如果存在多个视图控制器,如何关闭模式视图控制器
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【中文标题】如果存在多个视图控制器,如何关闭模式视图控制器【英文标题】:How to dismiss modal view controller if there are multiple view controller are presented 【发布时间】:2016-04-24 14:16:25 【问题描述】:我有一个视图控制器 A,它具有表视图并基于行选择,我将以模态方式打开另一个视图控制器 B。我还为我的应用程序实现了不活动计时器。现在,当 B 出现并且 A 正在呈现控制器并且由于用户不活动时,另一个视图控制器不活动视图控制器 C 将以模态方式在 B 之上打开。这意味着我有 A ,然后 B 在 A 之上,C 在之上B. 现在,用户从 C 中单击了一个按钮进行注销,我只能关闭 C。但视图控制器 B 永远不会被关闭。
不活动是使用触摸事件和通知实现的,通知在当前视图之上以模态方式呈现不活动视图控制器,如下面的代码所述。
- (void) applicationDidTimeout:(NSNotification *) notif
NSLog(@"Application Did Timeout ...");
BCDSessionInactivityViewController *sessionView=[[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"InactivityViewController"];
sessionView.modalPresentationStyle = UIModalPresentationFormSheet;
sessionView.preferredContentSize = CGSizeMake(838,340);
UIViewController *parentController = self.parentViewController;
NSLog(@"presenting view controller is %@", [parentController class]);
[[self topViewController]presentViewController:sessionView animated:YES completion:nil];
- (UIViewController *)topViewController
return [self topViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
- (UIViewController *)topViewController:(UIViewController *)rootViewController
if (rootViewController.presentedViewController == nil)
return rootViewController;
if ([rootViewController.presentedViewController isMemberOfClass:[UINavigationController class]])
UINavigationController *navigationController = (UINavigationController *)rootViewController.presentedViewController;
UIViewController *lastViewController = [[navigationController viewControllers] lastObject];
return [self topViewController:lastViewController];
UIViewController *presentedViewController = (UIViewController *)rootViewController.presentedViewController;
return [self topViewController:presentedViewController];
有什么方法可以让我也解散控制器 B 吗?
在我关闭视图控制器 C 的视图控制器 C 方法中,我根据建议编辑代码,但视图控制器 B 仍然没有被关闭。
- (IBAction)logoutbtn:(id)sender
NSLog(@"logout is called");
if ([self.presentingViewController isKindOfClass:[BCDScanReviewViewController class]] || [[[F7CheckScanner instance]checkFrontScanned] isEqualToString:@"checkFrontScanned"])
NSLog(@"check front scanned %@",[[F7CheckScanner instance]checkFrontScanned]);
[[F7CheckScanner instance]scanBackOfCheckNoData];
[sessionTimer invalidate];
sessionTimer = nil;
[[BCDTimeManager sharedTimerInstance]stopIdleTimer];
[self dismissViewControllerAnimated:YES completion:^()
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:^();
BCDThankYouViewController *thankuView=[[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"ThankyouView"];
[[self topViewController ]presentViewController:thankuView animated:YES completion:nil];
];
];
UIViewController *parentController = self.presentingViewController;
NSLog(@"presenting view controller is %@", [parentController class]);
// [self dismissViewControllerAnimated:YES completion:^()
// [parentController performSegueWithIdentifier:COMMON_VC_TO_THANK_YOU_VC sender:self];
// ];
【问题讨论】:
由于您使用的是 NavigationController,因此您可以使用unwind
segue。见答案here。
使用dismissViewControllerAnimated方法的完成块,在那里你可以再次调用ViewController B的dismissViewControllerAnimated。
@iamyogish;我已经编辑了问题,它没有按照建议工作。你能看看我是不是做错了什么
【参考方案1】:
你可以从C
做类似的事情,
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:nil];
或
[self dismissViewControllerAnimated:YES completion:^ /* do something when the animation is completed */ ];
[self.parentViewController dismissViewControllerAnimated:YES completion:^ /* do something when the animation is completed */ ];
根据评论更新:
更换你的
[self dismissViewControllerAnimated:YES completion:^()
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:^();
BCDThankYouViewController *thankuView=[[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"ThankyouView"];
[[self topViewController ]presentViewController:thankuView animated:YES completion:nil];
];
];
与
[self.presentingViewController.presentingViewController dismissViewControllerAnimated:YES completion:nil];
//you can do something here in completion instead of nil.
如果你想关闭三个视图控制器,那么你可以使用self.presentingViewController.presentingViewController.presentingViewController
。
希望这会有所帮助:)
【讨论】:
@ Lion :我在 Viewcontroller C 中有以下方法可以解除 C,在这里我根据您的评论添加了代码。但它没有解除控制器 B。你能看看这个吗?我已经编辑了问题【参考方案2】:这样解雇
//remove
[self removeFromParentViewController];
[self didMoveToParentViewController:nil];
[self.view removeFromSuperview];
【讨论】:
【参考方案3】:感谢大家的建议。我在其他 SO 帖子的帮助下解决了这个问题。这是解决方案
-(void)dismissModalStack
UIViewController *vc = self.presentingViewController;
while (vc.presentingViewController)
vc = vc.presentingViewController;
NSLog(@"Dismissing the view controller at root of view hiearchy: %@", [vc class]);
[vc dismissViewControllerAnimated:YES completion:^()
BCDThankYouViewController *thankuView=[[UIStoryboard storyboardWithName:@"Main" bundle:nil] instantiateViewControllerWithIdentifier:@"ThankyouView"];
[[self topViewController ]presentViewController:thankuView animated:YES completion:nil];
];
【讨论】:
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