ios - 我如何观察 UIPopoverController 何时被解除？

Question

UISplitViewController 有委托(delegate)方法:

-(void)splitViewController:(UISplitViewController *)svc popoverController:(UIPopoverController *)pc willPresentViewController:(UIViewController *)aViewController

我希望从类似但不存在的委托(delegate)方法中获取功能:

-(void)splitViewController:(UISplitViewController *)svc popoverController:(UIPopoverController *)pc willDismissViewController:(UIViewController *)aViewController

关于考虑 UISplitViewController/UIPopoverController/UIKit 的最佳方式的想法通常不符合 KVO，所以我可以'将观察者添加到 UIPopoverController 的 isPopoverVisible 属性。

谢谢

回答:

//Sent when switching to portrait
- (void)splitViewController:(UISplitViewController*)svc willHideViewController:(UIViewController *)aViewController withBarButtonItem:(UIBarButtonItem*)barButtonItem forPopoverController:(UIPopoverController*)pc
{  
    ...

    self.popoverController = pc;
    [self.popoverController setDelegate:self];
}

-(void)splitViewController:(UISplitViewController *)svc popoverController:(UIPopoverController *)pc willPresentViewController:(UIViewController *)aViewController
{
    NSLog(@"SHOWING POPOVER");
}

- (void)popoverControllerDidDismissPopover:(UIPopoverController *)popoverController
{
    NSLog(@"HIDING POPOVER");
}

Answer 1

想通了，除了 UISplitViewControllerDelegate 之外，还添加 UIPopoverController 委托(delegate):

//Sent when switching to portrait
- (void)splitViewController:(UISplitViewController*)svc willHideViewController:(UIViewController *)aViewController withBarButtonItem:(UIBarButtonItem*)barButtonItem forPopoverController:(UIPopoverController*)pc
{  
    ...

    self.popoverController = pc;
    [self.popoverController setDelegate:self];
}

-(void)splitViewController:(UISplitViewController *)svc popoverController:(UIPopoverController *)pc willPresentViewController:(UIViewController *)aViewController
{
    NSLog(@"SHOWING POPOVER");
}

- (void)popoverControllerDidDismissPopover:(UIPopoverController *)popoverController
{
    NSLog(@"HIDING POPOVER");
}