PushViewController doesn't do anything - ios

This is the first time I'm trying to implement navigation from a tableView cell to another tableView using UINavigationController and it doesn't work for me.
I'm NOT using nib file and I have a simple tableView that I present it in a modal dialog in my app, it works fine, now I added the disclosureInidcator to one of it's cell, to make the user enable to choose from a fixed number of options available from another list(tableView). For this purpose I have another class that makes the second tableView. the problem is now navigation from the cell(contains disclosure icon)in first tableview to second tableView doesn't do anything, no error, no nothing. I guess the way I setup the navigation controller would be wrong, the code doesn't fall in delegate, or datasource of the second class at all.
in First TableView in method : didSelectRowAtIndexPath I tried to catch that row, then call the second tableView like this:
mySecondViewController *secondVC = [[[mySecondViewController alloc] initWithStyle:UITableViewStyleGrouped ] autorelease];
UINavigationController *navCont = [[UINavigationController alloc] initWithRootViewController: self];//not sure the first controller should act as the root controller?
[navCont pushViewController:secondVC animated:YES]; //it does nothing, no error,...
the second tableViewcontroller class contains all delegate and datasource methods, and initialization method:
- (id)initWithStyle:(UITableViewStyle)style
{
if ((self = [super initWithStyle:style])) {
}
return self;
}
and declared in interface as:
#interface stockOptionViewController : UITableViewController {
}
I tried to play with viewDidLoad, but didn't help.
Please help me cause I have no clue and all sample codes found is based on using nib files.
Thank,
Kam

Your navigation controller should be the root view controller of the app delegate's window, and the first view controller should be the root view controller of the navigation controller, then you can push new controllers onto it.
Please see the documentation for UINavigationController.
At the moment, you are creating a navigation controller but not putting it anywhere, so asking it to push new view controllers is a little pointless. You have the right code, just not in the right order.

You can present view control modally without nav controller
mySecondViewController *secondVC = [[[mySecondViewController alloc] initWithStyle:UITableViewStyleGrouped ] autorelease];
[self presentModalViewController:secondVC animated:YES];

UINavigationController should be the root view controller. In the current code, navCont is not on the view stack, so it won't work. Instead of pushing myFirstViewController in your appDelegate, push the UINavigationController to the stack and add myFirstViewController as its root view controller.

Related

Add a second UINavigationController

I have my first NavigationController set up with root viewcontroller - PhotoViewController, It's a collectionView with grid of images. When image is selected I wan't to present a second navigationController with root controller - DetailViewControler.
My first navigationController is set up in appDelegate. I really don't understand how and where should I create the second. I'm not using IB. At the moment I have this in my DetailViewcontroller viewDidLoad:
DetailViewController *detailView = [[DetailViewController alloc] init];
self.detailController = [[UINavigationController alloc] initWithRootViewController:detailView];
But when i'm trying to push a new controller, nothing happens. I guess that my code is in wrong place.
When I try to present second controller modally from my PhotoViewController, I have an error(trying to present nil viewController).
The common idea is to have a single navigation VC that contains -- and lets you navigate between -- other VCs. In the situation you describe, you wouldn't create another navigation VC. Instead, create just the detail VC and push that onto the existing navigation VC...
// assuming self is a view controller contained by a navigation controller
self.detailController = [[DetailViewController alloc] init];
[self.navigationController pushViewController:self.detailController animated:YES];
Use a parent view controller as your initial view controller and add the navigation controllers as children, then transition between them. See this blogpost that I wrote: http://sketchytech.blogspot.co.uk/2012/09/container-view-controllers-parent-view.html

