iOS - Back button on selecting a tab - ios

I have a UITabBarController. When I select a tab other than the first, I want the tab bar hidden (which I achieved by hidesBottomBarWhenPushed) and the navigation bar to have a back button (not a plain, but default arrowed) (to get to the first tab). How do I achieve this?

I'll answer your question below, but I have to say that this is a very non-standard user interface which is mixing metaphors. If you really want to push to different view controllers, you really should not be using a tab bar. You probably should just have simple buttons to go to your secondary view controllers. I wouldn't be surprised if Apple would reject an app that used a tab bar like the way you're conceiving of it.
Anyway, to answer your question, you don't want to try to add a "back" button to the secondary views, but rather you just want to properly implement a navigation controller. Then, when you push to the secondary views, you get the back button automatically. And you also don't have to worry about silliness associated with hiding the tab bar, because when you push to another view, it will be pushed off, too.
So, consider this example, where you have a tab bar with buttons "One", "Two" and "Three". But, rather than being a proper tab bar controller configuration, you'd have something like this, where "One" is on navigation controller and has a simple tab bar user interface control on it, and if you happen to tap on the second or third tab, it will just push to the respective view. Thus, logically, it might look something like this (even if you're not using storyboards, this might help visualize the potential configuration):
So, on the main view controller ("One"), you'd add a tab bar with an IBOutlet:
#property (weak, nonatomic) IBOutlet UITabBar *tabBar;
I'd then configure that tab bar in viewDidLoad, e.g.:
- (void)viewDidLoad
{
[super viewDidLoad];
self.tabBar.delegate = self;
self.tabBar.selectedItem = [self.tabBar.items objectAtIndex:0];
}
Clearly, the view controller itself would need to be a UITabBarDelegate, and you'd need a didSelectItem that would perform either a push segue or use your navigationController to pushViewController. And, clearly, you will want to change the references to #"Two" and #"Three" with the actual labels you put on your tab bar buttons, but hopefully this gives you the idea:
- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item
{
if ([item.title isEqualToString:#"Two"])
{
// put code for pushing to second view controller here
}
if ([item.title isEqualToString:#"Three"])
{
// put code for pushing to third view controller here
}
}
I'd also want the main view controller to make sure to set the selected item back to the first item when it reappears after you pop back:
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
self.tabBar.selectedItem = [self.tabBar.items objectAtIndex:0];
}
Anyway, if you do it this way, there's no hiding of the tab bar (because it's no longer a controller, but rather just a user interface element on the first tab). This is probably the easiest way to implement your desired user interface.

Related

Can't get default UINavigationController back button to work

First, I've read almost all of the questions and answers on the web and SO about navigation bar/back button/title/navigation item etc. I have a navigation controller and view controllers. Nothing fancy. Whatever I do, I can't display a back button when I push a new view controller. Neither via storyboard push segues nor programmatically pushing. My view controller and navigation bar displays correctly, when I tap where where the back button should be, it does work, it pops the view controller, however, it's not displayed.
Before you say, I'll list what I've done:
I've got the navigation controller's Shows Navigation Bar set to yes.
I've set a title to my root view controller inside the navigation controller on storyboard.
I've set a back button title to my root view controller inside the navigation controller on storyboard.
I don't have any custom code involving navigation bar/navigation item/left bar button/right bar button/hides back button/back button item.
I've set a title for my navigation controller.
Whatever I do, my back button doesn't get displayed. When I debug, it's set to nil. I've tried instantiating one but it didn't help either. What am I missing?
Firstly check that the controller you are pushing from and to has a navigation item in the viewer you can set title, back button and prompt for. I have found that depending on how storyboard has created the controller it may or may not have one you can see in the view tree. Setting the back button does not seem to work unless you can actually see one in both controllers in storyboard.
Secondly, and something I only realized recently, is that you set the title for the back button in the controller you are pushing "from" and not in the controller that will be showing when the back button is showing.
e.g. If you have controller A and controller B and you are pushing to B from A: you have to set the label for the back button in the navigationItem of controller A, not in the navigationItem of controller B. You may already know this, but its confusing.
define a property in .h
#property (strong, nonatomic) UIBarButtonItem *backButton;
in viewDidLoad in .m
self.backButton = [[UIBarButtonItem alloc] initWithImage:[UIImage imageNamed:#"backButton.png"] style:UIBarButtonItemStylePlain target:self action:#selector(backButtonPressed)];
self.navigationItem.backBarButtonItem = self.backButton;
and add the method
-(void) backButtonPressed {
[self.navigationController popViewControllerAnimated:YES];
}
oh misread... you don t want a custom button, just the normal one? maybe there is a UIBarButtonSystemItem for back ?? take this instead of a custom image...
checked tintcolor? maybe it s set to clearcolor ??
It was something much simpler. Actually, everything was acting correctly. After some investigation ([[UIWindow keyWindow] recursiveDescription]) I've realized that it was just me who was faulty to set the storyboard's global tint color to the same color with navigation bar. I've explicitly set the tint to white and now the text is seen.

