My problem is that I want to have a tab bar view with its children view controllers shown first. In the children view controllers, depending on what controls are clicked, I either want to A) drill down within the tab bar view (swiping away the child view controller) or B) drill down over the tab bar view (swiping away the tab bar view controller).
I've tried solving this problem by wrapping a navigation controller within the children view controllers (so I can drill down using method A) of the tab bar controller and then wrapping another navigation controller around the tab bar controller itself (so I can drill down using method B), hence the title. So it goes:
Window -> UINavigationController -> UITabBarController -> UINavigationController -> child view controller
The problem is that I end up with two navigation bars:
two navigation bars!! http://img527.imageshack.us/img527/240/problemc.png
Has anyone else had this problem, and if so, how did you get around it?
Thanks!
In this case, perhaps you can simply use a UITabBar and programmatically manage its state, without nesting a tab bar controller inside another controller.
If you're using two nested UINavigationControllers I don't think you can work around having two nav bars. You may be able to subclass or method swizzle UINavigationController for the controller whose bar you don't want to show, and somehow prevent it from appearing or being created. You can probably also set the navigation bar's opaque property or hidden property accordingly which may also work, but you would probably need to do some fancy UIView rearranging to prevent empty gaps.
This is purely speculation; i don't know if either approach would work or how they would, but those ideas are what i would get started with were i trying to do this.
Just hide the bar you don't want, easy as this:
[navigationController setNavigationBarHidden:YES animated:NO];
Related
I have a rootViewController that is a UITabBarController. A UIToolBar is present in that controller since it has a SearchBar that is global to the app. In certain tabs, there should be specific UIBarButtonItems, or UISegmentedControl, along with the searchBar. In other tabs, there should be nothing in the toolBar, just a title.
What is a good way to lay out the view? Currently based on what tab is selected, the main toolBar from the rootViewController is either used as it is, have a UISegmentedControl added to it, hidden completely and replaced with another viewController that has its own toolbar, etc. To me, I'm thinking that each viewController that is present in its own tab can have its own ToolBar, and reference the global functionality, vs hiding/showing different toolbars.
sorry if this is a convoluted question. Just wondering if people had experience with this. Thanks.
The short answer is that there isn't really a good way to do this. If you're using a tab bar controller, the tab bar will always be visible along the bottom of your screen. Presumably each tab is a UINavigationController with a navigation bar at the top. There's not an appropriate place to put toolbar buttons in this layout.
A better design could be to abandon the UITabBarController and use a UINavigationController as your root view controller. Instead of tabs, you can have a table view with an item for each view of your application. Then you'll have room for a toolbar at the bottom of the screen. In fact, UINavigationController supports having a toolbar at the bottom. You just override the toolbarItems property to return the items that should appear in each of the child view controllers. You'll just need to set toolbarHidden to NO on the UINavigationController, and you're good to go.
Problem
I have an app with a UITabBarController and four different tabs. Three of these tabs are tables which you can click on each row and it would take you to another view.
Question
How would I implement that in terms of navigation? Should I create a UITabBarController with Navigation Controllers as tabs (as shown in image 1) or with View Controllers as tabs (as shown in image 2) with each View Controller having its own Navigation Controller property?
Image 1:
Image 2:
I tried both but its not working well and its confusing. I'd like to know which is more appropriate so I can focus on that method and then see why it's not working.
The first method you propose is the only method. View controllers have a navigationController property, but it will only return something if your view controller is currently contained within a parent navigation controller.
So to be clear: you should have a UITabBarController which contains your navigation controllers, one navigation controller for each tab that you want to have a navigation hierarchy in.
I am currently developing an app that has a TabBarController and each of the tabs contains a navigation controller. This way on each tab I can show details of the rows selected on a view by pushing the viewcontroller to the navigation controller. Each of the views also have an UINavigationItem above them. In this navigation item I placed a button.
But now I would like to change the viewcontroller for a certain tab, when clicking the button in the UINavigationItem, BUT the view(controller) I want to change to has to act like the root view controller of that tab.
So I do not want to push another view on the navigation controller, but just switch to that view (in the same tab) and have that act as the root view controller.
I cannot find a good way to do this, with actually having the views work correctly. They either do not dealloc when I switch views (which would be nice, because I want to keep memory usage to a minimum).
One way of solving this, might be that I add more tabs to my TabBar Controller and just switch to the right tabs when I click the button, but that would be a last resort.
Not really sure if I described this correctly, but I was wondering what the best way is to do this. My preference is having 3 viewcontrollers and switch between them.
