pushViewController没有从AppDelegate工作

Question

我想通过警告视图从AppDelegate推送到视图控制器。但这行不通。只有警报视图被解除。问题在哪里?提前感谢你的帮助。(N.B>我的初始视图在故事板中，但我正在推入视图控制器nib)

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
loginReapeat = [NSTimer scheduledTimerWithTimeInterval:60.0 target:self selector:@selector(repeatLoginProcess) userInfo:nil repeats:YES];
//First Launch Settings
if ([[NSUserDefaults standardUserDefaults] boolForKey:@"FirstLaunch"])
{
}
else
{
    [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"FirstLaunch"];
    [[NSUserDefaults standardUserDefaults] synchronize];
    [self alertShow];
}
[window addSubview:[navigationController view]];
[window makeKeyAndVisible];
return YES;
} 
-(void)alertShow{
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"Help!" message:@"Need some help to use this App? Please tap the 'Help' button." delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Help",nil];
[alert show];
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
NSString *title = [alertView buttonTitleAtIndex:buttonIndex];
if([title isEqualToString:@"Help"])
{
    SignUp *signUp = [[SignUp alloc]initWithNibName:@"SignUp" bundle:nil];
    [self.navigationController pushViewController:signUp animated:YES];
}
} 

Answer 1

试试这个:

SignUp *signUp = [[SignUp alloc]initWithNibName:@"SignUp" bundle:nil];                
self.navigationController = [[UINavigationController alloc] initWithRootViewController:signUp];
self.window.rootViewController = self.navigationController;

Answer 2

你不能从App Delegate中推送，相反，你可以根据用户从UIAlertView中选择哪个UIViewController显示为rootviewcontroller。

self.window.rootViewController = self.navController;

Answer 3

    SignUp *signUp = [[SignUp alloc]initWithNibName:@"SignUp" bundle:nil];                
   UINavigationController *masterNavigationController = [[[UINavigationController alloc] initWithRootViewController:signUp ] autorelease];
    self.window.rootViewController = masterNavigationController;

Answer 4

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
ViewControllerName *home=[[ViewControllerName alloc] initWithNibName:@"ViewControllerName" bundle:nil];
 self.window.rootViewController=home;
navcontroller=[[UINavigationController alloc]initWithRootViewController:home];
self.window.rootViewController = self.navController.view;
[self.window makeKeyAndVisible];
return YES;
}