I have created a new iPhone "View-based Application" in Xcode. I then added a new "UIViewController subclass" and checked the "with XIB for user interface. Now the issue I have is that after hooking up all the variables and message handlers, I cannot push the new controller onto the stack using the following code:
[self.navigationController pushViewController:self.cabinetController
animated:YES];
All the variables and views are hooked up correctly, so all that I can think of is that its the way I am doing it, by pushing it onto the "navigationController". Is there something I am missing here? (I am very new to iPhone and Apple programming in general, so its probably a very simple oversight).
I realise that not enough information has been supplied ... here is a link to the project. Please note that it is an educational exercise has some creatively names classes.
http://files.me.com/nippysaurus/4yqz8t
In your appDelegate create a UINavigationController instance variable and then use your existing viewController as the rootViewController of the navigation controller.
e.g. in pure code using a UITableViewController (you can use xibs as well which your template app probably does).
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Create root view and navigation controller
UITableViewController *rootViewController = [[[UITableViewController alloc] initWithStyle:UITableViewStyleGrouped] autorelease];
self.navigationController = [[[UINavigationController alloc] initWithRootViewController:rootViewController] autorelease];
// Not necessary if you're using xibs
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
// Add the nav controller's root view to the window
[window addSubview:navigationController.view];
[window makeKeyAndVisible];
return YES;
}
You need to change your view controller to a navigation controller, with its root view controller set as the current view controller.
If you examine your self.navigationController, you will realize it is nil. Messaging nil doesn't hurt, so no error message here.
Add another layer with a UINavigationController, and add your RandomShitViewController (nice name btw.) as its root view controller.
The navigation controller handles the push / pop part, your old controller manages its view.
Related
I have received a project from a client that I need to compile, but when I run it gives error Application windows are expected to have a root view controller at the end of application launch and EXC_BAD_Access (code=2, address=0x0)
as far as I know this is due to application:didFinishLaunchWithOptions: in the AppDelegate, but the problem with my project is that there is no AppDelegate file.
EDIT:
I tried to run the project on Xcode 4.5.1 now it is giving the error address doesn't contain a section that points to a section in a object file.
The problem is that there is no AppDelegate file. That is usually where the root view controller is set
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];
// Override point for customization after application launch.
self.viewController = [[[ViewController alloc] initWithNibName:#"ViewController" bundle:nil] autorelease];
// set root view controller
self.window.rootViewController = self.viewController;
[self.window makeKeyAndVisible];
return YES;
}
I also experienced the "Application windows are expected to have a root view controller" error message.
If you are using a storyboard and you have verified:
The app delegate application:didFinishLaunchingWithOptions method is
returning TRUE and doing nothing else.
The view controller is set in IB to be the initial view controller.
The storyboard is appropriately set on the TARGETS Summary tab.
Verify that you have not created a "view" UIView #property and #synthezised it in the view controller implementation. I experienced this and through a lengthy process of elimination had my DOH moment when I realized I had created a "view" UIView property named exactly like the one IB had created and linked to the view controller.
Hope this helps.
Hello, I have this code in my AppDelegate:
[window addSubview:viewController.view];
[window makeKeyAndVisible];
return YES;
Now I want to create a XIB file in which I want to put a UINavigationController and add a UITableView. How do I create this through code without changing the delegate class?
I've tried this but it does not work:
PlacesTableViewController *obj = [[PlacesTableViewController alloc]init];
obj.title = #"Farmacie intorno a te";
UINavigationController *navC = [[UINavigationController alloc]initWithRootViewController:obj];
[self.window addSubview:navC.view];
First, the "modern" way to set up your window is to use the window's rootViewController property:
window.rootViewController = someViewController;
The old way, where you add a view controller's view to the window as a subview, still works but the app will log a complaint about wanting the root view controller to be set up by the time the app is done launching.
Second, if you're going to replace the root view controller (in this case you're replacing your viewController with navC) using the old style, you'd want to remove the old view controller's view from the window. Your best bet is to just use the window's rootViewController property, since your code will be expected to use that going forward anyway.
I'm new to iPhone development. I tried to build a simple application with a window and a navigation controller as a sub-view of this window. The problem is this: the sub view did not load when I launch the application. I just have a windows with black screen. To load the view controller, I have to quit the application and launch it a second time, then I have my sub view with the navigation controller. I added a button directly in the window to make sure that the black screen is not a problem, but I saw the button at startup.