Unable to configure UINavigationBar for view embedded in Tab Bar Controller

I a writing an app (iOS8) that ultimately needs to load a UITabBarController via a segue from a UITableView. For the most part this setup can be done via Storyboards and works as expected, however I would also like to add a UIButtonBarItem to the destination view which is where the problems start.
A setup that works (without a UITabBarController) can be configured as follows
The button uses a "Show" segue to display the final view controller
The second UIBarButtonItems are added by copying over the Navigation Item from the first view controller (How to add buttons to navigation controller visible after segueing?)
If I run this in the Simulator, everything works as expected and I see both the back button and the desired "Add" UIBarButtonItem:
If I then embed the final view controller in a UITabBarController, the UIBarButtonItem I added disappears and so far any changes I have made to the storyboard setup (adding a UINavigationController in between the UITabBarContoller and the last view for example) or attempts to add the UIBarButtonItem programatically don't make a difference:
Is there anyway to get the final setup working with both a UITabBarController and UIBarButtonItems?
I have the same setup in one of my apps and it works fine. Not sure why you are having issues, but I did add a few lines of code in my custom Tab Controller that may help you. I think the issue is that the nav bar from the original navigation controller is still being shown, so subclass UITabBarController and put these lines in viewWillAppear:
-(void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self.navigationItem setHidesBackButton:YES];
[self.navigationController setNavigationBarHidden:YES];
self.navigationController.interactivePopGestureRecognizer.enabled = NO;
}
In my app, the views before the tab bar controller were login/register views, so there was no reason to navigate back to them after entering the tab controller "stack," but I'm sure it won't be difficult to add a back button that accomplishes this. I believe you only need the [self.navigationController setNavigationBarHidden:YES]; line, which only hides the nav bar instead of hiding the back button or disallowing the pop gesture.
I know this is late but I just want to add swift 3 code.
The reason being that the NavigationBarA of the tabBarController is hiding your NavigationBarB that sits in between your tabBarController and the final ViewController. So you just have to set to hide the NavigationBarA
in viewWillAppear of your final ViewController you can add the following (without a need to subclass tabBarController)
self.tabBarController?.navigationController?.setNavigationBarHidden(true, animated: false)

Performing Modal and Push Segue From Tab bar Item press

A little background that I think will help in this question:
I am working on an iOS7 app which basically presents various quotes and allows the user to share these quotes through facebook or twitter. I am implementing this through a tab bar (not a tab bar controller) that I placed at the bottom of the first view controller in the screenshot.
The tab bar's delegate (file owner) is set to be the view controller that it's in. In there I edited the tabbar: didSelectItem: method to handle every button press accordingly. (The first two button presses are just modal segues to twitter and facebook tools.)
Now my question:
Now I am trying to get the third item in the tab bar to cause a segue to the third view controller (upper right). Can I make a tab bar item perform a push segue? How would I go about doing that?
I have been trying to look for a way to do this but seemed to be stumped. I was thinking that maybe this can be done with a tab bar view controller but then I wasn't sure how I could have my original first two tab bar items perform modal segues
Any help would be appreciated
UPDATE:
The two view controllers at the bottom are segued into when the user touches either of the two views in the first view controller (can be ignored for this queston). The third VC (in the top right) I want to be pushed when the user touches the third tab bar item. The bottom two views just display info about quote presented... the top right vc allows the user to enter a new quote and save it.
You only need to connect a segue from the controller with the tab bar to the third controller, and call it manually in the didSelectItem method,
- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item {
if ([item.title isEqualToString:#"Third"]) { // or whatever your title is
[self performSegueWithIdentifier:#"GoToThird" sender:self];
}

Safe way to remove tab bar from UITabBarController in ios

I want to use UITabBarController but I do not need a tab bar because I'm going to switch tabs from the menu in another view controller. I want to remove it as it will be never used. I've created a subclass of UITabBarController and put this code:
- (void)viewDidLoad
{
[super viewDidLoad];
[self.tabBar removeFromSuperview];
}
Is that safe to remove tab bar that way?
Update: Why tab bar controller?
Apple suggests to use standard container view controllers whenever it possible. I'm trying to follow that. My screens workflow is the same as for tabs, except that they are switched by left side menu, not by the tab bar.
When I use a UIViewController and change it's child view controller I've got a lot of problems when autolayouts are not working properly.
The other reason is that I want to use story board, rather then create segues from the code so I can see my app workflow easily.
When you are saying, you don't want to use it, then why to remove it. You can go with a
tabbarcontroller with hidden tabbar. I am switching tabs from the bottom custom bar.
I am doing an app, which has a tababr controller with three items. Instead of using system tab, I am creating a custom view at the footer like tab & have actually set the hidden property of tabbarController's tabbar to YES.
myTabBarController.tabBar.hidden = YES;
Try this code
[app.navigationController.view removeFromSuperview];
[app.tabbarcontroller.view removeFromSuperview];
[app.window addSubview:app.navigationController.view];
[app.navigationController popToRootViewControllerAnimated:YES];

