在纵向模式下按下新视图控制器后，iOS UISplitViewController的Popover控制器按钮消失

在我的UISplitViewController应用程序中，我有

In my UISplitViewController application, I have

• RootViewController - 左窗格中的视图控制器。


• DetailViewController - 在右侧窗格中查看控制器。

当一个项目（在点击RootViewController中的UITableView，将设置新的视图控制器，如下所示：

When one item (which is in a UITableView) in RootViewController is tapped, new view controller will be set as the following shows:

[detailViewController setViewControllers：[NSArray arrayWithObjects：newViewController，nil] animated：animated];

/ / detailPane是我的DetailViewController

所有在横向模式下工作得很好。但是，我无法使UISplitViewController在我的肖像模式下工作，也就是说，当我在portait模式下启动并使用应用程序时，RootViewController的弹出按钮在我的DetailViewController中没有正确显示。

All works pretty well in landscape mode. However, I can't make the UISplitViewController work as what I want in portrait mode, that is, the RootViewController's popover button does not appear appropriately in my DetailViewController when I launch and use the application in portait mode.

当我以纵向模式启动应用程序时，弹出按钮会正确显示。但是在弹出窗口中的一个项目并且在detailViewController上设置了新的视图控制器后，该按钮消失了。我必须将设备旋转到横向，然后再次回到纵向再次使按钮出现。

When I launch the app in portrait mode, the popover button appears appropriately. But after tapping one item in the popover and a new view controller has been set on detailViewController, the button disappeared. I have to rotate the device to landscape and then back to portrait again to make the button appear again.

我在我的应用程序的AppDelegate中设置了我的UISplitViewController的委托，如下所示：

I set my UISplitViewController's delegate in my application's AppDelegate as follows:

self.splitViewController.delegate = self.detailViewController

这是我的UISplitViewControllerDelegate实现

And here is my UISplitViewControllerDelegate implementation

- (void)splitViewController: (UISplitViewController*)svc willHideViewController:(UIViewController *)aViewController withBarButtonItem:(UIBarButtonItem*)barButtonItem  forPopoverController: (UIPopoverController*)pc {
    NSLog(@"Will hide view controller");
    barButtonItem.title = @"Menu";
    [self.navigationItem setLeftBarButtonItem:barButtonItem];
    self.popoverController = pc;
}

- (void)splitViewController: (UISplitViewController*)svc willShowViewController:(UIViewController *)aViewController invalidatingBarButtonItem:(UIBarButtonItem *)barButtonItem {
    NSLog(@"Will show view controller")
    NSMutableArray *items = [self.navigationItem.leftBarButtonItems mutableCopy];
    [items removeAllObjects];
    [self.navigationItem setLeftBarButtonItems:items animated:YES];
    [items release];
    self.popoverController = nil;   
}

非常感谢任何提示或帮助。
谢谢。

Any hint or help is greatly appreciated. Thanks.