This is the code I have in my AppDelegate:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]]autorelease];
[self.window addSubview:_navigationController.view];
[self.window makeKeyAndVisible];
return YES;
}
Do you have any solution for this problem?
Thank you.
You need to make sure that you have your view hierarchy setup. The window's rootViewController will be the UINavigationController. The UINavigationController controls a hierarchy of viewControllers, so when you instantiate it, you need to assign a rootViewController. Often times this is a subclass of a UITableView.
Because you are alloc/initing the window, I'm assuming that you do not have a XIB/NIB with the UINavigationController and an associated rootViewController like a UITableViewController. Also, rather than adding the view of your navigation controller, you need to assign the rootViewController, to the window. Since iOS4 this is the preferred way of doing things. See here as well. Try this code:
YourViewController *yourViewController = /* code for alloc/initing your viewController */
_navigationController=[[UINavigationController alloc] initWithRootViewController:yourViewController ]
self.window.rootViewController=_navigationController; /* instead of using [self.window addSubview: _navigationController.view] */
[self.window makeKeyAndVisible];
If you are using a XIB/NIB, then you need to make sure the _navigationController is wired up to the XIB file and has a subclass of a viewController wired up as it's rootViewController.
Good Luck
I have an app that has a UITabBarController, one of the tabs of which is configured for a navigation controller.
Based on certain logic I need to attach a different root view to the navigation controller inside the tab at application launch time.
This is easily done in interface builder however, because I need to figure out what view to attach at launch time interface builder is not much use to me in this situation.
I'm guessing I will need to perform this in the applicationDidFinishLaunching method in my app delegate class by somehow getting the tab I'm interested in, and pushing the view onto it's navigation controller?
How would I go about this?
Thanks.
You're on the right track. In your app delegate's applicationDidFinishLaunching method, you need to look at whatever your condition is and pick the right thing to set as the UINavigationController's root view controller.
I'm guessing this is a login screen or something? And if you have a cached login from an earlier session you don't show it again? Is that it?
If you take a look at that method in your application delegate, you'll see where the default root view controller is getting instantiated and pushed into the nav controller. Just duplicate that code inside an if() statement. I've done this, it's straightforward.
So what I did in my applicationDidFinishLaunching method was:
// get the array of tabs
NSArray *tabBarArray = tabBarController.viewControllers;
// in my case the navigation controller I'm interested in is in the 4th tab
UINavigationController *navigationController = [tabBarArray objectAtIndex:4];
if(someLogic == true) {
ViewController1 *viewController1 = [[viewController1 alloc] initWithNibName:#"View1" bundle:nil];
[navigationController pushViewController:viewController1 animated:NO];
[viewController1 release];
}
else {
ViewController2 *viewController2 = [[viewController2 alloc] initWithNibName:#"View2" bundle:nil];
[navigationController pushViewController:viewController2 animated:NO];
[viewController2 release];
}
Everything working well.
I built an application. On the one my views I used TableView. So now I want to change this Table view to a navigation controller.
1- How can I change UITable view to Navigation Controller.؟
The easiest way to achieve this is to create a new 'Navigation-based Application'. This will set up everything you need. By default this will set you up with simple RootViewController, if you want you can change this to be your TableViewController by editing the application delegate
- (void)applicationDidFinishLaunching:(UIApplication *)application {
// Override point for customization after app launch
RootViewController *rootViewController = (RootViewController *)[navigationController topViewController];
rootViewController.managedObjectContext = self.managedObjectContext;
[window addSubview:[navigationController view]];
[window makeKeyAndVisible];
}
All you need to do is copy your TableViewController into the new project and change the RootViewController to be yours
If you have started with one of the template project in XCode find the .xib file for your view and launch InterfaceBuilder by double clicking the .xib file. You can manipulate the view directly by dragging and dropping components as well as adding components from a palette.
I would walk through one of Apples tutorials and get a feel for working with InterfaceBuilder - this tutorial shows adding a view controller.
Thank you everybody . finally i figured out :D , just put this code :
UINavigationController *myNav=[[UINavigationController alloc] initWithRootViewController:[[YourViewController alloc] initWithNibName:#"YourViewController" bundle:nil]];
[self presentModalViewController:myNav animated:YES];