UINavigationController, simply hiding the navigation bar - objective-c

I've I have a simple noob question, I would like to hide the navigation bar of a UINavigationController, but I'm pretty sure I`m not calling the right object .
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
UIViewController *rootViewController = [[[TestViewController alloc] init] autorelease];
viewController = [ [UINavigationController alloc] initWithRootViewController:rootViewController];
[window addSubview:viewController.view];
[window addSubview: rootViewController.view];
[window makeKeyAndVisible];
return YES;
}
Now, I`ve tried, this :
-(void)hideBar {
viewController.navigationBarHidden = YES;
}
It is complaining that "navigationBarHidden" not found on object type UIViewController, obviously I would need to call the UINavigation controller instead, but that's where I'm stuck ...

Try:
[self.navigationController setNavigationBarHidden:YES];
within your TestViewController. A good place is in viewDidLoad
Also, while we're at it, remove the line [window addSubview:rootViewController.view];, you don't need it.

In Navigation controller's root view controller's method viewDidLoad write this -
[self.navigationController setNavigationBarHidden:TRUE];
in your case its TestViewController.

Related

iOS 7 - Setting the current view controller as root of navigation

I need to set the view controller of the home screen as the the root of the navigation controller, no matter how the user reaches it (push/show or custom segue)
The following code put in the viewDidLoad of a view controller seems to have no effect with iOS 7:
[self.navigationController setViewControllers:#[self]];
The navigation stack does not change at all.
Have you ever experienced any similar issue?
Thanks,
DAN
Call your UIViewController method from app delegate like this..try it out.
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
ViewController* pp = [[ViewController alloc] init];
UINavigationController* nav = [[UINavigationController alloc] initWithRootViewController:pp];
self.window.rootViewController = nav; or [self.window setrootviewcontroller=nav];
[self.window addSubview:[nav view]];
[self.window makeKeyAndVisible];
Only one line to make your current viewController as rootviewcontroller
[[[UIApplication sharedApplication] delegate] window].rootViewController = self;
Create global reference of navigation controller in App Delegate and then with the reference of appDelegate you can change you rootView controller anywhere just type below code :
[appDelegate.navigaitonController initWithRootViewController:viewController];
Note: Here viewController is new viewcontroller reference which you want to set as root of navigation controller .

self.navigationController == nil after awaking from LocalNotification

I'm working in Xcode 4.3.2
I implemented Local Notifications that alert the user of a new event at a predetermined time. So when my app is in the background and the clock strikes 8 am (for instance), the user will get a notification from my app.
When the user decides to view the app from the background I load a nib. Currently, this nib works properly: it shows the view as it was it arranged in the nib. However, after the nib is shown to the user, I want to forward the user to a different view in the LocalNotificationsHandler.m. When I attempt to push the second view, my app fails. So while there isn't an error message, it seems the second nib will not load.
In short the flow goes as follows:
user gets notification while my app is running in the background
user chooses to view the app
the LocalNotificationsHandler nib will load
self.navigationController == nil (in LocalNotificationsHandler.m)
self.navigationController will not "[pushViewController: "new view" animated:YES]" to get a new view
I'm wondering if there is something I'm missing from my AppDelegate.m file so I've included
"didFinishLaunchingWithOptions" from my AppDelegate.m file:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// Override point for customization after application launch.
// Add the navigation controller's view to the window and display.
NSLog(#"did finish launching with options");
[self.window addSubview:tabBarController.view];
[self.window makeKeyAndVisible];
[[UIApplication sharedApplication] registerForRemoteNotificationTypes:(UIRemoteNotificationTypeAlert | UIRemoteNotificationTypeBadge | UIRemoteNotificationTypeSound)];
if (self.locationManager == nil)
{
locationManager = [[CLLocationManager alloc] init];
locationManager.purpose = #"We will try to use you location";
}
if([CLLocationManager locationServicesEnabled])
{
[self.locationManager startUpdatingLocation];
}
self.navigationController.navigationBar.tintColor = nil;
return YES;
}
You are using the outdated (since iOS 3) method of adding the viewcontroller's view to the main UIWindow. That should be looking like this:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
// create properly sized window
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// create instance of root VC and assign to window
MainViewController *vc = [[MainViewController alloc] init];
self.window.rootViewController = vc;
[vc release];
[self.window makeKeyAndVisible];
return YES;
}
The navigationController property of a view controller is ONLY set if it is actually presented from a UINavigationController.
See this writeup for more information: http://www.cocoanetics.com/2012/11/revisited/

UINavigationController — left and right flip animation between pushes and pops when presented via presentViewController

