NavigationController Skip View - iphone

Is it possible to skip a view in a Navigation Controller? My structure is as follows:
**Main Screen Navigation Controller**
-Main Screen View
**Options Navigation Controller (Modal transition from Main Screen View)**
-Options Screen View
--Sub Options Screen View(Push from Options View)
On the first load of the application, I want to present a "Welcome" UIAlertView that will present the "Sub Options" screen.
Thanks

You'll have to build your navigation stack programmatically and then modally display the UINavigationController. Use the viewControllers property. The last view controller in the passed in array will become the top view controller.
OptionsViewController *ovc = [[OptionsViewController alloc] init];
SubOptionsViewController *sovc = [[SubOptionsViewController alloc] init];
UINavigationController *nav = [[UINavigationController alloc] init];
nav.viewControllers = [NSArray arrayWithObjects:ovc, sovc, nil];
[self presentModalViewController:nav animated:YES];

Yes. If you read the documentation for UINavigationController, you'll see there's a method called setViewControllers:animated: that you can use to explicitly set the entire stack of view controllers at once.

Related

view is hiding tabbarcontroller

I have developed a tab based iphone application.
In this, I am facing a problem as described below:
The view associated with 1st tab bar contains 2-3 buttons. Action of these buttons are to load another view. Now on pressing these buttons the views are loading but in full size(320x480) and hiding the tab bar.
I want to load that view just above the tab bar so that tab bar is accessible.
I explicitly set the view frame in that view's viewDidLoad function, but it is not working.
Please help me out.
Try this :
You need to start with view based application. And then create a UITabbarController in you appDelegate file.
Appdelegate.h
UITabBarController *tabBarController;
// set properties
Appdelegate.m
// Synthsize
tabBarController = [[UITabBarController alloc] init];
tabBarController.delegate=self;
//Adding Search,Nearby,Map,AboutUs,Favorites Tabs to tabBarController
Search * search = [[Search alloc] init];
UINavigationController *searchNav = [[UINavigationController alloc] initWithRootViewController:search];
Nearby* nearby = [[Nearby alloc] init];
UINavigationController *nearbyNav = [[UINavigationController alloc] initWithRootViewController:nearby];
Map* map = [[Map alloc] init];
UINavigationController *mapNav = [[UINavigationController alloc] initWithRootViewController:map];
AboutUs* aboutUs = [[AboutUs alloc] init];
UINavigationController *aboutUsNav = [[UINavigationController alloc] initWithRootViewController:aboutUs];
Favorites* favorites = [[Favorites alloc] init];
UINavigationController *favoritesNav = [[UINavigationController alloc] initWithRootViewController:favorites];
NSArray* controllers = [NSArray arrayWithObjects:searchNav,nearbyNav,mapNav,aboutUsNav,favoritesNav, nil];
tabBarController.viewControllers = controllers;
[window addSubview:tabBarController.view];
You can accordingly manage in which tab you want to place navigation controller or only a view controller.
Then in each of the view controllers mentioned above you need to implement
- (id)init {}
in which you can set Tab name and image.
Rename the tbs as per your requirement. Place 2 buttons in the one of the views which is Navigation controller.
Hope this helps.
Typical application navigation allows the user to freely move forwards and backwards, between tabs etc. This is facilitated by pushing and popping ViewController's on the navigation bar stack.
In certain scenarios you want to force the user to complete some task and this is when you should use a modal view controller. When the application presents a modal view the idea is that the user should NOT be able to navigate away from the view, instead they should only be able to complete or cancel the action and hence the default behavior for a modal view is to hide the navigation bar, tab bar etc.
It sounds to me from your description that you are performing navigation and not a modal task and thus can I recommend using pushViewController instead of presentModalViewController?
If you are only using presentModalViewController because you want a bottom to top animation then you'll need to use a custom animation.

My viewcontroller (in the navcontroller) I load in my app delegate overlaps the tabbar

I'm having trouble initializing a viewcontroller when the app loads in my app delegate. The viewcontroller loads okay, but it overlaps the tabbar that I have at the bottom. Do I need to create another viewcontroller and have it load into that in the app delegate? I currently have a tabBarController set up in my MainWindow.xib, which contains Navigation controllers and inside those are viewControllers.
Here is my code...
In my didFinishLaunchingWithOptions I have:
sub = [[SubGabViewController alloc] initWithNibName:#"SubGabViewController" bundle:nil];
nav = [[UINavigationController alloc] initWithRootViewController:sub];
[window addSubview:nav.view];
Should it be something like?
sub = [[SubGabViewController alloc] initWithNibName:#"SubGabViewController" bundle:nil];
nav = [[UINavigationController alloc] initWithRootViewController:sub];
[newViewController.view addSubview:nav.view];
Thanks!
If you're trying to use a UITabBarController, each tab has its own root view controller (these can even be UINavigationController objects). Assuming you have a property for self.tabBarController (I think this gets created by default in Xcode if you are doing a tab-bar app), then:
sub = [[SubGabViewController alloc] initWithNibName:#"SubGabViewContrller" bundle:nil];
nav = [[UINavigationContoller alloc] initWithRootViewController:sub];
[self.tabBarController setViewControllers:[NSArray arrayWithObject:nav] animated:NO];
self.window.rootViewController = self.tabBarController;
// Clean up memory here... only if you don't need references to them
[sub release];
[nav release];
With setViewControllers:animated: you should probably include additional view controllers in the NSArray, otherwise you'll end up with a tab bar only containing one item!
[window addSubview:tabBarController.view]; would be right......
Rather than adding navigation controller using code..... you should add it from Interface Builder.... in interface builder remove the tabBarItem and add a navigationController on it and then set viewController for that navigation controller..........
create an outlet of tabBarController in appDelegate so that you can add it on window. Pleas do not forget to make connection between components in Interface Builder.
Thanks,

