P.S: Please do not suggest me to go with the app delegate way as I will use that in the middle of my app views. Thanx.
I try to use a UINavigationController to display a UITableView like the settings app. So I am trying to start step by step. So far, I try to show up a view contained in a view controller in the navigation stack. But I am missing something somewhere.
Here is my relevant code:
.h file:
#interface ViewController : UINavigationController{
UINavigationController *navigationController;
UIViewController *viewController;
}
#property(nonatomic, strong)IBOutlet UINavigationController *navigationController;
#property(nonatomic, strong)IBOutlet UIViewController *viewController;
#end
.m file :
#implementation ViewController
#synthesize navigationController;
#synthesize viewController;
- (void)viewDidLoad
{
[super viewDidLoad];
//Do any additional setup after loading the view, typically from a nib.
self.viewController = [[UIViewController alloc]init];
self.navigationController = [[UINavigationController alloc] initWithRootViewController:self.viewController];
[self.navigationController.view addSubview:self.viewController.view];
}
**The xib file:**
When I run the app, I am expecting to see the blue view, but all I see is the default blue navigation bar, without even the "Root View Controller" title message.
If you connect UI from IB, try to delete these line (delete alloc, init)
// self.viewController = [[UIViewController alloc]init];
// self.navigationController = [[UINavigationController alloc] initWithRootViewController:self.viewController];
// [self.navigationController.view addSubview:self.viewController.view];
This link Should help you. You might want to go through this to shed better light on the problem you're having.
https://developer.apple.com/library/ios/#documentation/iPhone/Conceptual/SecondiOSAppTutorial/Introduction/Introduction.html
Related
I'm not using a storyboard or anything. I'm just creating the cocoa classes and linking them up individually. I can get to load up the default View Controller which is SplashViewController but i can't get past there.
I have experience in php, android programming and python, but i'm totally clueless on how Obj-C and how the iOS framework works :(
SplashViewController.m
-(void)initializeInterface
{
//Initialize start button
[self.startButton addTarget:self action:#selector(startActivity) forControlEvents:UIControlEventTouchDown];
//Initialize fading backgrounds
[self animateImages];
}
-(void)startActivity
{
PhoneViewController *phoneView = [[PhoneViewController alloc] initWithNibName:#"PhoneViewController" bundle:nil];
[self.navigationController pushViewController:phoneView animated:YES];
}
SplashViewController.h
#import <UIKit/UIKit.h>
#import "PhoneViewController.m"
#class PhoneViewController;
#interface SplashViewController : UIViewController
#property (strong, nonatomic) PhoneViewController * phoneViewController;
#property UIImage *splashbg1;
#property UIImage *splashbg2;
#property (nonatomic, retain) IBOutlet UIImageView *splashbg;
#property (nonatomic, retain) IBOutlet UIButton *startButton;
-(void)initializeInterface;
-(void)animateImages;
-(void)startActivity;
#end
EDIT
classAppDelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
//Move from delegate view controller to root view controller
self.window.rootViewController=[SplashViewController new];
[self.window makeKeyAndVisible];
return YES;
}
Wrap your splash view controller in a navigation controller.
Otherwise, the navigationController property of your splash view controller is nil and pushViewController has no effect.
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController: splashViewController];
To move from one UIViewController to other UIViewController, you can try the following things
If SecondViewController *secondViewController is the UIViewController you want to move in to, then your can do the following:
[self presentViewController: secondViewController animated:YES completion:nil];
This is when you UIViewController is not embedded inside a UINavigationController.
It is possible to create your view controllers entirely in code without using Storyboards or XIB files, but it's not recommended. It's like trying to write a complex user application in assembler. The state of the art has evolved since the days when that was necessary. There are better tools. Use them.
Creating everything yourself is both quite complex and not very well documented. You are setting yourself up for a very frustrating, error-prone process. I've been doing iOS development pretty much full time since 2009, and I would not attempt this.
That being said, if you are a masochist, you would create your view controller using initWithNibName:bundle:, passing in nil for both parameters, and then implement the loadView method. In loadView you're create your view hierarchy and install it.
If you are new to iOS/Objective-C, DO NOT DO THIS. It is like trying to write a kernel device driver in machine code as your first foray into UNIX.
Change you AppDelegate method as below -
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.window.backgroundColor = [UIColor whiteColor];
UINavigationController *navcon = [[UINavigationController alloc]initWithRootViewController:[SplashViewController new]];
//Move from delegate view controller to root view controller
self.window.rootViewController=navcon;
[self.window makeKeyAndVisible];
return YES;
}
Problem in your code, you have not taken any navigationController, that enables you push or pop UIViewController. Doing above you can use your method -(void)startActivity to Start a new ViewController.
