NSUserDefaults问题

Question

我在我的app委托applicationDidFinishLaunching方法中有这个:

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
if([defaults objectForKey:@"AcceptTC"] == nil){
    NSDictionary *appDefaults = [NSDictionary dictionaryWithObject:@"NO" forKey:@"AcceptTC"];
    [defaults registerDefaults:appDefaults];
}

我在RootViewController viewDidLoad方法中有这个:

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
if(![defaults boolForKey:@"AcceptTC"]){
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Notice" message:@"By using this application you agree to be bound by the Terms and Conditions as stated within this application." delegate:self cancelButtonTitle:@"No Deal" otherButtonTitles:@"I Understand",nil];
    [alert show];
    [alert release];
}

和我的警报视图委托这样做:

if(buttonIndex == 0){
            exit(0);
        }
        else{
            NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
            [defaults setObject:@"YES" forKey:@"AcceptTC"];
        }

但是,当我单击"我理解"(按钮索引1)然后重新启动应用程序时,我仍然会看到警报视图!即使我确定将值设置为YES.

我不知道如何改变这一点.:(我只希望它显示用户第一次启动应用程序 - 我不想每次他们想要使用它时继续显示它.

谢谢

Answer 1

在我的应用程序中我使用NSUserDefaults与bool,工作正常.

当第一个ViewController加载时,它将执行:

BOOL terms = [[NSUserDefaults standardUserDefaults] boolForKey:@"termsaccepted"];

if (!terms) {
   [self presentModalViewController:disclaimerViewController animated:YES];
}

在免责声明视图中,点击按钮后:

[[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"termsaccepted"];
[[NSUserDefaults standardUserDefaults] synchronize];

我想你错过了"同步"部分.但是我发现使用bool也更精简了.