ios - appDelegate 的 alertView 不会切换 View uppon buttonIndex

Question

我正在尝试从 appDelegate 创建一个 alertView，但我无法让它工作。当应用程序首次启动时，alertView 将充当免责声明。我无法让它工作..introViewcontroller 没有出现。我究竟做错了什么？附言。我使用 Storyboard，除了 intoViewController 是一个 nib 文件。我的 Root View Controller 是一个“fisrtViewController”这是我的代码:谢谢..

int a;

并在 didFinishLaunchingWithOptions 中

    if ( a == 0) {

UIAlertView *disclaimer = [[UIAlertView alloc] initWithTitle:@"Read Before use" message:@"By using this app you agree to its terms and conditions.\n\n\n\n\n\n\n\n\n\n\ntext heren\n\n\n\n\n\n\n\n\n\n\n\n\n" delegate:self cancelButtonTitle:@"No!" otherButtonTitles:@"Yes Let me In", nil];

[disclaimer show];
}


// Override point for customization after application launch.
return YES;
}

-(void) alertView:(UIAlertView *) alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
if (buttonIndex == 1) {
  //  FirstViewController *firstView = [[FirstViewController alloc] init];
    a+=1;
  //  [self.viewController presentModalViewController:firstView animated:YES];
}
else if (buttonIndex == 2) {
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Sorry!" message:@"You are not allowed to use this app due to the fact that you did not agree to the terms and Conditions. Please exit this app!" delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil, nil];
    [alert show];

if (buttonIndex ==1) {
       introViewController *intro = [[introViewController alloc] initWithNibName:@"introViewController" bundle:nil];
       [self.viewController presentModalViewController:intro animated:YES];
   introViewController *intro = [[introViewController alloc] initWithNibName:@"introViewController" bundle:nil];
   [self.viewController presentModalViewController:intro animated:YES];
}
}

Answer 1

啊...现在我明白你想做什么了。

你的问题是self.viewController在您尝试呈现新的模态 ViewController 之前未设置。另外，我认为你的 buttonIndex 是一个。

改为尝试:

if (buttonIndex == 1)
    {
        _window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
        introViewController *intro = [[introViewController alloc] initWithNibName:@"introViewController" bundle:nil];
        _window.rootViewController = _intro;
        [_window makeKeyAndVisible];
    }

因为你的问题与UIAlertView无关，您可能想更改问题的标题和描述，以使其更清楚，以便其他人遇到类似问题。

编码愉快! :)