I have the following structure in my app, is this a correct/valid way of doing it?
UINavigationController attached to the window, the rootcontroller in this navigationcontroller is a UIViewController that presents a tableview. When a user taps one of the rows a UITabBarController is pushed on the stack.
This works, however I began to be unsure when I read this:
Because the UITabBarController class
inherits from the UIViewController
class, tab bar controllers have their
own view that is accessible through
the view property. When deploying a
tab bar interface, you must install
this view as the root of your window.
Unlike other view controllers, a tab
bar interface should never be
installed as a child of another view
controller.
This is not recommended, but it should be OK. The aweful Wordpress app also does this. This depends on the design of your app.
I'm not shure about Apple's approval.
The reason why this is not recommended (and thus might not get approved - now or at a later point!) is user confusion.
Users are used to regard the tab bar as top-level navigation. So if dig down using the table and navigation, and then getting a UITabBar, this is horrible for navigation as the user doesn't know what to expect.
The solution here, of course depending on the use case, is a "switch" in the navigation bar or a toolbar. UISegmentedControl would be a natural choice.
Related
Sorry for the vague title!
I am trying to achieve the following functionality: A user is first presented with a UINavigationController containing a UITableView. When the user taps a cell in the table view, I want to push a new view which contains a UITabBarController (that'll stay visible regardless of the currently visible UIViewController) and a UITableView again, that people can again select a cell from and which will then again push to UINavigationController.
If a user selects a tab from the UITabBar, I want the first screen (without the UITabBar) to be the one that users can go back to, not the tab they just came from. Also, if a user selects one of the UITableView items on any of the tabs, I want the back button to go back to the previously displayed screen (as you'd expect with a standard UINavigationController)
I've spent hours trying to find the answer to this and I just can't anywhere! I hope I haven't been too vague or confusing in my explanation.
James.
If your desired UX is confusing to explain here, imagine how your users will feel! I would reconsider the intended design.
From the View Controller Programming Guide:
An application that uses a tab bar controller can also use navigation
controllers in one or more tabs. When combining these two types of
view controller in the same user interface, the tab bar controller
always acts as the wrapper for the navigation controllers. You never
want to push a tab bar controller onto the navigation stack of a
navigation controller. Doing so creates an unusual situation whereby
the tab bar appears only while a specific view controller is at the
top of the navigation stack. Tab bars are designed to be persistent,
and so this transient approach can be confusing to users.
That said, you can probably hack something close to what you are talking about but you'll need to write a bunch of code to handle the navigation using the UITabBarControllerDelegate and UINavigationControllerDelegate methods and keep track of whatever state you need to know where you want to navigate to based on a user action. Odds are you'll end up with something complicated to code, maintain, and worse, use.
I've yet to find an example that does this. A client wants a navigation-based app where two sections (one nav-screen each) need to have a few views, controlled by a tab bar. I'm having difficulty setting up the logic of connecting all of the elements and making sure the flow makes sense (ex. hitting the nav-bar's back button on any of the tabbed views will lead back to the same screen).
I answered a similiar question not long ago (if I understand your question right). This will add a tabbar as a rootcontroller and each tab has its own navigationcontroller.
Right design pattern for tabbed navigation views?
EDIT
From UITabBarController documentation
Because the UITabBarController class inherits from the
UIViewController class, tab bar controllers have their own view that
is accessible through the view property. When deploying a tab bar
interface, you must install this view as the root of your window.
Unlike other view controllers, a tab bar interface should never be
installed as a child of another view controller.
As #Jolly good has mentioned, Apple HIG suggests not to do such implementations.
The only other way I can suggest is to try implementing a custom view controller that looks/behaves like a tabbarcontroller and make use of that.
Another hack I can think of, not sure if it'll work or if its possible, create a tabbarcontrller the usual way and then set the hideBottomBar property, and make the bottom bar visible only when you want it to be visible.
It is possible, despite the documentation that #Jolly good cited.
As a real world example, let me describe a game of mine. It consists of a UITabBarController (UITBC) and UINavigationController (UINC). The "main" window of the game is the Root view of the UINC, and when the game is active, it hides both the tab bar and nav bar to maximize screen real estate (not as necessary for iPad, but still...).
