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iOS

Posted by Dan Boyle
Dan Boyle
2,978 Points

Second Code Challenge In Ribbit Project

I am having some issues completing this code challenge. (This is going to be a long project... in a good way though!)

Here's the part I can't seem to figure out.

**** Directions of challenge **** The tabs are stored in an array named tabBarItems (line 9). Declare a UITabBarItem variable named tab and set it from tabBarItems. Use the selectedIndex we just set as the index for the tab you get from the tabBarItems array. **** Directions of challenge end ****

**** My code so far ****

  • (void)viewDidLoad { [super viewDidLoad];

    NSArray *tabBarItems = self.tabBarController.tabBar.items;

    // Add your code below! The property for MainViewController's // tab bar controller is named 'tabBarController'.

    [self.tabBarController setSelectedIndex:2];

    UITabBarItem *tab = [[UITabBarItem alloc] initWithTabBarSystemItem:???];

}

**** My code so far end ****

I read about UITabBarItem and it seems it needs to be allocated and initiallized with initWithTabBarSystemItem in this case?

I feel that I am also making this harder than it needs to be.

Here's what the knowledge base gave me...

  • (id)initWithTabBarSystemItem:(UITabBarSystemItem)systemItem tag:(NSInteger)tag

But I don't really understand that... even when I keep reading more.

2 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

you dont need to allocate and init it. just set it using the tabBarItems array and the selected index as the index of the array

NSArray *tabBarItems = self.tabBarController.tabBar.items;

// Add your code below! The property for MainViewController's // tab bar controller is named 'tabBarController'.

[self.tabBarController setSelectedIndex:2];

UITabBarItem *tab = [tabBarItems objectAtIndex:self.tabBarController.selectedIndex];
Dan Boyle
Dan Boyle
2,978 Points

Thanks Stone!

Why don't you have to allocate and initialize UITabBarItem?

Dan Boyle
Dan Boyle
2,978 Points
Dan Boyle
Dan Boyle
2,978 Points

Thanks Stone!

Why don't you have to allocate and initialize UITabBarItem?

Stone Preston
Stone Preston
42,016 Points

because the tab bar item already exists in memory (you dont need to create a new one). you are just creating another variable to point to it so you can reference it.