I read that it is bad to have such structure in an iOS application. But what if an application has a lot of UINavigationControllers and UITabBarControllers. But one UINavigationBar and one UITabBar are always displayed only? Other UINavigationBars and UITabBars are hidden.
EDITED
For example, in navigation-based application I call this code:
- (IBAction)openTabsController:(id)sender {
tabOneController *tabOneViewContr = [[[tabOneController alloc] initWithNibName:#"tabOneController" bundle:nil] autorelease];
UINavigationController *tabOneNavContr = [[UINavigationController alloc] initWithRootViewController:tabOneViewContr];
tabTwoController *tabTwoViewContr = [[[tabTwoController alloc] initWithNibName:#"tabTwoController" bundle:nil] autorelease];
UINavigationController *tabTwoNavContr = [[UINavigationController alloc] initWithRootViewController:tabTwoViewContr];
UITabBarController *tabContr = [[[UITabBarController alloc] init] autorelease];
tabContr.viewControllers = [NSArray arrayWithObjects:tabOneNavContr,tabTwoNavContr, nil];
sel.navigationController.navigationBar.hidden = YES;
[self.navigationController pushViewController:tabContr animated:YES];
}
After calling of this method I have two UINavigationControllers and one UITabBarController. At the same time I have one UINavigationBar and one UITabBar on a screen.
EDITED
Approximate scheme.
From The beginning we have an UINavigationController which allows to navigate between the views (circles). Then after pushing an UITabBar appears and allows to switch between the views. A rectangle with two little rects is a view with a UITabBar with 2 UITabBarItem s. When we presss any UITabBarItem another UIView appears. In this UIView we can press some button which calls another view with another UITabBar. Current UITabBar is visible after pushing if it is not hidden with another UITabBar.
is it more clear now?
The code above works almost perfect (except of some animations and not including Apple's limitations)
Gargo,
I'm not sure I understood your question but the apple documentation is clear. If you use - (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated it says that viewController:
cannot be an instance of tab bar controller and it must not already be
on the navigation stack.
Since you do
[self.navigationController pushViewController:tabContr animated:YES];
you are pushing a tab bar controller instance within the navigation stack.
If you add the structure that you would achieve maybe I can help you to find another solution.
Hope that helps.
An app should only have one working tabBarController at any one time.
A tabBarController should also be the root view controller. Always. (If you need a login view or similar before the tabBarController, then remove the login view, create the tabBarController and then make that the root).
This is Apple' advice spoken to me personally by Apple engineers.
Remember, apps should be small applications that are quick and easy to use/navigate. If you feel the need for more than one tabBarController then your app design is likely very wrong from a UI/Usability perspective.
Related
So, I'm programming a universal application, and with iOS 8, it seems easiest to create split views to ensure that everything properly appears on iPhones and iPads. The dominant UI component in my app is a tab bar.
One of my tabs is a tableview that acts as a menu. I want to push a split view controller from didSelectRowAtIndexPath like so:
[self.navigationController pushViewController:ytSplitViewController animated:YES];
This returns an error: Split View Controllers cannot be pushed to a Navigation Controller
I can modally present the view controller, but this hides my tab bar and makes my interface more convoluted (an undesirable result)
[self.navigationController presentViewController:ytSplitViewController animated:YES completion:nil];
Is there a workaround that I can employ to present my SplitViewController within my UI paradigm? More clearly, can I essentially push my split view controller using a different method?
In case it's relevant, this is how I create my split view:
YTTableViewController *ytTableViewController = [YTTableViewController new];
UINavigationController *ytNavigationController = [[UINavigationController alloc] initWithRootViewController:ytTableViewController];
YTDetailViewController *ytDetailViewController = [YTDetailViewController new];
UINavigationController *ytDetailNavigationController = [[UINavigationController alloc] initWithRootViewController:ytDetailViewController];
NSArray *ytViewArray = [NSArray arrayWithObjects:ytNavigationController, ytDetailNavigationController, nil];
UISplitViewController *ytSplitViewController = [UISplitViewController new];
ytSplitViewController.viewControllers = ytViewArray;
ytSplitViewController.delegate = ytDetailViewController;
Split view controllers are meant to be presented as root objects, not pushed in the hierarchy.
Of course, you can always trick it, by using view controller containment. Create a UIViewController subclass, add the split view controller as a child controller, and push the parent controller. This should work.
I have an application that has a UITabBarController created in IB. That tbc loads 3 views which work fine up to now.
I decided to INSERT a UINavController as the starting VC and have a UITableViewController display 4 menu items in cells. Each of the 4 items will in essence load the UITabBarController put pass in a different xml file to process in order to display data in those 3 tabs.
