[self navigationController] pushViewController：

Question

我有一个带标签的应用，我会从表格列表中加载页面详细信息。

在我的appDelegate.m中，我有以下功能：

    @synthesize DetailController = _DetailController;
-(void)loadDetails{
    [[self navigationController]pushViewController:_DetailController animated:YES];
}

我从view firstviewController调用

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

 [[self appDelegate] setCurrentlySelectedBlogItem:[[[self rssParser]rssItems]objectAtIndex:indexPath.row]];
    [[self appDelegate] loadDetails];
}

但请勿更改视图。为什么呢？

在我的appDelegate.h

中

#import <UIKit/UIKit.h>

@class FirstViewController;
@class DetailViewController;
@class RSSEntry;

@interface AppDelegate : UIResponder <UIApplicationDelegate, UITabBarControllerDelegate>{
    UIWindow * _window;
    FirstViewController * _viewController;
    UINavigationController * _navigationController;
    DetailViewController * _DetailController;
    RSSEntry * _currentlySelectedBlogItem;
}

@property (strong, nonatomic) UIWindow *window;
@property (strong, nonatomic) UITabBarController *tabBarController;
@property (nonatomic, strong) IBOutlet FirstViewController *viewController;
@property (nonatomic, strong) IBOutlet UINavigationController * navigationController;
@property (nonatomic,strong) IBOutlet DetailViewController * DetailController;
@property (readwrite,strong) RSSEntry * currentlySelectedBlogItem;

-(void)loadDetails;

@end