Hopefully I understand your question correctly: you want to basically 'reset' your navigation controller to have a new root.
You can do this by telling your navigation controller that you want to display a new set of view controllers:
[navigationController setViewControllers:[NSArray arrayWithObject:newViewController]
animated:NO];
This will get rid of all view controllers currently on that navigation controller's stack, and reset the root view to newViewController.
I am working with TabBarController application and my requirement is to add a TabBar at the top of the window rather than default bottom. Can somebody help to add the TabBar at the top of the window while using UITabbarController rather than simple tabbar.
I think that is not permitted when using UITabBarController. From the official docs, about tabBar property:
"You should never attempt to manipulate the UITabBar object itself stored in this property. If you attempt to do so, the tab bar view throws an exception. To configure the items for your tab bar interface, you should instead assign one or more custom view controllers to the viewControllers property. The tab bar collects the needed tab bar items from the view controllers you specify.".
I'm trying to write an application that uses a navigation bar and tab bar in what (I'm gathering) is an unusual manner.
Basically, I've got several "pages" ("home", "settings", etc) that each have their own tab. I'd also like to have it so that the "home" page is the root view of the navigation bar, and the other pages are the second-level views of the navigation bar. That is, I should be able to navigate to any page by clicking the appropriate tab bar item, and should be able to navigate to the home page from any other page by clicking the navigation bar's back button.
Currently, I have a UINavigationBar (through a UINavigationController) and a UITabBar (through a UITabController) as children of a UIView. The various pages' view controllers are set as the tab controller's viewControllers property, and the home page's controller is also set as the navigation controller's root view. Each page view's tag is set to its index in the tab control. I have the following logic in the tab controller's didSelectViewController delegate method:
- (void) tabBarController:(UITabBarController*) tabBarController
didSelectViewController:(UIViewController*) viewController
{
if ([navController.viewControllers count] > 1)
[navController popViewControllerAnimated:NO];
[navController pushViewController:viewController animated:YES];
}
Also, in the navigation controller's didShowViewController delegate method, I have the following code:
- (void) navigationController:(UINavigationController *) navigationController
didShowViewController:(UIViewController *)viewController
animated:(BOOL)animated
{
tabController.selectedIndex = viewController.view.tag;
}
The problem that's occurring is that when I run this, the navigation bar, tab bar and home page all display ok, but the tab bar will not respond to input - I cannot select a different tab.
I gather it's more usual to have the tab bar as the child of the navigation control, or vice versa. This doesn't seem to fit my approach, because I don't want to have to individually create the subordinate control each time a change occurs in the parent control - eg: recreate tab bar each time the navigation bar changes.
Does anyone have suggestions as to what's wrong and how to fix it? I'm probably missing something obvious, but whatever it is I can't seem to find it. Thanks!
EDIT: I'm guessing it has something to do with both controller's trying to have ownership of the page controller, but I can't for the life of me figure out a way around it.
Yikes. You're way out on a limb here. I've learned the hard way that UINavigationController and UITabBarController aren't very accommodating when you try to use them in nonstandard ways. UINavigationBar and UITabBar weren't designed to coexist as siblings in the view hierarchy. They really want to be distant cousins. Maybe the approach you're pursuing can be made to work somehow, but I personally wouldn't even attempt it.
With that said, I'll suggest one thing you can check, and then I'll tell you how I'd approach the problem.
Have you implemented, and are you returning YES from tabBarController:shouldSelectViewController: in your UITabBarControllerDelegate? If not, that would prevent your tabs from switching.
Assuming that won't solve all your problems, here's what I would do to get the behavior you're seeking:
Create a UITabBarController and set its view as the root view of your window.
Have a separate UINavigationController under each tab, each with its own navigation bar. (This is the standard way to use UINavigationController and UITabBarController together.)
Set a UITableViewController that displays an identical copy of your main menu table as the root view controller for each navigation controller.
When a row is selected on your "Home" view controller, switch to the associated content tab.
Set a delegate on your UITabBarController. In its tabBarController:didSelectViewController method, call pushViewController:animated:. This is similar to what you're currently doing, except you'll be calling it on (UINavigationController *)tabBarController.selectedViewController.
In the viewDidAppear:animated: of the root view controllers of your content tabs, switch to the "Home" tab. This way, when the user hits the back button to go back to "Home", it will switch to the right tab. (You may also need conditional code to prevent this from happening when the user first selects a content tab. I'm not sure.)
I'll be curious to know if Apple accepts this nonstandard behavior. Come back and let us know. Also, let us know if you get your approach working somehow.