iOS App with multiple view controllers - ios

Question

My current application on appDelegate loads a main.xib screen which only contains an two images background and logo. This screen behind code determines if the user is logged on the system if not it will show the login else it will show the dashboard.
The application has been created as a single view application, sample code of the appDelegate:
// Override point for customization after application launch.
if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)
{
self.Main = [[vcMain alloc] initWithNibName:#"vcMain" bundle:nil];
self.window.rootViewController = self.Main;
[self.window makeKeyAndVisible];
}
else
{
self.MainiPad = [[vcMain_iPad alloc] initWithNibName:#"vcMain_iPad" bundle:nil];
self.window.rootViewController = self.MainiPad;
[self.window makeKeyAndVisible];
}
On the Main.m I have the following on the viewDidLoad:
if (islogged)
{
vcDashboard *vcDash = [[vcDashboard alloc] initWithNibName:#"vcDashboard" bundle:nil];
_ncMain = [[UINavigationController alloc] initWithRootViewController:vcDash];
_ncMain.navigationBar.barStyle = UIBarStyleBlackOpaque;
_ncMain.view.frame = self.view.bounds;
[self.view addSubview:_ncMain.view];
ViewActive = vDash;
}
else
{
vcLogin *login = [[vcLogin alloc] initWithNibName:#"vcLogin" bundle:nil];
login.modalPresentationStyle = UIModalPresentationFormSheet;
login.view.frame = self.view.bounds;
[self presentViewController:login animated:YES completion:nil];
}
There is a menu button available on the Dashboard that presents the user with a series of options to select another screen and when pressed it will activate the following method:
- (void)displayView:(NSString *)strView Notification:(NSNotification *)notification{
if(_ncMain)
{
[_ncMain.view removeFromSuperview];
_ncMain = nil;
}
if ([strView isEqual: #"Dashboard"])
{
vcDashboard *vcDash = [[vcDashboard alloc] initWithNibName:#"vcDashboard" bundle:nil];
_ncMain = [[UINavigationController alloc] initWithRootViewController:vcDash];
_ncMain.navigationBar.barStyle = UIBarStyleBlackOpaque;
_ncMain.view.frame = self.view.bounds;
[self.view addSubview:_ncMain.view];
ViewActive = vDash;
}
else if ([strView isEqual: #"Catalog"])
{
vcCatalog *vcCat = [[vcCatalog alloc] initWithNibName:#"vcCatalog" bundle:nil];
_ncMain = [[UINavigationController alloc] initWithRootViewController:vcCat];
_ncMain.navigationBar.barStyle = UIBarStyleBlackOpaque;
_ncMain.view.frame = self.view.bounds;
[self.view addSubview:_ncMain.view];
ViewActive = vCatalog;
}
else if ([strView isEqual: #"News"])
{
vcNews *vcNew = [[vcNews alloc] initWithNibName:#"vcNews" bundle:nil];
_ncMain = [[UINavigationController alloc] initWithRootViewController:vcNew];
_ncMain.navigationBar.barStyle = UIBarStyleBlackOpaque;
_ncMain.view.frame = self.view.bounds;
[self.view addSubview:_ncMain.view];
ViewActive = vNews;
}
}
My doubt here is I don't seem to know if this is the correct way of changing between screens when an option is selected from this menu and if is right to always addSubview to the principal screen. Don't know if using the navigationcontroller template is a solution. I'm concern of the memory consumed by the app when doing all of this, also I'm currently using ARC on the project.

Answer 1

I recommend you that avoid the addSubview method if possible. UiNAvigationController offer you a good way to handle different viewControllers. If you make addSubview the changeRotation event, for example, is not called. And when you make a pop the viewController is dealloced.
Good luck!