objective-c - iOS：处理 didSelectViewController 时的警告

Question

以下代码：

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

产生以下警告：

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

什么是正确的方法来viewController转换到正确的类MySearchViewController来调用它的方法？

Answer 1

只需更改为：

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