I essentially did this at the end of the applicationDidFinishLoading:
MainMenu *rootViewController = [[MainMenu alloc] init];
navController = [[UINavigationController alloc] initWithRootViewController:rootViewController];
self.window.rootViewController = navController;
[window makeKeyAndVisible];
return YES;
I then created the MainMenu as the rootViewController subclassing UITableViewController and added a hardcoded array for now which displays the 4 items I want. I had the didSelectRowAtIndexPath run this code:
tabBarController = [[UITabBarController alloc] init];
[self.navigationController pushViewController:tabBarController animated:YES];
[tabBarController release];
It turns out that when I run it, the navcontroller pushes the tab controller but only the first tab shows up. Here is a pic.
You should never push a UITabBarController from a UINavigationController. Apple clearly says this:
An app 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.`
That essentially means tab bar should be the parent of all other view controllers that get called. Not the other way round. You should probably change the way you present your app.
More information here.
Preface: I am not using *.xib files.
I instantiate a UINavigationController in a class that effectively serves as my 'rootViewController'. This 'rootViewController' also has two UITableViewController members that are drawn on different sections of the iPad screen. One of which is set as the root view for the navigation controller. Let's call it tableViewControllerA.
The problem is, when I invoke pushViewController on a valid UINavigationController, I see no effect:
[tableViewControllerA.navigationController pushViewController:tableViewControllerX animated:YES];
I've gathered from the posts I've searched today, that this push method should in turn cause the screen to redraw the top of stack controller.view. This is not what I'm seeing.
It seemed there was a disconnect in my implementation, and it was time to reference a working example in my environment (xcode 4.0). Assuming the canned templates would provide a working basis, I created a new navigation-based applications. I simply modified didFinishLaunchingWithOptions: as follows.
UIViewController *view1 = [[UIViewController alloc] init];
UIViewController *view2 = [[UIViewController alloc] init];
view1.title = #"view1";
view2.title = #"view2";
[self.navigationController pushViewController:view1 animated:YES];
[self.navigationController pushViewController:view2 animated:YES];
self.window.rootViewController = [[UINavigationController alloc] initWithRootViewController:view1];
[view1 release];
[view2 release];
I found similar results. When I launch the simulator the screen title reads the title of whatever the self.window.rootViewController is pointing at. With the code as is, the title of the resulting top screen reads "view1". When I initWithRootViewController:view2, the resulting top screen reads "view2".
So please tell me I'm stupid cuz xyz...
Thanks.
Here are some references and suggestions:
Simple tutorial for navigation based application:
http://humblecoder.blogspot.com/2009/04/iphone-tutorial-navigation-controller.html
Here is another one to create the step by step navigation controller and adding the views:
http://www.icodeblog.com/2008/08/03/iphone-programming-tutorial-transitioning-between-views/
and here a bit advance with navigation + tab bar controller:
http://developer.apple.com/library/ios/#featuredarticles/ViewControllerPGforiPhoneOS/CombiningToolbarandNavigationControllers/CombiningToolbarandNavigationControllers.html
Without seeing your code, I have 2 theories:
Your syntax and calls are wrong when you do the push. Use this as a model:
-(void)Examplemethod {
AnotherClassViewController *viewController = [[[AnotherClassViewController alloc] initWithNibName:#"AnotherClassView" bundle:nil] autorelease];
[self.navigationController pushViewController:viewController animated:YES];
}
You are never adding the navigation controller to the view hierarchy which never adds the view either. Take a look at this.
I'm starting out with iOS Development.
Currently, I've implemented a TabBarController that nests 2 Views, one of which has a TableView within in.
I'm trying to get the table view to Push another view when DidSelectRow is called.
What I am trying to do is similar to the AppStore in the Search Tab.
I.E:
When you find the App you want you tap on the table row - then the search bar fades away and the Navigation bar fades in, revealing more detail.
Right now I'm trying this:
self.nav = [[UINavigationController alloc] initWithRootViewController:rootVC];
nav.delegate = self;
self.detailView = [[detailView alloc] initWithNibName:#"detailView" bundle:nil];
[nav pushViewController:self.detailView animated:YES];
Where rootVC is the viewController in my secondView.
This does nothing. I've called NSLog to make sure that the method is being called, and it is.
Any help is greatly appreciated.
Thanks!
Do you have a navigation controller in the app? One way to achieve the navigation controller with tab bar controller is to add navigation controller for each tab bar item . Then make the root view controller of the navigation controller one of your 2 views controllers.
