I'm hoping that i'm simply overlooking something simple. But here the scenario.
I have a root vc that opens a modal view LoginScreen. In that view class I've set up a protocol (ViewControllerDelegate) synthesized, and once a user logs in via the modal, the parent VC closes the modal and all is well.
In LoginScreen.m to close the modal all I have to use is this code:
[self.delegate loginConfirmed:self];
That works perfectly. However, I have another view that gets pushed is login is confirmed. Still as a modal of course. Call it LoginScreen2.
I can't figure out how to get the Modal to close from LoginScreen2 and get back tot he root VC. I've tried a bunch of different variations like this, but no luck.
[((LoginScreen *)self.parentViewController).delegate loginConfirmed:((LoginScreen *)self)];
I've been searching and messing around for a couple hours, with no luck. Again I'm hoping I'm just missing something simple and just not seeing it. If anyone has any ideas that would be awesome.
Not sure who is presenting the second view controller, but one thing that might help you is to know that a modally presented view controller can dismiss itself:
[self dismissModalViewControllerAnimated:YES];
The root view controller can check the user state when it appears, and presentModalViewController:Login1. Login1 changes the user sign-in state, and dismisses itself. Root sees different user state (when it's about to reappear via the viewWillAppear: method) and presents modal on Login2. No delegation needed.
Related
This is quite a common question, but after trying a lot to fix the issue, finally I have decided to post it on StackOverFlow.com
I have a tab bar based app. The tab bar is loaded in AppDelegate.m as follows:
self.tabBarController.viewControllers = #[viewController1, viewController2 , viewController3 , viewController4 , viewController5];
My 5th tab has a button for logout. When user clicks logout, I want to clear/reset entire app and go to login page which is a modalviewcontroller.
I have tried following while logging out:
NSMutableArray * vcs = [NSMutableArray
arrayWithArray:[self.tabBarController viewControllers]];
[vcs removeAllObjects ];//ObjectAtIndex:4];
[self.tabBarController setViewControllers:vcs];
This removes all views from tab-bar. But when I login again, nothing is displayed. I want to show my home screen, i.e. tab item 1 selected by default.
I have read that its not a good practice to call didFinishLaunchingWithOptions again manually.
Is there a way where I can reset all tab-bars and reinitialise them again ?
This will help me solving one more problem that is linked with this situation. When user logs out and log in again, and view controllers are not cleared, then logout page is shown again after login. And not the home view controller.
Please help.
Thanks in advance.
If you really want to start over, you should put a method, lets call it -(void)setupTabBarController, in the app delegate, and at start up you would call it from application:didFinishLaunchingWithOptions:. Later when you want to reset, call that method again from the login page. This method would have the creation of all the tab bar controller's view controllers in it, as well as setting the tab bar controller as the root view controller of the window.
However, it's not really clear that you need to do this, depending on what state all those controllers are in at logout time. Your problem with the logout page being shown again could probably be fixed in a simpler way.
Well, nothing is showing because you removed the views and never added them back in.
There is no need to remove the view controllers from the tab bar after you log out. You can just write a method to reset all the data in each view controller and then set the selected tab to what you desire.
I know, this is not really an answer to your question, but this could maybe help you too (and as I can't comment on post yet i have to post it like this :)).
I had some problems with "resetting" the navigation stack when the user logs out in my tabbar app too. In the beginning I had my tabbar-controller as the root controller and was displaying the login-screen modally but than it was quiet hard reset the navigation stack once the user loged out.
What I ended up doing and it works for me quiet well is, I set the login controller as root controller and after log in displayed the tab navigation modally. On log out I simply dismiss the tabbar-controller again - everything starts from the beginning again.
Maybe you could try this and see if it is easier to handle.
You should be add tabBar controller on second view controller. main view controller show home screen. when you navigate second view controller then you add tabBar here.
I am currently design a simple application which the user should login first.
I set the login page as the root view of the window. Once the user login the system, it will modal present a tabbar view.
I guess the login pages (which are actually several view controllers in navigation controller) are useless after then. Can I dealloc those pages and reset the root view as the tabbar controller?
Don't set the Login page as the root. Presenting a modal view with a tab bar that should now act as the root is the wrong way, and most likely be rejected by Apple for this.
