I have a simple application with two subclasses of UIViewController.
I want to change the view being displayed by my application's UIWindow by calling a method from one of my UIViewController subclasses.
Essentially I'm just messing around and I'm trying to construct a simple test application with a login screen, that after a user enters credentials a main view is presented. I'm not too familiar with the window and view mechanisms of iOS programming, and I'm currently reading http://developer.apple.com/library/ios/#documentation/WindowsViews/Conceptual/ViewPG_iPhoneOS/WindowsandViews/WindowsandViews.html#//apple_ref/doc/uid/TP40009503-CH2-SW1 and attempting to learn a bit about it.
If this is for the purpose of a login screen, you should add the main view controller to window directly, and add the login view controller as a modal view inside the main view controller.
Inside applicationDidFinishLaunching...
MainViewController *mainViewController = [[MainView....... // instantiate UINavigationController *navController = [[UINavigationController alloc]initWithRootViewController:mainViewController];
[mainViewController release];
[window addSubview:navController.view];
Inside MainViewController
-(void)viewWillAppear:(BOOL)animated
{
LoginViewController *loginVC = .... //instantiate
[self.navigationController presentModalViewController:loginVC animated:NO];
[loginVC release];
}
if login successful,
[self dismissModalViewControllerAnimated:YES];
Related
I have this code:
-(void)applicationDidBecomeActive:(UIApplication *)application {
JUnlockController *passcodeView = [[JUnlockController alloc] init];
[self.navigationController presentModalViewController:passcodeView animated:YES];
}
The problem is, when i have a modal view controller open in my app, it doesn't appear on top of it. I want to be able to find out which is the current viewcontroller that the user is looking at, so I can display it on top of there.
Instead of:
[self.navigationController presentModalViewController:passcodeView animated:YES];
use:
[self presentModalViewController:passcodeView animated:YES];
If your app is only navigated by that nav controller, you can ask it which viewController is visible:
[self.navigationController.visibleViewController presentModalViewController:passcodeView animated:YES];
Or else you can leverage the UIApplicationDidBecomeActiveNotification by having all ov your view controllers extend a custom class which registers for this on viewWillAppear and unregisters in viewWillDissapear; and in your custom base class you implement the callback which displays your modal.
edit note that this assumes you have a self.navigationController in your app delegate (which you setup). You may need to use something like self.window.rootViewController instead.
Before:
My App is based on indepent view controllers. I can switch from one to another by replacing the root view controller on the application delegate:
ade.window.rootViewController = newController;
... and all worked right, till now.
Tomorrow:
we have to add a NavigationController-based part of our App, which will help the users navigate through our:
Brands => Model Names => Colors
So, the user will choose a color, then click a button: now I will switch to another UIViewController (call it "pippo"), which actually resides outside that navigation hierarchy (I can't push it in the nav-controller for several methods, I'm forced doing so!).
What I want is to get back to my "Color" screen, from "pippo". So, I'm looking for a way to programmatically "navigate" the navigation controller I restore, I mean:
I restore my navigation controller
now I'm on Brands, but I don't want my users to be here, I want to show them the last color they was on (I saved it in the preferences)
how can I simulate the selection of a known brand and model?
Thanks a lot.
In applicationDidFinishLoading in App delegate:
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:rootViewController];
[window makeKeyAndVisible];
[window addSubview:navController.view];
That will instantiate the navigation controller and add it to the window as a view.
Now, in your rootViewController class (lets say its called FirstViewController) you can do this:
- (void)clickedAButton:(id)selector {
SecondViewController *nextViewController = [[SecondViewController alloc] initWithNibName:nil bundle:nil];
// and push it onto the 'navigation stack'
[self.navigationController pushNavigationController:nextViewController animated:YES];
// and release
[nextViewController release];
}
And in your SecondViewController you can navigate back through the stack using:
- (void)clickedAnotherButton:(id)selector {
// goes back to the last view controller in the stack
[self.navigationController popViewControllerAnimated:YES];
}
So for you it would go:
Set up navigation controller in the app delegate with Brand as the root view controller
User chooses their brand and you pushViewController:animated: the Model view controller. Then the user chooses their model and you pushViewController:animated: the Color view controller. Similarly the user chooses a color and you push the Pippo view controller. Now, if the user presses back (or you call popViewControllerAnimated:) it will go back to the Color view controller in the same state as when the user left it to go to the Pippo controller.
Write the following code in AppDelegate.m Class
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
MainViewController *mainViewController = [[MainViewController alloc] initWithNibName:#"MainViewController" bundle:nil];
self.nav = [[UINavigationController alloc] initWithRootViewController:mainViewController];
self.nav.navigationBarHidden = YES;
[mainViewController release];
[_window addSubview:nav.view];
[_window makeKeyAndVisible];
}
I'm making an iphone app out of the utility template in xcode. So in my FlispSideView I have a button that should show a custom image picker. I decided to use this nice one here link.
Now I made some changes cuz I'm not using a navigation controller to load the custom image picker (but rather modally) which is created programmatically inside the .m file. So I made the FlipSideView the delegate for the custom image picker but still lost when I come to loading the view. I created a xib file and tried to connect it to the image picker but that didn't work.
So I wonder what's the best way to do that?
