的iOS：警告處理didSelectViewController

Question

下面的代碼時：

- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController { 
    if (viewController == [tabBarController.viewControllers objectAtIndex:0]) { 
     MySearchViewController *controller = viewController; 
     [[controller tableView] reloadData]; 
    } 
} 

產生以下警告：

Incompatible pointer types initializing 'MySearchViewController *__strong' with an expression of type 'UIViewController *__strong' 

什麼是投viewController到合適的類MySearchViewController調用它的方法的正確方法？

Answer 1

就改成這樣：

- (void)tabBarController:(UITabBarController *)tabBarController didSelectViewController:(UIViewController *)viewController { 
    if (viewController == [tabBarController.viewControllers objectAtIndex:0] && [viewController isKindOfClass:[MySearchViewController class]]) { 
     MySearchViewController *controller = (MySearchViewController *)viewController; 
     [[controller tableView] reloadData]; 
    } 
}