Supposed you've got:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
UIViewController *rootViewController = [[UIViewController alloc] init];
rootViewController.view.backgroundColor = [UIColor whiteColor];
[self.window setRootViewController:rootViewController];
[self.window makeKeyAndVisible];
UINavigationController *modal = [[UINavigationController alloc] initWithRootViewController:[[PTFrontViewController alloc] init]];
modal.modalPresentationStyle = UIModalPresentationFormSheet;
[rootViewController presentViewController:modal animated:YES completion:NULL];
return YES;
}
whereas PTFrontViewController and PTBackViewController view controllers have nothing interesting for sake of this example.
How could you push an instance of PTBackViewController from PTFrontViewController animating as in UIViewAnimationTransitionFlipFromLeft or UIViewAnimationTransitionFlipFromRight?
I am already well aware of these three things:
this is not exactly how you should make use of presentViewController
there is a good reason for UINavigationController's default animation
there are several answers how to "customize" UINavigationController's default animation while pushing and poping, but if you try the code for your self you will notice that when a view controller is presented via presentViewController there are drop shadows and background views that won't get animated correctly
So please answer taking these things in mind. Thank you.
First - forget UINavigationController. If you don't need the default animation, just put a UINavigationBar into your controllers. It will get a little easier.
Second - this is a difficult problem, you can't create such an animation only within the modal controller because the background wouldn't be repainted.
Sincerely, the easist solution I see is too forget the modal controller and just add the view controller as a child of your root controller. Then you can control all the animations but you have to write everything by yourself (including the background fading).

Back button not appearing on UINavigationController

I have a UINavigationController setup in my AppDelegate:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// Add the navigation controller's view to the window and display.
[self.window addSubview:navigationController.view];
[self.window makeKeyAndVisible];
return YES;
}
In my RootViewController I am pushing another view onto the stack:
//Show the deals
DealViewController *dvc = [[DealViewController alloc] initWithNibName:#"DealViewController" bundle:nil];
[self.navigationController.navigationBar setHidden:NO];
[self.navigationController pushViewController:dvc animated:YES];
The view shows up, but there is no back button that is added to my navigation bar. Why is this and how can I resolve it?
Are you setting self.title in RootViewController? Perhaps the UINavigationController doesn't have any text to put on the back button, so it omits it...?
Are you setting hidesBackButton = YES or backBarButtonItem = nil in DealViewController, or does it have a different leftBarButtonItem defined?
Try this:
DetailViewController *detailViewController = [[DetailViewController alloc] init];
UIBarButtonItem *back = [[UIBarButtonItem alloc] initWithTitle : #"Back"
style : UIBarButtonItemStyleDone
target : nil
action : nil];
self.navigationItem.backBarButtonItem = back;
[self.navigationController pushViewController : detailViewController animated : YES];
[detailViewController release];
You must think of the navigation controller as a stack of navigation controllers each controlling one screen full of information.
You instantiate the navigation controller with the
-(id)initWithRootViewController:(UIViewController *)rootViewController
method. You specify the root view controller in this call. Then you add the navigation controller's view as a subview to the window, like you did before.
If you want to show your second screen you push another view controller on the stack by using
-(void)pushViewController:detailViewController animated:YES
method.
Using presentModalViewController to show the naviagtionController. Set the navagitionController bar button like so:
[navigationController.navigationBar.topItem setLeftBarButtonItem:
[[[UIBarButtonItem alloc] initWithTitle: #"Back"
style: UIBarButtonItemStylePlain
target: self
action: #selector(dismisstheModal:)] autorelease]];
This happened to me because in my navigation controller's content controller I had set up some navigation controller behavior in viewDidLoad and in another class that inherits from my content controller, and the one that was being presented, i implemented a viewDidLoad as well, and forgot to call [super viewDidLoad] which thereby caused me to override the base class's viewDidLoad where I was setting up my navigation controller buttons. Oooops.

Can't show a nagivationbar after hiding it

I have the following in the mainwindow.xib
Navigation Controller
List item
Tab bar controller
tabbar
firstViewController
SecondViewController
The entrypoint
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
navController.viewControllers = [NSArray arrayWithObject:tabBarController];
[window addSubview:navController.view];
[window makeKeyAndVisible];
return YES;
}
and now in the first viewcontroller i'm writing
-(void)loadView
{
if(rootAppDelegate==nil)
rootAppDelegate=(tabbarAppDelegate *) [[UIApplication sharedApplication]delegate];
listEmergencyItems= rootAppDelegate.listOfEmergencySectionItems;
self.rootAppDelegate.navController.navigationBarHidden = NO;
[super loadView];
}
and in the second viewcontroller i'm writing
- (void)loadView
{
if(rootAppDelegate==nil){
rootAppDelegate=(tabbarAppDelegate *) [[UIApplication sharedApplication]delegate];
}
listHospitalsItems= self.rootAppDelegate.listOfHospitalsItems;
self.rootAppDelegate.navController.navigationBarHidden = YES;
[super loadView];
}
And on the runtime, when it first loads the first view, i see the navigationbar where i need to navigate into a detail view.
And when i press the second tab bar item, i go to the second view, and the navigation bar gets hidden.
But when i press back on the first tabbar item, i.e. returning to the first viewcontroller. the navigation bar remains hidden.
Any idea?
The navigation bar won't show in the second view because neither view was placed on the navigationcontroller's stack. you want to use something like this in the parent to present a child view instead of overriding loadView
ViewToPresentViewController *myVController = [[ViewToPresentViewController alloc] initWithNibName:#"ViewToPresentViewController"
bundle:nil];
myVController.property = someValue;
[self.navigationController pushViewController:myVController
animated:YES];
[myVController release];
then, as i said previously, you can just use [self.navigationController setNavigationBarHidden:animated:]