iphone - 单击 NavigationView 中嵌入的弹出框后如何查看最新的子视图？

Question

单击按钮时，会出现嵌入在 NavigationView 中的 popoverView。我的代码如下：

  -(IBAction)myStuffPOP:(id)sender
   {
    if(myStuffListViewController ==nil)
    {        
        myStuffListViewController = [[MyStuffListViewController alloc] init]; 
    }
    UINavigationController *navcontroller=[[[UINavigationController alloc] initWithRootViewController:myStuffListViewController] autorelease];
 // Here we create popover controller.
    mystuffPopoverView =  [[UIPopoverController alloc] initWithContentViewController:navcontroller] ;
    CGRect popoverRect = [self.view convertRect:[sender frame] fromView:[sender superview]];

    popoverRect.size.width = MIN(popoverRect.size.width, 100);
    popoverRect.size.height = 40;

    [mystuffPopoverView presentPopoverFromRect:popoverRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];

    [navcontroller setNavigationBarHidden:NO];

} 

在 PopoverView 的 NavigationView 中：

1st subView ---> 2nd SubView ---> 3rd Subview

如果我触摸3rd SubView， PopoverView 就会消失。

我的问题是：

当我再次单击按钮时，我想查看最新的视图 -3rd SubView not 1st SubView.

Answer 1

无需UINavigationController每次都创建。保存方式与MyStuffListViewController

if ( myNavigationController == nil )
    myNavigationController = [[[UINavigationController alloc]     initWithRootViewController:myStuffListViewController] autorelease];

Answer 2

1. UINavigationController *navcontroller;在 .h 文件中声明

2. navcontroller例如，在 viewDidLoad 方法中，仅使用您的根视图控制器创建一次。

   - (void)viewDidLoad {     
       myStuffListViewController = [[MyStuffListViewController alloc] init]; 
       navcontroller=[[UINavigationController alloc] initWithRootViewController:myStuffListViewController]; }
   

3. 显示具有现有导航堆栈的 UIPopoverController

   -(IBAction)myStuffPOP:(id)sender    {
       //Here we create popover controller.
       mystuffPopoverView =  [[UIPopoverController alloc] initWithContentViewController:navcontroller] ;
       CGRect popoverRect = [self.view convertRect:[sender frame] fromView:[sender superview]];
   
       popoverRect.size.width = MIN(popoverRect.size.width, 100);
       popoverRect.size.height = 40;
   
       [mystuffPopoverView presentPopoverFromRect:popoverRect inView:self.view permittedArrowDirections:UIPopoverArrowDirectionUp
   animated:YES];
       [navcontroller setNavigationBarHidden:NO]; }
   

4. 不要忘记release对象

   - (void)dealloc {   
       [myStuffListViewController release];
       [navcontroller release];
   }