Using multiple storyboards with a TabBarController

Okay, so in the process of developing my newest app, I found that my storyboard got huge, so in an effort to clean it up some, i have divided it into multiple storyboards before it gets out of hand. just for settings alone i have roughly 20 tableviewcontrollers that branch out from a root NavigationController. That navigationcontroller was a TabItem on a TabBarController, which is the application's root view controller.
I've moved the TabBar into it's own StoryBoard as the Root_Storyboard and the Navigation controller is now the initial view of the Settings_Storyboard.
Just for testing purposes, I placed a few UIViewControllers as tab items in the TabBarController (Root_Storyboard) and subclassed one and added the following code to it's viewWillAppear method. It works great, but I know that the presentViewController displays the NavigationController modally and hides the tabBar. Obviously I don't want that, how do I get it to push properly so that the TabBar remains visible?
- (void) viewWillAppear:(BOOL)animated {
UIStoryboard *settingsStoryboard = [UIStoryboard storyboardWithName:#"Settings_iPhone" bundle:nil];
UIViewController *rootSettingsView = [settingsStoryboard instantiateInitialViewController];
[self.tabBarController presentViewController:rootSettingsView animated:NO completion:NULL];
}
Edit - To clarify. The above code is the subclassed method for a UIViewController (child of UITabBarController:index(1)) in the Root_iPhone.storyboard. The UINavigationController/UITableViewController that I am trying to load is found in Settings_iPhone.storyboard. Not sure how to implement the linkView suggested below in this situation.
This is quite possible and a smart move - decluttering your Storyboards presents cleaner interface files to dig through, reduced loading times in XCode, and better group editing.
I've been combing across Stack Overflow for a while and noticed everyone is resorting to Custom Segues or instantiating tab based setups programmatically. Yikes. I've hacked together a simple UIViewController subclass that you can use as a placeholder for your storyboards.
Code:
Header file:
#import <UIKit/UIKit.h>
#interface TVStoryboardViewController : UIViewController
#end
Implementation file:
#import "TVStoryboardViewController.h"
#interface TVStoryboardViewController()
#property (nonatomic, strong) UIViewController *storyboardViewController;
#end
#implementation TVStoryboardViewController
- (Class)class { return [self.storyboardViewController class]; }
- (UIViewController *)storyboardViewController
{
if(_storyboardViewController == nil)
{
UIStoryboard *storyboard = nil;
NSString *identifier = self.restorationIdentifier;
if(identifier)
{
#try {
storyboard = [UIStoryboard storyboardWithName:identifier bundle:nil];
}
#catch (NSException *exception) {
NSLog(#"Exception (%#): Unable to load the Storyboard titled '%#'.", exception, identifier);
}
}
_storyboardViewController = [storyboard instantiateInitialViewController];
}
return _storyboardViewController;
}
- (UINavigationItem *)navigationItem
{
return self.storyboardViewController.navigationItem ?: [super navigationItem];
}
- (void)loadView
{
[super loadView];
if(self.storyboardViewController && self.navigationController)
{
NSInteger index = [self.navigationController.viewControllers indexOfObject:self];
if(index != NSNotFound)
{
NSMutableArray *viewControllers = [NSMutableArray arrayWithArray:self.navigationController.viewControllers];
[viewControllers replaceObjectAtIndex:index withObject:self.storyboardViewController];
[self.navigationController setViewControllers:viewControllers animated:NO];
}
}
}
- (UIView *)view { return self.storyboardViewController.view; }
#end
Description:
The view controller uses its Restoration Identifier to instantiate a storyboard in your project.
Once loaded, it will attempt to replace itself in its
UINavigationController's viewController array with the Storyboard's
initial view controller.
When requested, this subclass will return the UINavigationItem of the Storyboard's initial view controller. This is to ensure that navigation items loaded into UINavigationBars will correspond to the view controllers after the swap.
Usage:
To use it, assign it as the subclass of a UIViewController in your Storyboard that belongs to a UINavigationController.
Assign it a Restoration ID, and you're good to go.
Setup:
And here's how you set it up in the Storyboard:
This setup shows a tab bar controller with navigation controllers as its first tab controllers. Each navigation controller has a simple UIViewController as its root view controller (I've added UIImageViews to the placeholders to make it easy to remember what it links to). Each of them is a subclass of TVStoryboardViewController. Each has a Restoration ID set to the storyboard they should link to.