I'm creating an application that has 2 main view controllers at the moment. The app loads into the initial viewController, and clicking a button inside should bring up the second viewController. Here's what I have:
AppDelegate.h
#import <UIKit/UIKit.h>
#import "ViewController1.h"
#interface AppDelegate : UIResponder <UIApplicationDelegate>
#property (strong, nonatomic) UIWindow *window;
#property (strong, nonatomic) ViewController1 *mainViewCtr;
#property (strong, nonatomic) UINavigationController *navigationController;
#end
AppDelegate.m
- (void)applicationDidFinishLaunching:(UIApplication *)application {
_mainViewCtr = [[ViewController1 alloc] initWithNibName:#"mainViewCtr" bundle:nil];
_navigationController = [[UINavigationController alloc] initWithRootViewController:_mainViewCtr];
_window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
_window.rootViewController = _navigationController;
_navigationController.delegate = self;
_navigationController.navigationBarHidden = YES;
[_window addSubview:_navigationController.view];
[self.window makeKeyAndVisible];
}
and my button method inside viewcontroller1:
- (IBAction)SessionNickNameSubmit:(id)sender {
ViewController2 *secondViewCtrl = [[ViewController2 alloc] initWithNibName:#"secondViewCtrl" bundle:nil];
[self.navigationController pushViewController:secondViewCtrl animated:YES];
}
but when I click the button the view doesn't change. I tried debugging and the code is hit, but nothing happens.
am I missing a setting somewhere?
UPDATE
I've updated all viewController variable names:
instead of ViewController1/2 I'm using mainViewCtrl and secondViewCtrl
but still no use :(
You made a typo:
it's
_window.rootViewController = _navigationController;
not
_window.rootViewController = _joinViewController;
And NeverHopeless's suggestion is also spot on. It's probably the typo AND the fact that you add your second viewcontroller as ViewController2 and not using a proper variable name.
Another suggestion is making a storyboard (if you are not using one) and adding a segue for the transition. Simply assign the segue processing to the button. Like this:
-(IBAction)SessionNicknameSubmit:(id)sender
{
[self performSegueWithIdentifier:#"identifier" sender:self ];
}
Here is a nice description of how it works and how to use it plus some useful pointers!
Obj-C is a case sensitive language, class name and instance name should not be the same like ViewController2. Try like this:
- (IBAction)SessionNickNameSubmit:(id)sender {
ViewController2 *viewController2 = [[ViewController2 alloc] initWithNibName:#"ViewController2" bundle:nil];
[self.navigationController pushViewController:viewController2 animated:YES];
}
The reason is that you have set the window's rootViewController to ViewController1.
You need to set you navigation controller to the window's rootViewController.
So that when you try to access the self.navigationController on the press of the button, it will access the navigation controller in which the self resides i.e. your window's rootViewController now.
Then it will push the next view controller properly.
After looking at almost every tutorial and every stack overflow answer, I finally found a solution that worked. I had to make an instance of the storyboard in the app delegate and use that to create my first view controller instance.
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
self.storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
self.joinViewController = [self.storyboard instantiateViewControllerWithIdentifier:#"ViewController1"];
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:joinViewController];
_window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
navigationController.navigationBarHidden = YES;
_window.rootViewController = navigationController;
[_window addSubview:navigationController.view];
[self.window makeKeyAndVisible];
return YES;
}
I think the problem was that when I was creating an instance of ViewController, it was creating a new instance and binding the navigation controller to it (independent of the view controller that was showing up in the simulator). So when I was using the push method it wasn't recognizing self.NavigationController (that's why NSLog(self.NavigationController == nil) was logging 1
In my app I am using storyboard, I need to change the title on a viewController. I am doing it as follows. In the .h file:
#property(weak, nonatomic) IBOutlet UINavigationItem *navBar;
And in the .m file:
#synthesize categoriaDescription,navBar;
...
- (void)viewDidLoad
{
[super viewDidLoad];
NSString *category = self.categoriaDescription;
NSLog(#"Value of category = %#", category);
[self.navBar setTitle:category];
...
The default title is not changed, it should be 'A', the value of 'category' in this case. The Log shows 'A'.
Any help is welcome.
Why don't you simply use NavigationController?
realize that viewController.navigationItem does not have any sense if the viewController does not belongs to the navigationController's stack
[self.navigationController setTitle:#"myTitle"];
This should work.
EDIT:
If you do not have a navController on your storyboard
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:self];
[navController setTitle:#"myTitle"];
[self.view addSubview:navController.view];
I have a project which I don't really understand the views and navigation behind. I start out in the AppDelegate (MAAppDelegate), where I define properties:
#property (strong, nonatomic) UIWindow *window;
#property (strong, nonatomic) UIViewController *detailViewController;
Then in the MAAppDelegate.m, I create a navigationController, and
#implementation MAAppDelegate
#synthesize detailViewController;
#synthesize window;
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Init the navController for the Master Detail View of the grade cells
UINavigationController *navController = [[UINavigationController alloc] init];
detailViewController = [[UIViewController alloc] init];
UIViewController *viewController = [[MAController alloc] init];
navController = [[UINavigationController alloc] initWithRootViewController:viewController];
self.window.rootViewController = viewController;
[self.window makeKeyAndVisible];
return YES;
}
So at this point, I think I have a working naviationController, I've setup an instance of a custom UIViewController (custom class MAController) and I've set it up as the rootViewController.
