从appdelegate中的viewcontroller调用方法不会更改屏幕上的文本

Question

Every time when I launch the app, I want to change the text on the screen. The method is called but text does not change.

myAppDelegate.m

- (void)applicationDidBecomeActive:(UIApplication *)application
{

    [[UIApplication sharedApplication] setApplicationIconBadgeNumber:-1];
    viewController *object = [[viewController alloc] init];
    [object methodA];
}

viewController.m

-(void)methodA{
    //Create an URL pointing to your plist
    NSURL *plistURL = [[NSBundle mainBundle] URLForResource: @"myPlist" withExtension: @"plist"];
    //Read the plist from the application bundle into an array object.
    NSArray *stringsArray = [NSArray arrayWithContentsOfURL: plistURL];
    //Create a random index into the array
    NSUInteger randomIndex = arc4random_uniform(stringsArray.count);
    //Fetch the string at that random index
    NSString *randomString = stringsArray[randomIndex];
    //Set some label's text to the random string.
    _myLabel.text = randomString;
    NSLog(@"methodA");

}

I get "methodA" in my log.

Answer 1

Try this code:

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"MainStoryboard" bundle: nil];
yourViewController *object = [storyboard instantiateViewControllerWithIdentifier:@"id"];
[object methodA];

Replace MainStoryboard with your storyboard name and id with your view controller id. You can set the id in your storyboard. Last replace yourViewController with your view controller.(Do not forget to import it).