Some wins here:
It seems to work best for modal presentations where the subclass is the root view controller of a navigation controller.
The subclass doesn't push any controllers on the stack - it swaps. This means you don't have to manually hide a back button or override tab behaviour elsewhere.
If you double tap on a tab, it will take you to the Storyboard's initial view, as expected (you won't see that placeholder again).
Super simple to set up - no custom segues or setting multiple subclasses.
You can add UIImageViews and whatever you like to the placeholder view controllers to make your Storyboards clearer - they will never be shown.
Some limitations:
This subclass needs to belong to a UINavigationController somewhere in the chain.
This subclass will only instantiate the initial view controller in the Storyboard. If you want to instantiate a view controller further down the chain, you can always split your Storyboards further and reapply this subclass trick.
This approach doesn't work well when pushing view controllers.
This approach doesn't work well when used as an embedded view controller.
Message passing via segues likely won't work. This approach suits setups where sections of interface are unique, unrelated sections (presented modally or via tab bar).
This approach was hacked up to solve this UITabBarController problem, so use it as a partial solution to a bigger issue. I hope Apple improves on 'multiple storyboard' support. For the UITabBarController setup however, it should work a treat.
This is a bit late for Hawke_Pilot but it might help others.
From iOS 9.0 onwards you can create a Relationship Segue to another storyboard. This means that Tab Bar View Controllers can link to View Controllers on another storyboard without some of the mind-bending tricks seen in other answers here. :-)
However, this alone doesn't help because the recipient in the other storyboard doesn't know it's being linked to a Tab Bar View Controller and won't display the Tab Bar for editing. All you need to do once you point the Storyboard Reference to the required View Controller is select the Storyboard Reference and choose Editor->Embed In->Navigation Controller. This means that the Nav Controller knows it's linked to a Tab Bar View Controller because it's on the same storyboard and will display the Tab Bar at the bottom and allow editing of the button image and title. No code required.
Admittedly, this may not suit everyone but may work for the OP.
Not sure if your question is answered, and for others looking for a solution to this problem, try this method.
Create the Tab Bar Controller with Navigation Controllers in one storyboard file. And add an empty view controller (I named it RedirectViewController) as shown in the picture.
The child view controller (let's call it SettingsViewController for your case) is located in Settings_iPhone.storyboard.
In RedirectViewController.m, code this:
- (void)viewWillAppear:(BOOL)animated
{
UIStoryboard *settingsStoryboard = [UIStoryboard storyboardWithName:#"Settings_iPhone" bundle:nil];
UIViewController *rootSettingsView = [settingsStoryboard instantiateInitialViewController];
[self.navigationController pushViewController:rootSettingsView animated:NO completion:nil];
}
SettingsViewController will be pushed into view instantly when Settings tab is touched.
The solution is not complete yet! You will see "< Back" as the left navigationItem on SettingsViewController. Use the following line in its viewDidLoad method:
self.navigationItem.hidesBackButton = YES;
Also, to prevent the same tab bar item from being tap and causes a jump back to the blank rootViewController, the destination view controllers will need to implement UITabBarControllerDelegate
- (BOOL)tabBarController:(UITabBarController *)tabBarController shouldSelectViewController:(UIViewController *)viewController
{
return viewController != tabBarController.selectedViewController;
}
It works for me.
Add Following code to your LinkViewController
-(void) awakeFromNib{
[super awakeFromNib];
///…your custom code here ..
UIStoryboard * storyboard = [UIStoryboard storyboardWithName:self.storyBoardName bundle:nil];
UIViewController * scene = nil;
// Creates the linked scene.
if ([self.sceneIdentifier length] == 0)
scene = [storyboard instantiateInitialViewController];
else
scene = [storyboard instantiateViewControllerWithIdentifier:self.sceneIdentifier];
if (self.tabBarController)
scene.tabBarItem = self.tabBarItem;
}
Here is the screenShot for LinkViewController .
LinkViewController is just a placeholder where new viewController would be placed. Here is the sample code which I used for my app.
RBStoryboardLink . Its working great for me. Let me know if it is helpful for you.