Then, in my MAController class, the class where I do all of my UI stuff (the entire UI is done programmatically, no nibs or storyboards). Here is a bit of the viewDidLoad of MAController:
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view.
[self.navigationController setNavigationBarHidden:YES]; // I commented this line out and realized it does nothing
I go on (in viewDidLoad) to add a bunch of subviews to self.view, like this
[self.view addSubview:self.backgroundImageView];
Earlier, I created a viewController in the AppDelegate class and it was called view, so I assumed it was refereeing to that but now since I've changed it (in AppDelegate) to viewController, I guess I was thinking wrong?
And then finally, I create a UIView in 'viewDidLoad`:
UIView *header = [[UIView alloc] initWithFrame:headerFrame];
header.backgroundColor = [UIColor clearColor];
self.tableView.tableHeaderView = header;
and start adding a bunch of subviews to this new UIView I created header.
So, in short, I have no idea what is happening. Later, when I tried telling (from a method inside MAController) self.navigationController (which I assumed to be navigationController in charge of everything in my project - created at the beginning in the AppDelegate) to pushViewController a new viewController that I was going to use as a detailView for a table, it got weird.
So I'm just trying to understand what has control, and what the rootViewController is, and just what is happening.
The main window root is set to a view controller and not the navigation controller
Change:
self.window.rootViewController = viewController;
to:
self.window.rootViewController = navController;
EDIT:
You can access the navigationController from anywhere by asking your appDelegate. It is normally not considered a good practice:
MAAppDelegate *delegate = (MAAppDelegate *)[[UIApplication sharedApplication] delegate];
UINavigationController *nav = delegate.navigationController;
Don't forget to:
#import "MAAppDelegate.h"
First, take a little time and read through how navigation controllers work. The documentation is really helpful:
https://developer.apple.com/library/ios/documentation/uikit/reference/UINavigationController_Class/Reference/Reference.html
Second, your problem is that your window's root view controller is not the navigation controller you created. Rather it is an instance of MAController. This is what you're doing:
UIViewController *viewController = [[MAController alloc] init];
// some other code ...
self.window.rootViewController = viewController;
I think you meant to add MAController as the root view controller of the navigation controller and make the navigation controller your window's root. If so, you'll want to set your view controllers up like this:
UIViewController *viewController = [[MAController alloc] init];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:viewController];
self.window.rootViewController = navController;
Another potential problem is that you don't seem to be doing anything with your detailViewController. Maybe that's confusing you too.
I'm normally just use storyboard for my iOS, but needed to integrate an SDK which does not use storyboard, rather xib. My initial view controller is from storyboard, and when a button is pushed (IBAction), I would like it to go to the xib view controller, but not sure how programmatically to do so. Here is my AppDelegate:
//AppDelegate.m
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:...{
// set to storyboard on launch
UIStoryboard *mainStoryboard = [UIStoryboard storyboardWithName:#"iPhoneStoryboard"
bundle: nil];
UIViewController* viewController = [mainStoryboard instantiateInitialViewController];
[self.window setRootViewController:viewController];
[window makeKeyAndVisible];
return YES;
}
Here is my code .h:
//mainVC.h
#import <UIKit/UIKit.h>
#interface MainVC : UIViewController{
UIWindow *window;
UINavigationController *navigationController;
}
#property (nonatomic, retain) IBOutlet UIWindow *window;
#property (nonatomic, retain) IBOutlet UINavigationController *navigationController;
#property (nonatomic, retain) IBOutlet UIButton *buttonScan;
-(IBAction) ActionScan;
#end
And the .m:
//mainVC.m
#interface MainVC ()
#end
#implementation MainVC
#synthesize window;
#synthesize navigationController;
#synthesize buttonScan;
- (IBAction)ActionScan{
window.rootViewController = navigationController;
[window makeKeyAndVisible];
}
create instance of your xib viewController with initWithNibName
MyViewController *controller = [[MyViewController alloc] initWithNibName:#"MyViewController" bundle:nil];
& then push this controller instance on navigation controller
[self.navigationController pushViewController:desController animated:YES]
In the view controller in storyboard, code below:
alloc & init destination view controller:
UIViewController *desController = [[SomeViewController alloc]init];
show the destination view controller:
[self.navigationController pushViewController:desController animated:YES]
or
[self.navigationController presentViewController:desController animated:YES completion:nil
Usually you don't set the window's rootViewController directly. Instead you should use
- (IBAction)ActionScan{
[self presentViewController:self.navigationController animated:YES completion:nil];
}
to show your next view controller. The first and accepted answer to this question gives a more detailed explanation of how this works.
Changing root view controller of a iOS Window
Setting window.rootViewController and calling [window makeKeyAndVisible] usually happens in your app delegate, but since you're using storyboards, it is done for you under the hood.
Also, unless you're using multiple windows, you can access your UIWindow from anywhere using your app delegate singleton object.
MyAppDelegateClass *appDelegate = (MyAppDelegateClass*)[[UIApplication sharedApplication] delegate];
UIWindow *mainWindow = appDelegate.window;