使用纯代码实现一个导航栏的效果。单击按钮并且产生事件。基本思路是:
1.创建一个导航栏(UINavigationBar对象)
2.创建一个导航栏集合(UINavigationItem对象)
3.创建一个左边按钮、一个右边按钮(UIBarButtonItem对象),并实现对应的事件方法
具体的实现代码如下:
ViewController.h文件
#import <UIKit/UIKit.h> @interface ViewController : UIViewController @end
ViewController.m文件中的代码:
@interface ViewController () @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. //创建一个导航栏 UINavigationBar *navBar = [[UINavigationBar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)]; //创建一个导航栏集合 UINavigationItem *navItem = [[UINavigationItem alloc] initWithTitle:nil]; //在这个集合Item中添加标题,按钮 //style:设置按钮的风格,一共有三种选择 //action:@selector:设置按钮的点击事件 //创建一个左边按钮 UIBarButtonItem *leftButton = [[UIBarButtonItem alloc] initWithTitle:@"左边" style:UIBarButtonItemStyleBordered target:self action:@selector(clickLeftButton)]; //创建一个右边按钮 UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithTitle:@"右边" style:UIBarButtonItemStyleDone target:self action:@selector(clickRightButton)]; //设置导航栏的内容 [navItem setTitle:@"凌凌漆"]; //把导航栏集合添加到导航栏中,设置动画关闭 [navBar pushNavigationItem:navItem animated:NO]; //把左右两个按钮添加到导航栏集合中去 [navItem setLeftBarButtonItem:leftButton]; [navItem setRightBarButtonItem:rightButton]; //将标题栏中的内容全部添加到主视图当中 [self.view addSubview:navBar]; //最后将控件在内存中释放掉,以避免内存泄露 [navItem release]; [leftButton release]; [rightButton release]; } -(void)showDialog:(NSString *)str { UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"这是一个对话框" message:str delegate:self cancelButtonTitle:@"确定" otherButtonTitles: nil]; [alert show]; [alert release]; } -(void) clickLeftButton { [self showDialog:@"点击了导航栏左边按钮"]; } -(void) clickRightButton { [self showDialog:@"点击了导航栏右边按钮"]; } - (void)viewDidUnload { [super viewDidUnload]; // Release any retained subviews of the main view. } - (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation { return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown); } @end