The second view you currently have, or the view the user should see AFTER logging in should be the root. In this root view, check to see if the user is logged in, if not, present the login as the modal view.
You should never call dealloc directly from your code. With no ARC, the only exception is calling dealloc for the super class. With ARC (and you should use ARC), you don't have to call dealloc anymore.
That being said, since the login screen is only going to be needed in a few runs, why don't invert the flow, and make the tabbar controller the root of your app, and only when it is needed present the login view, perhaps without animation, so the user will never see the root?
New to iOS, kindly bare if the question is very basic? When I press the tab button multiple times, it is not invoking viewWillAppear function? If I am wrong, then which function gets invoked, each time a tab button is pressed being on the same tabview?
You are correct, viewWillAppear is a little special, it is usually called automatically but in some cases including when you are adding a view controllers view manually (view addSubview:), and also when adding this as a view controller to a UITabViewController it doesn't get messaged.
This however is only for the root view, as you navigate (maybe with a navigation controller) back and forth, that root view's viewWillAppear will get triggered as some point.
In short, if you need to implement something in viewWillAppear in these cases, you should message it yourself when you know it's going to be presented. You can handle this case in your view controller, check out the following article about the matter:
http://www.touchthatfruit.com/viewwillappear-and-viewdidappear-not-being-ca
Good luck.
In my previous question on UIView animations I mentioned that I have to simulate the modal behavior for some view. Here I'll explain why and ask about some better solution.
The first view a user should see in my app is the login screen. Upon successful authentication the program checks if the user is a parent or a child (in a family). For each of these roles the app must provide different functionality.
So I designed the app like this:
Declare outlets for the login view controller and a tab bar controller (for the main part of the interface) in my AppDelegate.
In the application:didFinishLaunchingWithOptions: method
Set the rootViewController of the main window to the login view controller.
Make AppDelegate the delegate for the login controller, so it can send notification when it's done its job.
When AppDelegate receives the message on successful login, it determines whether the user is a parent or a child, instantiates the set of view controllers that provide corresponding functionality and passes them to the tab bar controller.
At last AppDelegate switches the rootViewController of the main window to the tab bar controller.
Certainly the user can logout, then the rootViewController is switched back again to the login controller.
I would like to present and dismiss the login screen as if it is a modal view, but AppDelegate only has a bare window, thus I don't have an object to send presentModalViewController: to. This brings up a question:
First of all, is it a good design?
And if it is, how do I simulate a modal behavior correctly?
I think you're on the right track.
However, I always try to get out of the app delegate as soon as I can, leaving it only to do application-level things (like respond to notifications, go in and out of background). In this case, doing so will help you.
In the appDelegate, create a new UIViewController class, something like "startUpController".
Add it's view to the app window.
Then in your startUpController, do everything that you used to do in the app delegate (login, tab bar setup, etc.).
And now, since you're in a view controller, you can presentModalViewController to your hearts content.
Hii,
you should refer this
http://code.google.com/p/tweetero/
https://github.com/jbrien/WordPress-iPhone
Hope this helps!
I am writing an application(for iPhone) that uses the UINavigationController to show different view via pushViewController. I am trying to push multiple UIViewController immediately upon application startup without user interaction. When an user open up the application, they will be looking on a screen with a navigation bar on the top that already have a back button.
The problem I am experiencing is that viewWillDisappear and viewDidDisappear of a ViewController does not always get call if another ViewController is pushed on top of it immediately upon application start up without user interaction. If the ViewController being pushed on top is activate by the user with a button click, then viewWillDisappear and viewDidDisappear of the view being cover always get call.
Note. viewWillAppear and viewDidAppear of the covered view controller always get called.
In the code that is experiencing the problem, I am pushing the new view controller in viewDidAppear of the previous ViewController.
Anyone know what I might be doing wrong or if the behavior I am seeing is expected?
The problem I am experiencing is that viewWillDisappear and viewDidDisappear of a ViewController does not always get call if another ViewController is pushed on top of it immediately upon application start up without user interaction.
Sound pretty sensible to me. After all, the "covered" view never appeared on screen, so it cannot disappear. I would expect this behavior.