Keep state of navigation controller and only change view - ios

I have an application with a drop down menu as the titleView of my NavigationController. When a user selects an item of the drop down menu, the entire view should switch contents, however, the NavigationBar should remain the same. The NavigationBar should not have to reload any data and the titleView should remain a drop down menu.
The original view upon opening the app:
The view upon touching the dropdown menu:
I currently see a few ways of going about this:
Set up a UIViewController for each option, perform the segue, and reload the data.
Why this is bad: I will have to set up a segue identifier for each ViewController, meaning if I have 15 options in my drop down menu, I will have 210 segue identifiers laying around. I will also have to reload all of my NavigationBar data.
Why this is good: I will have a clear area to set up each individual view.
Programmatically add and remove UIButtons, UILabels, and UIWhatevers as I need them.
Why this is bad: This will create a lot of code inside just one ViewController and things could get difficult to debug.
Why this is good: The NavigationBar never gets reloaded.
Add a container and embed a unique ViewController for each item as I need it.
Why this is bad: All of my work would still be in the main ViewController and I'd have to manage the logic of the embedded ViewController inside one Controller.
Why this is good: The NavigationBar never gets reloaded.
A completely different method suggested by someone else because I don't know the most efficient way of doing this.
So, in conclusion, what is the most efficient way to maintain state of my NavigationBar when switching my main content in my View?

Option 3 is the best out of the three you listed. Options 1 and 2 will get more and more complicated the more view controllers you want to add. Compare that to UINavigationController, UITabBarController, or UIPageViewController which do not need to be more complicated in order to handle 10 screens vs. 100 screens.
I would suggest creating a custom container view controller (Apple's Reference)
I see 2 immediate approaches to implementing this:
Subclassing UIViewController - this is how Apple's container view controllers are implemented
Subclass UITabBarController - I have done this successfully, subclassing UITabBarController to show a custom tab bar at the top instead of along the bottom.

Related

Xcode 6 - Swift - Custom Tabbar with Navigation

I'm trying to create a tabbed application with navigation elements inside the tab bar, as seen in the picture below (the red bar) using Swift/XCode 6.2. Basically those three icons in the middle will direct the user to different view controllers. The other two icons would be context-based. For example, on a table view page you would see the menu icon and add new icon as seen in the image. However, clicking on a row would change the menu icon to a back icon, and the add icon to something else.
That's the general idea, but I'm having a very hard time implementing something even close to this. The first issue is that whenever I embed a view in a Tab Bar Controller, I can't move the tab bar to the top. However, when I create a custom UITabView in a View Controller, Control + Click and dragging a Tab Bar Item to another view doesn't create a segue. I haven't even begun to tackle having the navigation elements inside the bar.
I guess what I'm asking is just for a little guidance on what route to take to tackle this. I'm assuming I can't use a Tab Bar Controller or Navigation Controller because it doesn't seem like I can customize them all that much. So custom Tab Bar and Navigation Bars, and then implemnt the segues and button changes programmatically?
Thanks.
I will try to guide you from an architectural perspective (so you won't find much code below).
Using a UITabBarController
In order to achieve what you are suggesting, you are right you cannot use a UITabBarController straight away, among several reasons, the most immediate one is that they are meant to be always at the bottom and you want it in top (check Apple's docs). The good news is that probably you don't need it!
Note: If you still want to go with a UITabBarController for whatever reason, please see #Matt's answer.
Using a UINavigationController
You can use a UINavigationController to solve this task, since the UINavigationBar of a UINavigationController can be customized. There are multiple ways on how you can organize your view's hierarchy to achieve what you propose, but let me elaborate one option:
To customize a UINavigationBar's to add buttons, you just need to set its navigationItem's title view:
// Assuming viewWithTopButtons is a view containing the 3 top buttons
self.navigationItem.titleView = viewWithTopButtons
To add the burger menu functionality on a UINavigationController you can find several posts on how to do it and infinite frameworks you can use. Check this other SO Question for a more detailed answer (e.g. MMDrawerController, ECSlidingViewController to mention a couple).
About organizing your view hierarchy, it really depends on if when the user taps one of the main top buttons, it will always go to the first view controller in the new section or if you want to bring him back to the last view in the section where he was.
3.1 Switching sections displays the first view of the new section
Your app's UIWindow will have a single UINavigationController on top of the hierarchy. Then each of the 3 top buttons, when tapped, will change the root view controller of the UINavigationController.
Then, when the user changes section, the current navigation hierarchy is discarded by setting the new section view controller as the UINavigationController root view controller.
self.navigationController = [sectionFirstViewController]
3.2 Switching sections displays the last displayed view in the new section
This will require a slightly modified version of the above, where your each of your sections will have its own UINavigationController, so you can always keep a navigation hierarchy per section.
Then, when the user taps one of the top buttons to switch section, instead of changing as previously described, you will change the UIWindowroot view controller to the new section's UINavigationController.
window.rootViewController = sectionNavigationController
Using a custom implementation
Of course, the last and also very valid option would be that you implement yourself your own component to achieve your requirements. This is probably the option requiring the biggest effort in exchange of the highest customizability.
Choosing this option is definitely not recommend to less experienced developers.
I'd like to take a stab at this--I think it is possible to use a tab bar controller here.
Your topmost-level view controller will be a UITabBarController with a hidden UITabBar.
Each tab is contained in a UINavigationController.
All view controllers in the navigation controller will be a subclass of a view controller (say, SwitchableViewController).
In SwitchableViewController's viewDidLoad, you set the navigation item's title view (i.e. whatever's at the center; self.navigationItem.titleView) to be the view that holds the three center buttons. Could be a UISegmentedControl, or a custom view.
Whenever you tap on any of the buttons, you change the topmost UITabBarController's selected index to the view controller you want to show.
Issues you may encounter:
Table views inside tabs will have a scrollIndicatorOffset at the bottom even if the tab bar is hidden.
Solution: Play around with the automaticallyAdjustsScrollViewInsets of the tab bar controller, or the inner view controller. https://stackoverflow.com/a/29264073/855680
Your title view will be animated every time you push a new view controller in the navigation stack.
Solution: Take a look at creating a custom transition animation for the UINavigationController.

