如何在UINavigationController的RootViewController上显示后退按钮？

Question

这是我的代码.我想在开放的rootviewController上放一个后退按钮.

- (void)selectSurah:(id)sender {

    SurahTableViewController * surahTableViewController = [[SurahTableViewController alloc] initWithNibName:@"SurahTableViewController" bundle:nil];
    surahTableViewController.navigationItem.title=@"Surah";

    surahTableViewController.navigationItem.backBarButtonItem.title=@"Back";

    UINavigationController *aNavigationController = [[UINavigationController alloc] initWithRootViewController:surahTableViewController];

    [self presentModalViewController:aNavigationController animated:YES];   
}

Answer 1

我不相信可以将根视图控制器从导航堆栈中弹出,但您可以将其UIButton添加为自定义视图UIBarButtonItem:

UIButton *b = [[UIButton alloc]initWithButtonType:UIButtonTypeCustom];
[b setImage:[UIImage imageNamed:@"BackImage.png"] forState:UIControlStateNormal];
[b addTarget:self action:@selector(back:) forControlEvents:UIControlEventTouchUpInside];
self.leftBarButtonItem = [[UIBarButtonItem alloc]initWithCustomView:b];

可以在此处找到适合的iOS UI元素的PSD .

Answer 2

Faizan,

Helium3评论很有​​意义.

我想你的按钮需要以模态方式解除控制器,这是真的吗？如果我错了,请纠正.

如果是这样,你可以创建一个新的,UIBarButtonItem并设置为左(或右)按钮UINavigationController navigationItem.要不破坏封装,请在控制器的viewDidLoad方法中创建它SurahTableViewController.

- (void)viewDidLoad
{
    [super viewDidLoad];

    // make attention to memory leak if you don't use ARC!!!
    self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Close"
           style:UIBarButtonItemStyleBordered
             target:self
             action:@selector(close:)];
}

-(void)close:(id)sender
{
    // to dismiss use dismissViewControllerAnimated:(BOOL)flag completion:(void (^)(void))completion
    // dismissModalViewControllerAnimated: is deprecated

    [self dismissViewControllerAnimated:YES completion:^{ NSLog(@"controller dismissed"); }];
}