Swap/ Transitioning between views iOS programming

I am a newbie to IOS programming and currently i have a tab bar application with two tabs. I have two questions.
The first tab shows a map, imagine it with some pushpins. There is a button on the navigation bar and when this is clicked i want the map view to to move out and a list view to come in. You can see the UI from the image. The button is called list.
Now when i click list I want this view to go away and the list view to come in. So here are my questions ?
1) How do i do this ? I tried the navigation model but i don't want that because I do not want a back button. I tried to make two different views and just dragged the button to that view but the app crashes. I just want the list button on the nab bar and when clicked the view changes to the list view and the button text changes to map. So now if I click the button again it should go back to the map view and the button changes to list.
2) How do i achieve the animations for this ? Ive seen some app where the page flips around and I've seen some options like reducing the opacity etc but I want to achieve the flip animation.
Thank You for any help I get. I really appreciate it.
Interface Builder can do most of this. Hold down the control key and drag from your map View Controller's UIBarButtonItem titled "List" to your list View Controller, then choose the Action Segue "modal". An arrow appears representing the segue; click on it and use the Attributes Inspector to change the Transition to "Flip Horizontal". Here's a video
Or, you could do this programmatically with presentViewController:animated:completion.
Now to get back to the map from the list, I believe that must be done programatically. Create a method that calls dismissViewControllerAnimated:completion: and make your list View Controller's UIBarButtonItem titled "Map" trigger it.
After reading your comments, I am wondering... if the structure of your app is logically a tabbed app structure (as indeed you refer to it as a 'tab bar application'), shouldn't you consider using the UITabViewController instead of a NavigationController? That is what it is designed to do, after all.
If you do use a TabViewController you should reconsider your desire for flip animation, as that doesn't really make UI-sense for tabs. If you can dispense with the flip animation, TabViewController could be a good way to go and you should at least experiment with that before dismissing the idea. It is also designed to grow... you can incorporate any number of tabs in a tab bar. Check out the apple docs (with pictures!)
You will notice that tabs are at the foot of the screen, whereas your 'tab' navController buttons are in a navbar at the top of the screen. This also helps as your app grows, as it is straightforward - from a UI design point of view and programmatically - to incorporate navControllers as navigation tools within individual tabs. For example, if your map/list flip routine does indeed make sense for this part of you app, you can keep this as a single tab (in it's own navigationController) and add other tabs for other parts of the app...
update
From your comment, you are saying that you are interested in the navController-inside-tabBarController setup. In this case here are some ways to get flip transitions AND no back button..
(1) modal presentation
The easiest way to get what you want is to set up one of your viewControllers (say the map view) to present the other one (the list view) modally.
If in the storyboard:
embed your mapViewController in a navController with a navbar button for navigation to the listView as in your picture
add your listViewController to the storyboard and embed it in it's own navContoller (not the mapViewController's navController). Drag a barButtonItem to this navController and wire it up to an IBAction in listViewController
CTRL-drag from mapViewController's 'list' button to the listViewController to create a segue. Select the segue and in the attributes inspector set the segue type to 'modal', with transition 'flips horizontal' and 'animated' checked. Give it a name in case you want to refer to it in code.
in the listViewController's IBAction add this:
[[self presentingViewController] dismissViewControllerAnimated:YES completion:nil];
That should achieve your result. You can use the completion block to send information back from the list view to the map view, and/or set the map view as the listView's delegate.
If you are not using the storyboard check this apple guide
Presenting View Controllers from Other View Controllers
especially "Presenting a View Controller and Choosing a Transition Style".
There is one catch with this approach - when the presented view flips onto the screen, the entire previous view, including the tab bar, is flipped out of the way. The idea is that this is a modal view which the user is required to dismiss before doing anything else in the app.
(2) push/pop in a single navController If this does not suit your intent, you can navigate using a single NavigationController with push and popping of views, and you can hide the back button ... but you really would need to keep the back button functionality as you do want to go back to the mapView, not on to a new map view.
To hide the back button try:
self.navigationItem.hidesBackButton = YES
in the uppermost viewControllers' viewDidLoad
Then you can add a barButtonItem in the xib/storyboard, with this kind of IBAction:
[self popViewControllerAnimated:NO]
or
[self popToRootViewControllerAnimated:NO]
You would have to construct the flip animation in code as it is not supported as a built-in with UINavigationController (best left as an exercise for the reader!)
(3) swapping views in a single viewController As ghettopia has suggested, you could use a single viewController inside a navController (or with a manually place navBar) and swap two views around using the UIView class methods
transitionFromView:toView:duration:options:animations:completion
transitionWithView:duration:options:animations:completion.
This could be a good simplifying solution as your list and map are essentially two views of the same data model.

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