How can I present a 'standalone' View Controller ('forgetting' the previous one)

I have a regular UINavigationController with a couple of views attached, which are working perfectly fine. Its RootViewController has a custom Menu-button on the top left, at the same place as the "Back"-button is on the attached views. When clicking this menu-button, the menu appears and presents five options.
Obviously, by clicking one of these option, you would be presented with the ViewController for that option.
I want to completely 'forget' the current ViewController, and move on to this new controller. Usually, I would do something like [self presentViewController....]; or [self.navigationController push..];, but in these methods the current ViewController will, I think, always exists 'below' the new presenting viewController (as you would return to this instantiation if using [self dismissViewController..];, I don't want this).
In the presenting ViewController there will be a menu-option to return back to the original controller, but I still want this to be a clean instantiation of it, and not just popping. By thinking ahead in time, I figured I would potentially create an infinite number of ViewControllers on top of each other by using the methods I know of this way.
I entered the world of iOS after the era of ARC began, so I have no clue how to release or deallocate such views, which I assume has relevance here.
The second View Controller is also supposed to be a root in a UINavigationController, and I'm not sure if it's best to use the same UINavigationController, or if I should present a new one, and dismiss the old. Essentially, I would like to replace the Navigation Controller's rootViewController from the rootViewController, but I don't see how that would be possible. Or possibly push to ViewController2, and then popping the rootViewController out of the hierarchy, leaving the new ViewController as the root, but then I assume I'd have problems with the navigational back-button(if it's even possible).
I figured it's just as easy to let ViewController2 be root at its own NavigationController, and presenting this NavigationController from ViewController1. The problem is, I want to completely remove everything that has to do with ViewController1 and its NavigationController from memory after presenting ViewController2, but I have no idea how.
I'm open to other solutions to my situation, but I'd also like an answer to how I can completely 'forget' a view after presenting another on general basis.
If you want to "forget" controllers, you can just replace the window's root view controller with a new one. The original one will be deallocated if you don't have any other strong pointers to it. I'm not sure I understand all of what you're trying to do, but for example, if you want controller 1 and controller 2 to both be root view controllers of a navigation controller, and you don't want controller 1 around when you switch to 2, then do something like this from controller one:
SecondViewController *second = [[SecondViewController alloc] initWithNibName:#"SecondViewController" bundle:nil];
UINavigationController *nav = [[UINavigationController alloc] initWithRootViewController:second];
self.view.window.rootViewController = nav;
This will switch out the controllers, and controller 1 and its navigation controller will be deallocated (assuming that the only thing with a strong pointer to the navigation controller was the window, through its rootViewController property).
Create a menu UIViewController and add it as a root to the UINavigationController on launch. Add 1st UIViewController as a child controller to menu UIViewController when viewDidLoad of menu controller is called. When you click menu to show 2nd UIViewController, remove the 1st UIViewController from menu view controller and add 2nd UIViewController to child of the menu view controller. You can put NSLog in both, 1st and 2nd view controller's dealloc method to check if its released or not. Logic is like this
//inside menuvc class
#interface MenuVC{
UIViewController * currentVC; // current child controller to menuVC
}
-(void)viewDidLoad{
[self addChildController:firstVC]; //to add view controller 1 intially
currentVC = firstVC;
}
-(void)add2ndChildController{
[currentVC removeFromParentViewController];
[self addChildController:secondVC]; //to add view controller 2 when needed
currentVC = secondVC;
}
// dealloc of 1st vc
-(void)dealloc{
NSLog(#"first vc released");
}
I just wrote some sample logic of what I explained before, you have to generalize this logic if you feel its right for you. Hope it helps :)

