Button的种类

1、添加UIBarButtonItem:

1. - (void)viewDidLoad  
2. {  
3.     [super viewDidLoad];  
4.   
5.     UIBarButtonItem *leftButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:@selector(selectLeftAction:)];  
6.     self.navigationItem.leftBarButtonItem = leftButton;  
7.       
8.     UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd  target:self action:@selector(selectRightAction:)];  
9.     self.navigationItem.rightBarButtonItem = rightButton;<p class="p1">}</p> 

以上都是以后要用到得item。。。含义很明显，有了它们以后得item不再会乱用。。。

2、页面间切换：

主页面的设置：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

{

    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    self.window.backgroundColor = [UIColor whiteColor];

    LZWelcomeViewController *rootController = [[LZWelcomeViewController alloc] init];

    LZRootViewController *rootController1 = [[LZRootViewController alloc] init];

//之前错误之处：

//self.navController = [[UINavigationController alloc] initWithRootViewController:rootController];

//[self.navController setNavigationBarHidden:YES];

//[self.window addSubview:navController.view];

//welController = rootController;

//判断是不是第一次使用此应用，不是第一次则跳过WelcomeView

    if (![[NSUserDefaults standardUserDefaults] boolForKey:@"everLaunched"]) {

     [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"everLaunched"];

     [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"firstLaunch"];

     }

     else{

     [[NSUserDefaults standardUserDefaults] setBool:NO forKey:@"firstLaunch"];

     }

     if ([[NSUserDefaults standardUserDefaults] boolForKey:@"firstLaunch"]){

     self.window.rootViewController = rootController;

     }else{

     self.window.rootViewController = rootController1;

     }

    [self.window makeKeyAndVisible];

    return YES;

}