Question

How could i create a modal view , maybe from the delegate to check if its the first time the application launches and show a modal view with a dismiss button , in order to inform the user about something important?

I need the view to show ONLY the first time the application is launched and never again.

Answer 1

You can achive this using NSUserDefaults.

In delegate.h file

NSString * firstTime;

In .m file

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
     self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
        // Override point for customization after application launch.
    self.viewController = [[ViewController alloc] initWithNibName:@"ViewController" bundle:nil];
    self.window.rootViewController = self.viewController;
    [self.window makeKeyAndVisible];

    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    NSString *myStr = [defaults objectForKey:@"str"];
    firstTime =myStr;

    if (firstTime.length==0) {
        UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"hi" message:@"You have open this app first time" delegate:self cancelButtonTitle:@"ok" otherButtonTitles: nil];
        [alert show];
        [self firstTime];
    }

    return YES;
}

-(void)firstTime
{
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    NSString *myStr = @"first";
    [defaults setObject:myStr forKey:@"str"];
    [defaults synchronize];
}