Setting up a UINavigation controller and various view loads

I have setup a UINavigation controller that uses the AppDelegate as the main point of contact.
I have different methods which run such as presentHomeViewController, presentLoginViewController, which push the different view controllers to the Navigation Controller.
App Delegate - didFinishLaunching
welcomeViewController = [[MyWelcomeViewController alloc] initWithNibName:#"MyWelcomeViewController" bundle:nil];
navController = [[UINavigationController alloc] initWithRootViewController:welcomeViewController];
navController.navigationBarHidden = YES;
self.revealSideViewController = [[PPRevealSideViewController alloc] initWithRootViewController:navController];
[self.revealSideViewController setDirectionsToShowBounce:PPRevealSideDirectionNone];
[self.revealSideViewController setPanInteractionsWhenClosed:PPRevealSideInteractionContentView | PPRevealSideInteractionNavigationBar];
self.window.rootViewController = self.revealSideViewController;
Is this the correct process for this?
- (void)presentHomeViewController {
// We start by dismissing the ModalViewConrtoller which is LoginViewController from the welcomeview
[self.welcomeViewController dismissModalViewControllerAnimated:YES];
// Check if the home view controller already exists if not create one
if (!self.homeViewController) {
NSLog(#"presentHomeViewController- Creating the Home View controller");
homeViewController = [[MyHomeViewController alloc] initWithNibName:#"MyHomeViewController" bundle:nil];
}
// Push the homeViewController onto the navController
NSLog(#"presentHomeViewController");
self.navController.navigationBarHidden = NO;
[self.navController setTitle:#"Home"];
[self.navController pushViewController:homeViewController animated:NO];
If I then add the following to a different class :
[self.navigationController pushViewController:accountViewController animated:NO];
No view is pushed to the stack, should I control all the movement within the AppDelegate as I have been doing, or is there betters way to approach this?
EDIT
Thanks for posting your code. So, to address your final question first, I don't recommend controlling your navigation stack from the app delegate. You should be controlling the stack from the view controllers that are the children of the navigation controller.
To that point, remember the hierarchy of view controllers: UINavigationController inherits from UIViewController, and UIViewController has properties defined for all the things you'd see in a navigation layout such navigation items and title. More importantly, it also has properties for its parent view controllers, the view controller that presented it, and its navigation controller. So, considering the hierarchy, your app delegate should only instantiate the navigation controller's root VC and the nav controller itself, and then subsequently set the nav controller's root VC.
From there, you should be pushing and popping other VCs from the VCs themselves. Remember, every VC has a property that's automatically set to point at the navigation controller it's a part of. That's why [self.navigationController pushViewController:] works. For instance, if I have a nav controller whose root VC is a UITableViewController, and tapping on one of the items in the table view pushed a new VC onto the stack, I would push that VC from the table VC and not from the nav controller class or the app delegate.
Sorry if that's confusing. Please let me know if that needs clarification and I'll give it my best. Otherwise, hopefully that gets you on the right track.

navigation bar not showing with a programmatically made UINavigationController

I have a navigation controller named navController made programmatically in my modal view controller during its viewDidLoad:
self.navController = [[UINavigationController alloc] initWithRootViewController:self];
self.navController.view=self.view;
[self setView:self.navController.view];
But when i launch the modal view controller i dont see the navigation bar, just the standard view i made in IB. Whats wrong?
Your solution cannot work.
Suppose that you have your modal controller called ModalViewController. It's a simple UIViewController linked with a xib created interface.
Now, at some point you need to present ModalViewController modally. As you wrote in your specification, I think you want to use also a UINavigationController and control its navigation bar.
The code to do this could be the following, where presentModally could be a method that it's not contained in ModalViewController.
- (void)presentModally:(id)sender {
ModalViewController *modalController = [[ModalViewController alloc] initWithNibName:#"ModalView" bundle:nil];
// Create the navigation controller and present it.
UINavigationController *navigationController = [[UINavigationController alloc] initWithRootViewController:modalController];
[self presentViewController:navigationController animated:YES completion: nil];
}
Now, within viewDidLoad of your ModalViewController you have access to navigationController property. In this manner you can control navigationController behaviour. For example:
- (void)viewDidLoad
{
[super viewDidLoad];
// the code changes the title for the navigation bar associated with the UINavigationController
self.title = #"Set from ModalViewController";
}
Some notes
To understand how UINavigationController works read UINavigationController class reference
To understand how modal controllers work read Modal view controllers documentation
The code I provided is a simple example and only demonstrative (I've written by hand so check for syntax). You need to make attention to memory management and how to present modal controllers. In particular, as Apple documentation suggests, to present modal controllers you need to follow these steps:
Create the view controller you want to present.
Set the modalTransitionStyle property of the view controller to the desired value.
Assign a delegate object to the view controller. Typically the delegate is the presenting view controller. The delegate is used by the presented view controllers to notify the presenting view controller when it is ready to be dismissed. It may also communicate other information back to the delegate.
Call the presentViewController:animated:completion: method of the current view controller, passing in the view controller you want to present.
Trigger (when necessary) some action to dismiss the modal controller.
Hope it helps.

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