When the game is idle (paused, between rounds, etc.), it pushes the UITBC onto the nav bar. It also tells the UITBC to make a particular VC selected. That allows access to the additional screens (About, Scores, Instructions, Settings, etc.), and the player can navigate using the tab bar. In addition to the additional views on the tab bar is the game controller that simply pops the UITBC from the nav bar to revert to the game view to un-pause, go to next round, etc. (Obviously, the UITBC is cached within the game VC so it can be pushed back when necessary.)
Using this sort of logic, it is possible to mix and match tab bar and nav bar controllers for complex navigation. You can get away with this for games; just make sure that any non-game app follows Apple's HIG so as not to confuse the user.
I hope this helps.
I am using a UITabBarController as well as a UINavigationController on my app.
In my UITabBarController I am using more than 5 items so I automatically get the 'More' item.
I've managed to add a saving procedure so the order of those items will be kept in case somebody changes the order etc.
With 'More' active I get the More navigation controller with the 'Edit' item positioned under my UINavigationController. Both navigation controller are visible. When I click on 'Edit though the More navigation controller disappears and seem to be hiding under my UINavigationController and therefore I can't see/use the 'Done' function to save my new order
What did I miss?
Cheers
It sounds like you have a UINavigationController as the main VC of your app, and a UITabBarController as one of the VC's on its stack.
I believe Apple actively discourages people from doing this in their apps, and so do I. It is never done in the iOS itself, and I have never seen it in any third-party apps either, so users will probably be confused.
I think you should embed the UINavigationController inside the UITabBarController instead of the other way around, or you could just choose to use another way of showing what you want to show.
I believe iOS does use both navigation controller and tab controller at the same time in their iPod app. The navigation controller takes you to the playing song and back and at the same time you have the tab controller when you select songs/albums/playlists etc. However, the navigation controller (or tab bar controller) seems to be custom made as it handles the More->Edit case by hiding the navigation bar underneath the Edit bar, which is not what the default UITabBarController does.
All in all, I see Apple is rather "creative" when it comes to UI design. For example, in the email app, "New" button is in the lower right corner (bottom bar) while in the SMS app the "New" button is in the upper right corner (navigation bar). I think they pretty much make custom UI to fit the individual needs of the app instead or rigidly following some consistent design.
I am sure this is very simple, yet I am stuck...
I have created an application and added UITabViewController (dragged in from the library in Interface Builder. My application has 3 different views, clicking on appropriate tab brings the different view. So far so good.
I want to convert one of the views to be a UINavigationController: basically a table with the option to delete rows (so UINavigationController would need to have a button "Edit" on top).
I saw many samples which would do either 1 or 2, but not both.
How would I combine it, keeping in mind that I have used provided UITabViewController and did not added UITabBar directly to the view.
Thanks
If you are using Interface Builder, you should be able to just drag and drop a navigation controller into your tab bar controller as a child controller. The next tab bar item should be generated for it automatically from that.
You can also do this programatically by just creating however many UINavigationControllers you need in an array and assigning that to the uitabbarcontroller appropriately.
I actually don't like this method of combining the UINavigationController and UITabBarController since the tab bar controller must always be visible, which can be really confusing sometimes.
Instead, I recommend you make your own custom UITabBarController (Tab bar controller inside a navigation controller, or sharing a navigation root view) which you add to the navigation controller. I personally don't know why Apple didn't do this; hopefully this is the standard way in 4.0 :)
My app features an UITabBarController, which brings up some views.
In the app delegate, I have to pass a (custom) model to it. Is the best way to do so is subclassing, or is there some better method?
If I put the model (e.g. Notes) into my UITabBarController, how do I access it from view controllers?
I'm not really sure why you would want to pass a different model to the UITabBarController. The only thing tab bar controllers do really well is managing the tab bar. Their "model" is basically a list of ViewControllers which they then present to the user if he taps a tab bar icon.
In the documentation Apple says the UITabBarController class is not intended for subclassing, but you could still do this if it were neccessary.
But if you just want to do this because you have convenient access to the tab bar controller from within your other view controllers, then I'd recommend leaving the tab bar controller allone and implementing some sort of a NoteManager class (probably as a singleton) and simply using it from your other view controllers.