How to set tabBarItem's badge from AppDelegate.m (tabBarView is not root View) [duplicate]

问题

I can change badge value in AppDelegate.m by following code:

UITabBarController *tabController = (UITabBarController *)self.window.rootViewController;
[[tabController.viewControllers objectAtIndex:0] tabBarItem].badgeValue = @"Badge";

Only if the tabBarViewController is window's root view controller.

However, in my new program, tabBarController is not root view.

I have tried following code:

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle:nil];
UITabBarController *tabController = (UITabBarController *)[storyboard instantiateViewControllerWithIdentifier:@"tabBarController"] ;
[[tabController.viewControllers objectAtIndex:0] tabBarItem].badgeValue = @"Badge";

It just won't work. tabBarItem doesn't show any badge.

EDIT-

I have added following code to check does tabController created or not, The answer is YES.

if (tabController) {
     NSLog(@"tabController has been created ");
}else {
     NSLog(@"You have a null reference - The Object hasn't been created yet");
}

The answer is YES.

2013-03-01 11:57:00.600 Reporting[14854:907] tabControllerhas been created

But, the expected badge still does not show up.

回答1:

can you try this code Mr. Robert

       [[[[[self tabBarController] tabBar] items] objectAtIndex:0] setBadgeValue:[NSString stringWithFormat:@"%d", notificationCount ]];

来源：https://stackoverflow.com/questions/15129260/how-to-set-tabbaritems-badge-from-appdelegate-m-tabbarview-is-not-root-view

标签

ios

uitabbarcontroller

storyboard