How to move to another view without using a button - iphone

Question

My first view displays an image and action indicator while web-servers and database function are run in that background. I want the application to go to my tab view when the functions have been completed. How do I do this?
Here is what the views look like.
What I have tried:
TabBarViewController *tab = [[TabBarViewController alloc]init];
[self presentViewController:tab animated:NO completion:nil];
and
[self performSegueWithIdentifier:#"first" sender:self];
Please can you help my to understand how to do this. I have spent many hours googling this problem and couldn't work out how to do it.
Thanks
EDIT: Added Code

Answer 1

Since you are downloading data you can get a call when the downloading request gets finished
like the method below
- (void)requestFinished:(ASIHTTPRequest *)request
and in this method you can very well present your TabBarViewController.

Answer 2

You can use GCD to make this happen.
For instance in your firstViewController where you trigger downloading you can do:
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_LOW, 0), ^{
[model downloadData];
dispatch_sync(dispatch_get_main_queue(), ^{
[self performSegueWithIdentifier:#"YourSegueIdentifier" sender:self];
});
});
I assume your downloadData method is synchronous, if not you can use notifications in your model. Once data is retrieved you could postNamedNotification from NSNotificationCenter and in firstViewController you could register for notification and after receiving it you would call performSegueWithIdentifier

Answer 3

You Can Declare A separate Method for that.
Call the below method when your function completes.
[self performSelector:#selector(gotonext:) withObject:nil afterDelay:4.0];
-(void)gotonext;
{
TabBarViewController *tab = [[TabBarViewController alloc]init];
[self presentViewController:tab animated:NO completion:nil];
}

Answer 4

Take one splashView Image at starting, like bellow...
#interface AppDelegate : UIResponder <UIApplicationDelegate>{
UIImageView *splashView;
}
#property (nonatomic, retain) UIImageView *splashView;
#end
in AppDelegate.m file...
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)
{
splashView = [[UIImageView alloc] initWithFrame:iphoneFrame];
splashView.image = [UIImage imageNamed:#"Default"];
[self.window addSubview:splashView];
[self.window makeKeyAndVisible];
UIViewController *viewController1 = [[[RootViewController alloc] initWithNibName:#"RootViewController" bundle:nil] autorelease];
UINavigationController *navviewController1=[[UINavigationController alloc]initWithRootViewController:viewController1];
navviewController1.title = #"FirstTitle";
// navviewController1.navigationBarHidden=YES;
UIViewController *viewController2 = [[[yourviewController2 alloc] initWithNibName:#"yourviewController2" bundle:nil] autorelease];
UINavigationController *navviewController2=[[UINavigationController alloc]initWithRootViewController:viewController2];
// navviewController2.navigationBarHidden=YES;
navviewController2.title = #"SecondTitle";
UIViewController *viewController3 = [[[yourviewController3 alloc] initWithNibName:#"yourviewController2" bundle:nil] autorelease];
UINavigationController *navviewController3=[[UINavigationController alloc]initWithRootViewController:viewController3];
// navviewController3.navigationBarHidden=YES;
navviewController3.title = #"ThirdTitle";
//..... and so on depend on your requirement
self.tabBarController = [[[UITabBarController alloc] init] autorelease];
self.tabBarController.viewControllers = [NSArray arrayWithObjects:navviewController1, navviewController2 , navviewController3 ,nil];
[self performSelector:#selector(loadViewIphone) withObject:nil afterDelay:2.0];//**add this line at your all data are loading completed**
}
else
{
splashView = [[UIImageView alloc] initWithFrame:ipadFrame];
splashView.image = [UIImage imageNamed:#"Default_iPad"];
[self.window addSubview:splashView];
[self.window makeKeyAndVisible];
[self performSelector:#selector(loadViewIpad) withObject:nil afterDelay:2.0];
}
[self.window makeKeyAndVisible];
return YES;
}
-(void)loadViewIphone
{
[splashView removeFromSuperview];
[self.window addSubview:tabBarController.view];
[self.window makeKeyAndVisible];
CATransition *animation = [CATransition animation];
[animation setDelegate:self];
[animation setType:kCATransitionFromBottom];
[animation setDuration:1.0];
[animation setTimingFunction:[CAMediaTimingFunction functionWithName:
kCAMediaTimingFunctionEaseInEaseOut]];
[[self.window layer] addAnimation:animation forKey:#"transitionViewAnimation"];
[self.window makeKeyAndVisible];
}
i hope this help you...

Answer 5

Hm... What if you put
TabBarViewController *tab = [[TabBarViewController alloc]init];
[self presentViewController:tab animated:NO completion:nil];
In
dispatch_async(dispatch_get_main_queue(), ^{
//stop the loader once the database stuff has finished and get rid of the text
[[self firstLoader]stopAnimating];
self.downloadingLabel.text = #"";
});
UPDATE: If you want to do this sync
dispatch_sync(a_queue, ^{ wait_for_me(); });
And after that present your VC.