UINvigation,导航条

/*     //单视图控制器的应用     FirstViewController *firstVC = [[FirstViewController alloc] init];     self.window.rootViewController = firstVC;     */    //多视图控制器的应用, 导航控制器, 借助于UINavigationController, 继承于UIViewController, 用于管理具有层级关系(内容)的页面切换    FirstViewController *firstVC = [[FirstViewController alloc] init];    //参数: 导航控制器管理的第一个页面(视图控制器)    UINavigationController *navigation = [[UINavigationController alloc] initWithRootViewController:firstVC];    //指定window的根视图控制器 是 导航控制器    self.window.rootViewController = navigation;    //释放    [firstVC release];    [navigation release];    //导航控制器如何管理视图控制器?    //1.通过栈的形式管理视图控制器    //2.切换到下一个页面, 入栈(push)    //3.返回到上一个页面. 出栈(pop)    //4.展示的栈顶的视图控制器    //5.视图控制器共用的导航栏    //获取,navigationController的navigationBar    //UINavigationBar,导航栏, 继承于UIView    //导航栏的渲染色(涂在最外层)//    navigation.navigationBar.barTintColor = [UIColor greenColor];    //注意: 状态栏, 20 ;导航栏 44; 总共64 ,竖屏44, 横屏32    //导航栏的样式, 会影响状态栏    navigation.navigationBar.barStyle = UIBarStyleDefault;    //半透明, 会影响视图控制器自带的view大小    navigation.navigationBar.translucent = NO;    //导航栏上文字或图片的渲染色    navigation.navigationBar.tintColor = [UIColor magentaColor]; //品红    //UINavigationItem, 控制导航栏上展示的内容    return YES;}//设置下一页, 上一页按钮; 在相应建的视图里面,添加按钮(关联方法); @interface SecondViewController ()@end@implementation SecondViewController- (void)viewDidLoad {    [super viewDidLoad];    // Do any additional setup after loading the view.     NSLog(@"%@",self.navigationController.viewControllers);    self.view.backgroundColor = [UIColor greenColor];    UIButton *nextbutton = [UIButton buttonWithType:UIButtonTypeCustom];    nextbutton.frame = CGRectMake(100, 100, 100, 40);    nextbutton.showsTouchWhenHighlighted = YES;    nextbutton.backgroundColor = [UIColor redColor];    [nextbutton setTitle:@"下一页" forState:UIControlStateNormal];    [nextbutton addTarget:self action:@selector(next) forControlEvents:UIControlEventTouchUpInside];    [self.view addSubview:nextbutton];    UIButton *backButton = [UIButton buttonWithType:UIButtonTypeCustom];    backButton.frame = CGRectMake(100, 200, 100, 40);    backButton.showsTouchWhenHighlighted = YES;    backButton.backgroundColor = [UIColor redColor];    [backButton setTitle:@"上一页" forState:UIControlStateNormal];    [backButton addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];    [self.view addSubview:backButton];    self.navigationItem.title = @"清新绿";}- (void)next {    ThirdViewController *thirdVC = [[ThirdViewController alloc] init];    [self.navigationController pushViewController:thirdVC animated:YES];    [thirdVC release];}- (void)back {    //出栈(数组)    //popToRootViewControllerAnimated,将当前的视图控制器出栈()    [self.navigationController popViewControllerAnimated:YES];    //直接回到第一个页面    [self.navigationController popToRootViewControllerAnimated:YES];    //回到指定页面//    self.navigationController popToViewController: animated:<#(BOOL)#>];}