem.leftBarButtonItems = @[addButton, searchButton];        UIBarButtonItem *organizeButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemOrganize target:self action:nil];        [self setToolbarItems:@[organizeButton]];}-(void) showBar{    // 无论哪套设置方法都可以这么判断是否隐藏    if (self.navigationController.navigationBar.hidden)    {        NSLog(@"show it");                // 两套隐藏方法，这套无动画，不可混用        //self.navigationController.navigationBar.hidden = NO;        //self.navigationController.toolbar.hidden = NO;                // 有动画        [self.navigationController setNavigationBarHidden:NO animated:YES];        [self.navigationController setToolbarHidden:NO animated:YES];            }    else    {        NSLog(@"hide it");        [self.navigationController setNavigationBarHidden:YES animated:YES];        [self.navigationController setToolbarHidden:YES animated:YES];    }}- (void)viewDidLoad{    [super viewDidLoad];    // Do any additional setup after loading the view.        [self setBar];    }-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{    [self showBar];}