ios - '-[UINavigationController setLanguage :]: unrecognized selector sent to instance 0x7f8fba7df4e0'

Question

几个小时前，这段代码没有给我带来任何问题，但是，在更新我的 XCode 之后我的 XCode 并删除了第 3 方框架，它突然给了我上述异常。我非常困惑，因为我认为从那时到现在除了更新我的 XCode 之外没有任何变化可能导致问题。任何人都可以看到问题吗？

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

/*We check to make sure the segue corresponds to segue we created when a cell is selected*/
if ([[segue identifier] isEqualToString:@"show"]) {

   /*Get a pointer to the selected row*/
    NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];

    /*Get a pointer to the ViewController we will segue to*/
    ViewController *viewController = segue.destinationViewController;

    /*Pass the dialect and code back to the ViewController*/
   viewController.language = self.languages.allKeys[indexPath.row];
    viewController.code = [self.languages objectForKey:viewController.language];

  }
}

具体来说，以下两行导致了异常:

viewController.language = self.languages.allKeys[indexPath.row];
viewController.code = [self.languages objectForKey:viewController.language];

Answer 1

您的 segue 的目标 Controller 是 UINavigationController，您的 View Controller 可能是该导航 Controller 的顶层 View Controller 。你可能想要:

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {

    /*We check to make sure the segue corresponds to segue we created when a cell is selected*/
    if ([[segue identifier] isEqualToString:@"show"]) {

    /*Get a pointer to the selected row*/
    NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];

    UINavigationController *navController = segue.destinationViewController

    /*Get a pointer to the ViewController we will segue to*/
    ViewController *viewController = navController.topViewController;

    /*Pass the dialect and code back to the ViewController*/
    viewController.language = self.languages.allKeys[indexPath.row];
    viewController.code = [self.languages objectForKey:viewController.language];
  }
}