Jumping directly to a View controller that is usually accessed through one of the tabs in a TabBarViewController

Question

This is the hierarchy of my app

1. There is a TabBarViewCOnyroller with 4 tabs
2. Each tab shows a TableListViewOCnroller
3. When user selects a row in the the TableListViewCOntrilelrs, different view controllers are pushed depending on which tab and which row. Each of these has a navigate back button to that will take the UI back to Tab-Bar view controller

For e.g. Chat tab displays a list of chats in timestamp sorted order. The last chat in the exchange with each far-end is shown. When user selects a certain row, it goes it into a view controller that shows all the messages between user and far-end who is connected with the row.

When I get a push notification with a message from a particular far-end, and user selects it, I want the app to directly shift to the view controller with all the messages with the far-end with a navigate back button pointing to the "Chat tab". I know how to show the message display view controller programmatically, but I don't know how to embed it in a way that will allow user to navigate back to the chat tab.

Can someone point me to some example code on how this can be achieved. Sorry to be asking for a ready-made solution. Too much base-framework stuff to master, so no time to master UI stuff!

EDIT with code I am using

    NSInteger index = 1 ;// the index of the chat tab
    UITabBarController *myTabBarController = (UITabBarController *)self.window.rootViewController;
    myTabBarController.selectedIndex = index;
    UINavigationController *navVC = myTabBarController.viewControllers[index];

    ChatListTableViewController *listVC = [[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"chatlistview"];
    listVC.navigationItem.backBarButtonItem.title = @"Chats";

    MessageDisplayViewController *detailVC = [[MessageDisplayViewController alloc] init];
    //Initialize all the variables needed by JSQMessage class
    detailVC.hidesBottomBarWhenPushed = YES;
    detailVC.title = detailVC.recipient = userInfo[@"sender"];
    //To Do Map farEndID to farEndNickName using unique user table
    detailVC.recipientNickName= detailVC.recipient ;
    detailVC.managedObjectContext=self.managedObjectContext ;
    detailVC.senderDisplayName=[[NSUserDefaults standardUserDefaults] stringForKey:@"NickName"];
    detailVC.senderId=[[NSUserDefaults standardUserDefaults] stringForKey:@"UserID"];

    //navVC.viewControllers = @[listVC, detailVC];
    navVC.viewControllers = @[listVC];
    [navVC pushViewController: detailVC animated:NO];

Answer 1

To change the tab bar controller to a tab, use

NSInteger index = // the index of the chat tab
myTabBarController.selectedIndex = index;

The UINavigationController at that tab can be manipulated programmatically as well.

1. Get the navigation controller at the tab:

   UINavigationController *navVC = myTabBarController.viewControllers[index];
   

2. Build the root view controller that shows all the conversations as you normally do.

   UIViewController *listVC = // you build this somehow in your code already... do that
   listVC.title = @"Chat";
   

3. Build the view controller that shows a conversation detail as you normally do, initializing it with the newly received message.

   UIViewController *detailVC = // you build this somehow in your code already... do that
   

4. Replace the navigation view controller stack.

   navVC.viewControllers = @[listVC];
   [navVC pushViewController: detailVC animated:NO];