I am a little bit confused about navigation controllers. In one navigation controller, a large amount of view controllers are present. I have seen so many examples with one navigation controller. Can we create multiple navigation controllers in iOS and in each navigation controller, can we define a number of view controllers? Is it possible? Please, someone explain this to me and give some real world examples if this is possible. Thanks in advance.
You should look at the sample programs in the Apple documentation. The Navigation controller is a stack which start at the app delegate level. You push view controllers into the stack and pop them out when you are done .... going back to the previous level. You can poptoroot which goes down to the lowest level just above the app delegate.
You have the option to have as many navigation controllers as you have Tabs in a Tab bar. it is not confusing ... Apple has a set of good examples that illustrate them ... Believe the sample about Elements is one.
Related
This question is related to this.
I am using KLHorizontalSelect for showing tab bar with scroll option. I have dragged new 7 View Controller on storyboard. If I select Popular, popular view controller should get displayed.
Any idea/ suggestions on how to get this done?
This is a typical example of view controller containment (where you want one view controller to present other view controllers). Navigation controllers and tab bar controllers are example of built in container controllers. But effective iOS 5, Apple opened up containment for the rest of us.
Please see:
Implementing a Container View Controller in the UIViewController Class Reference.
Creating Custom Container View Controllers in the View Controller Programming Guide.
WWDC 2011 - Implementing UIViewController Containment
By the way, buried in the View Controller Programming Guide is subtle note about those four containment methods:
addChildViewController:
removeFromParentViewController
willMoveToParentViewController:
didMoveToParentViewController:
There are some strange interplay here. I would have thought that we, as application developers, would either just do the add... and/or remove... and that iOS would take care of all of the notifications for us, or that we would have to take care of the will... and did... notifications ourselves. But it's actually half-and-half. So read Adding and Removing a Child very carefully.
I need to have a Tab Bar navigation at the end of a branch in the Navigation Controller, as illustrated basically below. (I am using storyboard for structure, and doing everything else programmatically.)
Is this acceptable and stable? (Xcode seems to have no objections.)
Could I put another Tab Bar nav, inside the initial Tab Bar nav, so there would be 3 tiers:
Nav Controller > Tab Bar > Tab Bar
Thanks for any suggestions and advice.
You can do all of this. Xcode won't object. The various view controllers can all contain each other, and will behave (mostly) as you expect.
You might want to think about whether you should do all of this. The View Controller Catalog makes reference to the fact that tab bars always wrap navigation controllers, not the other way around, and similar statements have appeared in the View Controller Programming Guide.
What's more, the particular view controllers that Apple provides generally have an expected user interface, one that users have grown very accustomed to seeing in other apps. Combining multiple tab bar controllers might break those expectations - hierarchical content like that is generally contained in navigation controllers instead. Consider reading through the Human Interface Guidelines before proceeding with this structure.
I believe you can. Tab bar and Nav controller are both container controller and they can be used to contain any kind of controller: container controller or content controller. Have a look to the ref doc for more info.
Not really AFAIK. But you can use a UITabBar NOT a UITabBarController wherever you want.
See this blog article: http://www.alexmedearis.com/uitabbarcontroller-inside-a-uinavigationcontroller/
I'm trying to develop an app having a tab bar controller with 5 bar items.
All of the items need navigation controllers.
I just wanted to know whether it is possible to reuse the same navigation controller for all the items.
Are there any restrictions or things I need to keep in mind to do this?
Every tab in a UITabBarController should have its own UINavigationController, if you're in need of one that is. You push and pop UIViewControllers onto/off a stack and every UINavigationController has its own stack. Since the UIViewControllers from your other tabs have nothing to do with the navigation flow from the current tab, each tab should have its own UINavigationController.
I think I may have misinterpreted your question originally here... Navigation Controllers actually fine to re-use I think... I'd recommend release and creating a new on when the tab is changed if that makes sense within the application. You could give a reference to it in your appDelegate so it's easily accessible from each view controller.
Original reply follows in case I'm misinterpreting it still :S
The separation is entirely up to you, but for code clarity it's nice to have each viewcontroller separate. As a lot of the code will be found in your controller it's quite nice to separate out as much as possible. You can use the same controller, but change it's view property when each item is clicked, but it doesn't really save much and wil make for harder to maintain code...
hi
i am currently working in iphone navigation based application. so my app have 30 screen,after navigating five screen i need a TabbbarController . I add tabbar Controller OverMy viewController ( [self.View addSubView:tab.View];) my application work fine and navigation work perfect but my problem is that after navigating from tabScreen to other myViewController which inside tabbbar controller are not relaods but navigated view controller work fine .
so above my code adding tabbar is wrong then plz help me ,thanks in advance.
I have to say, that I don't fully understand your question, I guess this is due to the language barrier, but maybe you can elaborate your explanation a little more. However, I think that I understood your problem. You want a UITabbarController (respectively it's view) to be a subview of a UINavigationController. Is that correct?
The answer to this question is simple, but, I'm afraid, unsatisfying your you: You can't do that and even if you could, you shouldn't. Please have a look at Apple's excellent ViewController guide. It says:
Thus, a navigation controller can incorporate custom view controllers, and a tab bar controller can incorporate both navigation controllers and custom view controllers. However, a navigation controller should not incorporate a tab bar controller as part of its navigation interface. The resulting interface would be confusing to users because the tab bar would not be consistently visible.
I'm developing an iPhone application and I'm trying to do this:
I want an application with tree views. The view shown first, doesn't have a navigation bar. If the user tap on a button, I need to open the second view with a navigation bar and a table view. The user can also add new items to the table view. If the user do so, the application will show the third view where the user can add fields (this view has also a navigation bar).
It may seem simple, but for me it is not. I don't know how to use the UINavigationController and have not found yet a similar example for what I do (paragraph translated by google).
UPDATE
I don't know how where to put UINavigationController.
How can I do that? Can I use a UIViewController to call a UINavigationController?
Thank you.
take a look at the Recipes example (it also uses core data which may confuse things a little) http://developer.apple.com/iphone/library/samplecode/iPhoneCoreDataRecipes/Introduction/Intro.html#//apple_ref/doc/uid/DTS40008913
There is also a simpler starting point here http://developer.apple.com/iphone/library/samplecode/TableViewSuite/Introduction/Intro.html#//apple_ref/doc/uid/DTS40007318 but the Recipe example covers just about everything you need.
EDIT:added the following
For the very simplest example use XCode to build a new application - a navigation based application (sorry, I'm in front of a PC today so that is from memory). That will give you a blank application with the navigation controller created. You then use the navigation controller to push and pop your view controllers
ViewController Programming Guide