Maintain Title Bar in ModalViewController

When using the modalViewController, I found that that only way to keep a title bar and buttons on the screen that I jump to was to create a navigation controller and set the modalView screen as the rootView of the navigation controller (as below).
userNameViewController = [[UserNameViewController alloc] init];
UINavigationController *cntrol = [[UINavigationController alloc] initWithRootViewController:userNameViewController];
[self.navigationController presentModalViewController:cntrol animated:YES];
[userNameViewController release];
[cntrol release];
Why can't I simply this by using the original viewController as the modalView (as below)?
userNameViewController = [[UserNameViewController alloc] init];
[self presentModalViewController:userNameViewController animated:YES];
Because the navigation bar you usually see belongs to the navigation controller, not to its children view controllers.
You could create your own navigation bar and add it to your controller's view. However, it would require some relayout (and that's probably why it's easier to just recreate a navigation controller).

Iphone: Unable to return back from navigation bar controller

I have a very simple question. I have a view controller. In the view controller, i have added few buttons. On button click I have to start a tab bar controller (each of which has navigation controller).
Code Snippet:
- (IBAction) pushNewsAlertsController:(id)sender {
//Create a navigation controller
UINavigationController *FirstNavController = [[UINavigationController alloc] init] ;
//create the view controller (table view controller)
FirstViewController *firstViewController = [[FirstViewController alloc] init];
[FirstNavController pushViewController:firstViewController animated:YES];
//Create a navigation controller
UINavigationController *secondNavController = [[UINavigationController alloc] init] ;
//create the view controller (table view controller)
SecondViewController *secondViewController = [[SecondViewController alloc] init];
[secondNavController pushViewController:secondViewController animated:YES];
// Set the array of view controllers
tabBarController.viewControllers = [NSArray arrayWithObjects:firstNavController, secondNavController, nil] ;
//Add the tab bar controller's view to the window
[self.view addSubview:tabBarController.view];
}
I am able to add the tabviews and navigation controller. The problem is I am unable to get back to the main view once the button is clicked.
Can anyone guide me on how to get back to the previous view so that I can click other buttons.
In this case, I would consider presenting the tab bar controller modally. It's a cleaner way of organizing your views in the same way the user interface is organized. You can just dismiss the modal presentation to go back to the previous view. Read View Controller Programming Guide for iOS about similar advice and examples.
Not sure if I get what you are trying to do, but if you want the tab bar controller view to disappear again, the only way would be the inverse of
[self.view addSubview:tabBarController.view];
which could be
[tabBarController.view removeFromSuperview];
I must say it looks like an odd construction you're building, but it may work nevertheless.

How to hide a tabbar at the app startup?

So, I want my app starts with a UIViewController(without seeing a tabbar), and then enter a UITableView with navigationbar and tabbar. the problem is that the Tabbar is visible at the app starts up, anyone can help on this will be very appreciated...
I think you should either send -presentModalViewController:animated: to your main UIViewController with the tab bar controller as an argument or just do this:
[myWindow addSubview: myTabBarController.view];
Make your app a navigation based application (rather than a tab bar based one) then add a tab bar on the UITableView.
There is help for adding the UITabBar here
I do it like this : in this case drawing a table view and map view (From the Locati application)
tabBarController = [[UITabBarController alloc] init]; // creates your tab bar so you can add everything else to it
searchTableViewController = [[SearchTableViewController alloc] init]; // creates your table view - this should be a UIViewController with a table view in it, or UITableViewController
UINavigationController *searchTableNavController = [[[UINavigationController alloc] initWithRootViewController:searchTableViewController] autorelease];
[searchTableViewController release]; // creates your table view's navigation controller, then adds the view controller you made. Note I then let go of the view controller as the navigation controller now holds onto it
searchMapViewController = [[SearchMapViewController alloc] init];
UINavigationController *mapTableNavController = [[[UINavigationController alloc] initWithRootViewController:searchMapViewController] autorelease];
[searchMapViewController release]; // does exactly the same as the first round, but for your second tab at the bottom of the bar.
tabBarController.viewControllers = [NSArray arrayWithObjects:searchTableNavController, mapTableNavController, nil]; //add both of your navigation controllers to the tab bar. You can put as many controllers on as you like
I found this pattern a long time ago. Sorry that I can't point at the original.
YOu then need to add the tabbarcontoller to the relevant view ([...view addSubView:tabBarController];) possibly setting frame first.