IOS导航栏的使用

导航栏包含导航控制器的导航的按钮。在导航栏中的标题是当前视图控制器的标题。


示例代码和步骤

1.创视图应用程序

2. 现在，选择应用程序 Delegate.h ，添加导航控制器的属性，如下所示:

#import <UIKit/UIKit.h>

@class ViewController;

@interface AppDelegate : UIResponder <UIApplicationDelegate>

@property (strong, nonatomic) UIWindow *window;

@property (strong, nonatomic) ViewController *viewController;

@property (strong, nonatomic) UINavigationController *navController;

@end

3. 更新应用程序: didFinishLaunchingWithOptions:方法，在AppDelegate.m文件分配的导航控制器，并使其成为窗口的根视图控制器，如下所示：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:
    [[UIScreen mainScreen] bounds]];
    // Override point for customization after application launch.
    self.viewController = [[ViewController alloc] 
    initWithNibName:@"ViewController" bundle:nil];
    //Navigation controller init with ViewController as root
    UINavigationController *navController = [[UINavigationController alloc]
    initWithRootViewController:self.viewController];
    self.window.rootViewController = navController;
    [self.window makeKeyAndVisible];
    return YES;
}

4.现在，通过选择File -> New ->File... -> Objective C Class 添加新的类文件TempViewController，然后将类命名 TempViewController 与 UIViewController 的子类。

5.在ViewController.h中添加navButon，如下所示

// ViewController.h
#import <UIKit/UIKit.h>

@interface ViewController : UIViewController
{    
    UIButton *navButton;
}
@end

6.现在添加方法addNavigationBarItem并在viewDidLoad调用方法

7. 为导航项创建方法

8. 我们还需要创建另一种方法到另一视图控制器 TempViewController。

9. 更新后的ViewController.m，如下所示:

// ViewController.m
#import "ViewController.h"
#import "TempViewController.h"
@interface ViewController ()

@end
@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self addNavigationBarButton];
    //Do any additional setup after loading the view, typically from a nib
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

-(IBAction)pushNewView:(id)sender{
   TempViewController *tempVC =[[TempViewController alloc]
   initWithNibName:@"TempViewController" bundle:nil];
   [self.navigationController pushViewController:tempVC animated:YES];
}

-(IBAction)myButtonClicked:(id)sender{
   // toggle hidden state for navButton
   [navButton setHidden:!nav.hidden];
}

-(void)addNavigationBarButton{
   UIBarButtonItem *myNavBtn = [[UIBarButtonItem alloc] initWithTitle:
   @"MyButton" style:UIBarButtonItemStyleBordered target:
   self action:@selector(myButtonClicked:)];
   
   [self.navigationController.navigationBar setBarStyle:UIBarStyleBlack];
   [self.navigationItem setRightBarButtonItem:myNavBtn];
   
   // create a navigation push button that is initially hidden
   navButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
   [navButton setFrame:CGRectMake(60, 50, 200, 40)];
   [navButton setTitle:@"Push Navigation" forState:UIControlStateNormal];
   [navButton addTarget:self action:@selector(pushNewView:) 
   forControlEvents:UIControlEventTouchUpInside];
   [self.view addSubview:navButton];
   [navButton setHidden:YES];
}
@end

10. 现在当我们运行应用程序时我们就会得到下面的输出

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11. 单击 MyButton 导航按钮，切换导航按钮可见性

12. 单击导航按钮，显示另一个视图控制器，如下所示

iOS Tutorial