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iOS Build a Self-Destructing Message iPhone App Designing and Starting the App A Storyboard with a Tab Bar Controller

Posted by hunche
hunche
3,339 Points

Challenge task 1 of 3 We just saw how to change tabs by tapping on them, but we can also do this programmatically using

We just saw how to change tabs by tapping on them, but we can also do this programmatically using the selectedIndex property of UITabBarController. The tab bar controller in the example below has three tabs. Use dot-notation or the setSelectedIndex: method to set the 3rd tab as the selected tab. Note: The tabs are indexed just like arrays, meaning the 1st tab is at index 0.

import "MainViewController.h"

import "UITabBarItem.h"

@implementation MainViewController

  • (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'. //my answer is below ?????? But , these 2 lines are wrong,I don't know ?????????

    self.tabBarController.selectedIndex = 2; self.view = tabBarController.view;
    } @end

1 Answer

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

remove the line that sets the view. you dont need that

#import "MainViewController.h"
#import "UITabBarItem.h"

@implementation MainViewController

- (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.selectedIndex = 2;

}

@end