I'm not sure I interpreted your question correctly, but based on the title, I think this might be what you are looking for:
// Initialize your custom controller and set the delegate
UIViewController *controller = [[UIViewController alloc] initWithNibName:#"MyView" bundle:nil];
controller.delegate = self;
// Set the title of your custom controller (optional)
controller.title = NSLocalizedString(#"My View", nil);
// Create a navigation controller with your custom controller as the root view controller
UINavigationController *navCon = [[UINavigationController alloc] initWithRootViewController:controller];
// Present the navigation controller as a modal view controller
[self.navigationController presentModalViewController:navCon animated:YES];
// Release objects you own
[navCon release];
[controller release];
If your image picker is a controller, and all the outlets on your xib are properly connected to it, this should work. You should be able to make your FlipSideView the delegate. Pressing cancel or done in the modal view should call a message in the delegate that says
[self.navigationController dismissModalViewControllerAnimated:YES];
EDIT:
Here is the first line of my example code updated to match the tutorial you are using:
CustomImagePicker *controller = [[CustomImagePicker alloc] init];
The rest is the same. You initialize a navigation controller with controller as the root view controller, then present the navigation controller as a modal view controller.
Creating navigation programatically
Use the code below to navigate programatically. Write the following code in
AppDelegate.m class
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
FirstViewController *firstViewController = [[FirstViewController alloc] initWithNibName:#"FirstViewController" bundle:nil];
self.nav = [[UINavigationController alloc] initWithRootViewController:firstViewController];
[_window addSubview:nav.view];
[_window makeKeyAndVisible];
}
I have created a view based application and in the appdelegate .h file I have created UINavigationcontroller object and added it to window subview. Next in the app did finish launching I had allocated and initialised a class that I want to be viewed when the app first launches with the navigation bar on the top of it.
So this is the code I have did to add the class to navigation bar
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// Override point for customization after application launch.
// Add the view controller's view to the window and display.
[window addSubview:navController.view];
//test is the class that i want to be viewed first when the app launches first
test *t = [[test alloc]initWithNibName:#"test" bundle:nil];
[navController.view addSubview:t.view];
[window makeKeyAndVisible];
return YES;
}
but the problem is my test class launches but it does not display the navigation bar. What may be the problem?
Use some like this (add these lines)
appDelegate.h
UINavigationController *navController
#property (nonatomic,retain) UINavigationController *navController;
and in .m
test *t = [[test alloc]initWithNibName:#"test" bundle:nil];
self.navController=[[[UINavigationController alloc] initWithRootViewController:t] autorelease];
[window addSubview:self.navController.view];
[window makeKeyAndVisible];
it helps you.
From other view you need to make object of the appDelegate class then access the navigation controller of that class
see this
yourAppDelegateClass *objAppDelegate=(yourAppDelegateClass *)[[UIApplication sharedApplication] delegate];
now for pushing a view
SecondView *s=[[[SecondView alloc] initWithNibName:#"yournibName" bundle:nil] autorelease];
[objAppDelegate.navController pushViewController:s animated:YES];
this concept help you.
You shouldn't add your own view controller's view as a subview of the navigation controller. This way, you hide the navigation controller's view (including the navigation bar) and it makes the navigation controller pointless, because it doesn't know that your view controller wants to be part of its navigation stack.
Instead, push it on the navigation controller's stack by using:
[navController pushViewController:myViewController animated:NO];
Navigation bar is not coming because you are setting navigation controller's view to your test view. You can do it by setting navigation controller's view controllers which requires an array as -
test *t = [[test alloc]initWithNibName:#"test" bundle:nil];
NSArray *viewControllers = [[NSArray alloc] initWithObjects:t,nil];
[self.navigationController setViewControllers:viewControllers];
First, I don't see where you alloc init your navController. Secondly, you don't add a viewController to a navigation controllers view, rather you push the view controller onto the stack, like this:
[navController pushViewController:t animated:NO];
Hope this helps.
I am creating a Navigation based iPhone application.
In that I have called a UiViewController using presentModalViewController. After that, the ViewController becomes visible. From that ViewController I need to call another ViewController using the sample presentModalViewController. Is this possible or not?
What do you mean by "call another uiviewcontroller"? (It really helps if you can be more detailed in your question.) If you mean, "slide in another view controller", then:
MyNewViewController *myNewViewController = [[MyNewViewController alloc] initWithNibName:#"MyNewViewController" bundle:nil];
[navigationController pushViewController:myNewViewController animated:YES];
[myNewViewController release];
...where:
MyNewViewController is the new view controller class that you want to slide in (the above code assumes you have an XIB file for the view controller class).
navigationController points to the current navigation controller. You'll have to replace it with something like [self navigationController], depending where you are in the view hierarchy.
U might be using following line to present a view controller.
//assume name of viewController which u want to present is "myViewController"
[self.navigationController presentModalViewController:myViewController animated:YES]
If you want to push an other ViewController or present an other ViewController then u will need to replace above line with following lines.
//[self.navigationController presentModalViewController:myViewController animated:YES];
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:myViewController];
navigationController.navigationBarHidden = YES; //if u want to show navigation bar then remove this line
[self presentModalViewController:navigationController animated:YES];
After using above code you can present or push other view controllers within presented view controller.
Hope it will solve your problem :)