Akshay Goel Akshay Goel - 1 year ago 84
iOS Question

Add a Tab Bar Controller Programmatically to current App Flow

I want to add a tab Bar Controller to my current App Flow. Currently I have a page with a button which on clicking opens a new viewcontroller with a web view where the user logs in and after login I want to take him to his home Page where the navigation bar has his name and a logout button in the right. The home page should also have a tab bar with 3 different tabs.
I am able to load the home page view from the webview and get the navigation bar. But I am unable to add the tabBar and get it working. I am confused as to where to add the code for adding TabBar. I am using the below code to add tab bar -

UITabBarController *tabBar = [[UITabBarController alloc] init];

HomeViewController *home = [[PPHomeViewController alloc] initWithUserName:[self.userInfo objectForKey:@"name"] Email:[self.userInfo objectForKey:@"email"] Phone:[self.userInfo objectForKey:@"phone_number"]];
home.tabBarItem = [[UITabBarItem alloc]initWithTabBarSystemItem:UITabBarSystemItemFavorites tag:1];
UINavigationController *homeNavController = [[UINavigationController alloc]initWithRootViewController:home];

RequestViewController *req = [[RequestMoneyViewController alloc]init];
req.tabBarItem = [[UITabBarItem alloc]initWithTabBarSystemItem:UITabBarSystemItemFavorites tag:2];
UINavigationController *reqNavController = [[UINavigationController alloc]initWithRootViewController:req];

UIViewController *thirdViewController = [[UIViewController alloc]init];
thirdViewController.tabBarItem = [[UITabBarItem alloc]initWithTabBarSystemItem:UITabBarSystemItemFavorites tag:3];
UINavigationController *thirdNavController = [[UINavigationController alloc]initWithRootViewController:thirdViewController];

UIViewController *fourthViewController = [[UIViewController alloc]init];
thirdViewController.tabBarItem = [[UITabBarItem alloc]initWithTabBarSystemItem:UITabBarSystemItemFavorites tag:3];
UINavigationController *fourthNavController = [[UINavigationController alloc]initWithRootViewController:fourthViewController];

tabBar.viewControllers = [[NSArray alloc] initWithObjects:homeNavController, reqNavController, thirdNavController, fourthNavController, nil];

UIImageView *homeImg=[[UIImageView alloc]initWithFrame:CGRectMake(0, 432, 80, 49)];
homeImg.image=[UIImage imageNamed:@"footer"];

UIImageView *reqImg=[[UIImageView alloc]initWithFrame:CGRectMake(81, 432,80, 49)];
reqImg.image=[UIImage imageNamed:@"footer"];

UIImageView *sendImg=[[UIImageView alloc]initWithFrame:CGRectMake(162, 432,80, 49)];
sendImg.image=[UIImage imageNamed:@"footer"];

UIImageView *localImg=[[UIImageView alloc]initWithFrame:CGRectMake(243, 432, 80, 49)];
localImg.image=[UIImage imageNamed:@"footer"];

[tabBar.view addSubview:homeImg];
[tabBar.view addSubview:reqImg];
[tabBar.view addSubview:sendImg];
[tabBar.view addSubview:localImg];

[[[UIApplication sharedApplication]keyWindow]addSubview:tabBar.view];

Currently I have put the above code in the viewDidLoad of a ViewController TabViewController which extends UITabBarController. In my webView controller I have put the following code -

TabViewController *tab=[[TabViewController alloc] init];
[self presentViewController:tab animated:YES completion:nil];

But the app crashes as soon as I click any tab other than the one already open.
Please Help.

Answer Source

The way I've done this in the past is to create a UITabBarController subclass that contains all of the tabBar creation code you have above.

Then use your UINavigationController to push the tabBar subclass to the screen.

Here's a sample of my UITabBarController subclass:

- (void)viewDidLoad {
    [super viewDidLoad];

    UIViewController *view1 = [[UIViewController alloc] init];
    UIViewController *view2 = [[UIViewController alloc] init];
    UIViewController *view3 = [[UIViewController alloc] init];

    NSMutableArray *tabViewControllers = [[NSMutableArray alloc] init];
    [tabViewControllers addObject:view1];
    [tabViewControllers addObject:view2];
    [tabViewControllers addObject:view3];

    [self setViewControllers:tabViewControllers];
    //can't set this until after its added to the tab bar
    view1.tabBarItem = 
      [[UITabBarItem alloc] initWithTitle:@"view1" 
                                    image:[UIImage imageNamed:@"view1"] 
    view2.tabBarItem = 
      [[UITabBarItem alloc] initWithTitle:@"view2" 
                                    image:[UIImage imageNamed:@"view3"] 
    view3.tabBarItem = 
      [[UITabBarItem alloc] initWithTitle:@"view3" 
                                    image:[UIImage imageNamed:@"view3"]