I am trying to display a UISplitViewController presenting it as a Modal View Controller in my iPad app. I manage to have it display, but for some reason there is a gap to the left of the modal view the size of a Status Bar which is also preserved when the orientation is changed.
Does anybody know why this is happening? Or if this is even possible? Maybe I'm just digging myself a huge hole.
Like for many of you, I needed a 'modal way' to use the UISplitViewController. This seems to be an old issue, but all I found in StackOverflow was at best an explanation why the problem happens when you attempt to do so (like the accepted answer above), or 'hack-arounds'.
However, sometimes it is also not very convenient to change much of your code-base and make a UISplitViewController the initial object just to get it's functionality up and running.
In turns out, there's a way to make everybody happy (including Apple guidelines). The solution that I found best, was to use the UISplitViewController normally, but when needed to be shown/dismissed, use the following approach:
-(void)presentWithMasterViewController: (UIViewController *) thisMasterViewController
andDetailViewController: (UIViewController *) thisDetailViewController
completion:(void(^)(void))completion
{
masterViewController = thisMasterViewController;
detailViewController = thisDetailViewController;
[self setViewControllers:[NSArray arrayWithObjects:masterViewController, detailViewController, nil]];
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
self.window.autoresizingMask = UIViewAutoresizingFlexibleWidth|UIViewAutoresizingFlexibleHeight;
self.window.rootViewController = self;
[self.window makeKeyAndVisible];
if(completion)
completion();
}
-(void)dismissViewControllerWithCompletion:(void (^)(void))completion
{
self.window = nil;
masterViewController = nil;
detailViewController = nil;
if(completion)
completion();
}
Where "window", is a property of your UISplitViewController subclass. And the system will take care of the rest!
For convenience/reference, I uploaded this as a UISplitViewController subclass to gitHub:
ModalSplitViewController
--EXAMPLE ON HOW TO USE --
mySplitViewController = [[ModalSplitViewController alloc] init];
mySplitViewController.delegate = self;
[mySplitViewController presentWithMasterViewController:masterViewController andDetailViewController:detailViewController completion:nil];
// when done:
[mySplitViewController dismissViewControllerWithCompletion:nil];
mySplitViewController = nil;
Side-note: I guess most of the confusion originates from the fact that
the UISplitView usage example from Apple documentation uses the window
created in the appDelegate, and for the fact that most people are not
so familiar with the window concept - because we normally don't need
to (they are created once in StoryBoards or boilerplate code).
Additionally, if you are doing state restoration, one should not
forget that programmatically-created UIViewControllers won't
automatically be restored by the system.
The stock UISplitViewController was designed for use as the root view controller only. Presenting one modally goes against the Apple Human Interface Guidelines and has a high probability of getting rejected by the App Review Team. In addition, you may receive the error:
Application tried to present Split View Controllers modally
Technically, this is what I did:
1/ Subclass a UIViewController ie. #interface aVC: UIViewController
2/ In the viewDidLoad, set up a splitViewController, ie. aSplitVC
3/ Then self.view = aSplitVC.view
After all, present aVC as modalViewController
I agree with Evan that this is slightly off-color for Apple, but I was able to complete a working version of this with the following solution:
UISplitViewController *splitVC = [[UISplitViewController alloc] init];
splitVC.delegate = VC2;
splitVC.viewControllers = [NSArray arrayWithObjects:navcon1, navcon2, nil];
UINavigationController *splitNavCon = [[UINavigationController alloc] init];
splitNavCon.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
[splitNavCon.view addSubview:splitVC.view];
VC2.splitParentViewController = splitNavCon;
[self presentViewController:splitNavCon animated:YES completion:nil];
This allowed me to have a working back button in the new UISplitViewController that was presented modally on the screen.
You'll notice that I actually pass the VC2 (the delegate of the UISplitViewController) its parent UINavigationController. This was the best way that I found I could dismiss the UISplitViewController from within the VC2:
[splitParentViewController dismissViewControllerAnimated:YES completion:nil];
I believe one can do the other way around: instead of custom controller presenting split controller, one can set up the split controller as the root window controller in storyboard, and on top of its view you can add your custom controller (ie, login screen) and remove it from the screen (removeFromSuperview for example) when it is needed.
That answer is not actually correct, because it not valid any longer since iOS8 and if you need to support even iOS7 you can do that like you put actually modally UIViewController which has a container as SplitView.
let mdSplitView = self.storyboard?.instantiateViewControllerWithIdentifier("myDataSplitView") as! MyData_SplitVC
self.addChildViewController(mdSplitView)
mdSplitView.view.bounds = self.view.bounds
self.view.addSubview(mdSplitView.view)
mdSplitView.didMoveToParentViewController(self)