Designing view on top of multiple embed views

I have the task to design a application that has a main view which is always visible (it has a button on it's bottom side, and when pressed a image displays on top of all views), and a set of TableControllerView's that should appear under it, and the user needs to be able to navigate through them.
I know that you can embed a view inside another, but you cannot refer more than one view to it. The current way I'm trying to do now load one TableViewController inside the embed view, and when the user clicks the cell I manually load the other controller and add it as a child of the main view, which is the RootViewController. The problem with this approach is that the navigation bar gets stuck using the root view controller, so I have to manipulate the main navigation items on each subview transition, and second is that the frame for the second view I load is coming as it had full size, making some cells be under the main view button. This way doesn't uses segues for transition, so it makes the storyboard kinda useless.
I was thinking into using a TabViewController with it's tab hidden, but wanted to ask here for a better solution.
As you discovered, a TableViewController likes to fill up the whole screen (except navigation bars, tab bars, status bar, etc. which are official Cocoa Touch GUIs). When you want a table view to fill only part of the screen, you are supposed to use a UITableView but not a UITableViewController. You set your custom view controller object (subclass of UIViewController, not UITableViewController) as the table view delegate and data source. You will need to duplicate part of the functionality of UITableViewController in your custom view controller, but it's not a lot more than you have to do already to supply the data.
You should probably follow the standard design pattern and have separate view controller objects for each of the "pages" the user can navigate to. You just have a main button and image on each of them. But I could imagine why that might not give you exactly the effect you want.

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.

Tab bar items are the same except for their data set in storyboard

I've set up a storyboard with a UITabBarController object and I'd like to add two tabs to that, but both tabs are going to be exactly the same except for the data they will display. Obviously, I could drag in two new view controllers and connect them up and just maintain the views separately, but I don't want to do this at all.
Does anyone know the most efficient way of doing this?
I've done this by using a regular UIViewController with a tab bar at the bottom, rather than using a UITabBarController. You just have to use the UITabBar delegate method, tabBar:didSelectItem:, to detect the tab clicks, and then do whatever you need to do to switch what data is displayed in the single view.

How can I make one Tab Bar button refer to two views/controllers in iOS

I'm developing an iOS app just now with a Tab Bar navigation.
I have two screens which show the same information but in different formats (say, list and grid).
The two screens are different enough that they require separate controllers.
Users can toggle between the two views from a shared control bar button (toggle) at the top.
Scenario:
User presses the 'Places' button for the first time and it shows the places as a list.
They press 'grid' to see the same places displayed as a grid.
The user presses another tab bar button to navigate to a different screen.
When they press the "Places" button again, the app remembers their last viewed screen for places was the grid so the grid view is shown.
The user may then toggle back to list view. etc...
Can anybody recommend the best approach to achieving this?
One approach is to use one view controller that manages both views. That way, you don't have to bother with synchronizing data or subverting the normal function of UITabBarController -- there's just one controller. Also, don't try to overload the meaning of the tab for that controller. Instead, add a button to both views that tells the controller to switch to the other view. That'll be easier for your to build, and (more importantly) easier for the user to understand. It's not nice to make familiar controls do unfamiliar tricks.
If your view controllers are such that combining them into one would be complicated, then you can use two controllers and simply swap them in and out of the tab bar by modifying the tab bar controller's viewControllers array. You can still avoid having to sync data between them by having both controllers refer to the same data model.
I was trying to achieve this same thing, and it can actually be done with a basic setup of a TabBarController, NavigationControllers, ViewControllers, push segues, and unwinds.
TabBarController
|==> NavigationController --> PlacesController(grid view) --(push segue from nav bar)--> PlacesController(list view)
|==> NavigationController --> OtherController
|...
Make sure to have an unwind segue back from the list view controller to the grid view controller.
If you toggle between views then go to another tab (e.g. otherController) and come back, you'll return to the last view you were seeing because that's what is at the top of the stack of the NavigationController.

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