ios初学者之在真机上调试应用程序

//
// ViewController.m
// UINavigationbar
//

#import "ViewController.h"&＃64;interface ViewController ()&＃64;end&＃64;implementation ViewController
//
UINavigationBar *navigationBar;NSInteger count;- (void)viewDidLoad {[super viewDidLoad];// Do any additional setup after loading the view, typically from a nib.
navigationBar &＃61; [[UINavigationBar alloc]initWithFrame:CGRectMake(0, 20, self.view.bounds.size.width, 50)];
// navigationBar.backgroundColor &＃61; [UIColor grayColor];
[self.view addSubview:navigationBar];//给navigationBar添加一个navigationItem&＃xff1b;
[self push];}
//navigationBar好比一个栈容器
-(void)push{
// 入栈
[navigationBar pushNavigationItem:[self makeNavItem] animated:YES];count&＃43;&＃43;;}
//出栈
-(void)pop{if (count > 1) {count --;[navigationBar popNavigationItemAnimated:YES];}else{UIAlertView *alert &＃61; [[UIAlertView alloc]initWithTitle:&＃64;"提示" message:&＃64;"确认退出程序&＃xff1f;" delegate:nil cancelButtonTitle:&＃64;"ok" otherButtonTitles:nil];[alert show];}}//创建一个navitem对象&＃xff0c;当然这个对象也有很多属性
-(UINavigationItem *) makeNavItem{UINavigationItem *navItem &＃61; [[UINavigationItem alloc]initWithTitle:&＃64;""];[navItem setTitle:[NSString stringWithFormat:&＃64;"第%ld个导航页",count]];UIBarButtonItem *leftBtn &＃61; [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:&＃64;selector(pop)];UIBarButtonItem *rightBtn &＃61; [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:&＃64;selector(push)];[navItem setLeftBarButtonItem:leftBtn];[navItem setRightBarButtonItem:rightBtn];return navItem;}- (void)didReceiveMemoryWarning {[super didReceiveMemoryWarning];// Dispose of any resources that can be recreated.
}&＃64;end