我遇到了几个案例，现在可以方便地找到“最顶层”的视图控制器（负责当前视图的控制器），但还没有找到办法。
基本上挑战是这样的：假设一个 在一个不是视图控制器的类中执行 （或一个视图） [和没有活动视图的地址] 并且还没有传递最顶层视图控制器的地址（或者说，导航控制器的地址），是否可以找到该视图控制器？ （如果是这样，怎么样？）
或者，如果失败，是否可以找到最顶层的视图？
答案 0 :(得分：404)
我认为您需要结合已接受的答案和@ fishstix的
+ (UIViewController*) topMostController
{
UIViewController *topController = [UIApplication sharedApplication].keyWindow.rootViewController;
while (topController.presentedViewController) {
topController = topController.presentedViewController;
}
return topController;
}
Swift 3.0 +
func topMostController() -> UIViewController? {
guard let window = UIApplication.shared.keyWindow, let rootViewController = window.rootViewController else {
return nil
}
var topController = rootViewController
while let newTopController = topController.presentedViewController {
topController = newTopController
}
return topController
}
答案 1 :(得分：149)
要完成JonasG＆＃39; answer（在遍历时遗漏了标签栏控制器），这是我返回当前可见视图控制器的版本：
- (UIViewController*)topViewController {
return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
}
- (UIViewController*)topViewControllerWithRootViewController:(UIViewController*)rootViewController {
if ([rootViewController isKindOfClass:[UITabBarController class]]) {
UITabBarController* tabBarController = (UITabBarController*)rootViewController;
return [self topViewControllerWithRootViewController:tabBarController.selectedViewController];
} else if ([rootViewController isKindOfClass:[UINavigationController class]]) {
UINavigationController* navigationController = (UINavigationController*)rootViewController;
return [self topViewControllerWithRootViewController:navigationController.visibleViewController];
} else if (rootViewController.presentedViewController) {
UIViewController* presentedViewController = rootViewController.presentedViewController;
return [self topViewControllerWithRootViewController:presentedViewController];
} else {
return rootViewController;
}
}
答案 2 :(得分：80)
iOS 4在UIWindow上引入了rootViewController属性：
[UIApplication sharedApplication].keyWindow.rootViewController;
您需要在创建视图控制器之后自己设置它。
答案 3 :(得分：42)
完整的非递归版本，负责不同的场景：
UINavigationController UITabBarController <强>目标C
UIViewController *topViewController = self.window.rootViewController;
while (true)
{
if (topViewController.presentedViewController) {
topViewController = topViewController.presentedViewController;
} else if ([topViewController isKindOfClass:[UINavigationController class]]) {
UINavigationController *nav = (UINavigationController *)topViewController;
topViewController = nav.topViewController;
} else if ([topViewController isKindOfClass:[UITabBarController class]]) {
UITabBarController *tab = (UITabBarController *)topViewController;
topViewController = tab.selectedViewController;
} else {
break;
}
}
Swift 4 +
extension UIWindow {
func topViewController() -> UIViewController? {
var top = self.rootViewController
while true {
if let presented = top?.presentedViewController {
top = presented
} else if let nav = top as? UINavigationController {
top = nav.visibleViewController
} else if let tab = top as? UITabBarController {
top = tab.selectedViewController
} else {
break
}
}
return top
}
}
答案 4 :(得分：27)
使用扩展程序获取Swift的最顶层视图控制器
代码：
extension UIViewController {
@objc func topMostViewController() -> UIViewController {
// Handling Modal views
if let presentedViewController = self.presentedViewController {
return presentedViewController.topMostViewController()
}
// Handling UIViewController's added as subviews to some other views.
else {
for view in self.view.subviews
{
// Key property which most of us are unaware of / rarely use.
if let subViewController = view.next {
if subViewController is UIViewController {
let viewController = subViewController as! UIViewController
return viewController.topMostViewController()
}
}
}
return self
}
}
}
extension UITabBarController {
override func topMostViewController() -> UIViewController {
return self.selectedViewController!.topMostViewController()
}
}
extension UINavigationController {
override func topMostViewController() -> UIViewController {
return self.visibleViewController!.topMostViewController()
}
}
<强>用法：
UIApplication.sharedApplication().keyWindow!.rootViewController!.topMostViewController()
答案 5 :(得分：24)
要完成Eric的answer（在浏览过程中遗漏了弹出窗口，导航控制器，tabbarcontrollers，视图控制器作为子视图添加到其他视图控制器），这是我返回当前可见视图控制器的版本：
=============================================== ======================
- (UIViewController*)topViewController {
return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
}
- (UIViewController*)topViewControllerWithRootViewController:(UIViewController*)viewController {
if ([viewController isKindOfClass:[UITabBarController class]]) {
UITabBarController* tabBarController = (UITabBarController*)viewController;
return [self topViewControllerWithRootViewController:tabBarController.selectedViewController];
} else if ([viewController isKindOfClass:[UINavigationController class]]) {
UINavigationController* navContObj = (UINavigationController*)viewController;
return [self topViewControllerWithRootViewController:navContObj.visibleViewController];
} else if (viewController.presentedViewController && !viewController.presentedViewController.isBeingDismissed) {
UIViewController* presentedViewController = viewController.presentedViewController;
return [self topViewControllerWithRootViewController:presentedViewController];
}
else {
for (UIView *view in [viewController.view subviews])
{
id subViewController = [view nextResponder];
if ( subViewController && [subViewController isKindOfClass:[UIViewController class]])
{
if ([(UIViewController *)subViewController presentedViewController] && ![subViewController presentedViewController].isBeingDismissed) {
return [self topViewControllerWithRootViewController:[(UIViewController *)subViewController presentedViewController]];
}
}
}
return viewController;
}
}
=============================================== ======================
现在你需要做的就是获得最顶层的视图控制器，调用上面的方法如下：
UIViewController *topMostViewControllerObj = [self topViewController];
答案 6 :(得分：20)
此答案包括childViewControllers，并保持清晰易读的实施。
+ (UIViewController *)topViewController
{
UIViewController *rootViewController = [UIApplication sharedApplication].keyWindow.rootViewController;
return [rootViewController topVisibleViewController];
}
- (UIViewController *)topVisibleViewController
{
if ([self isKindOfClass:[UITabBarController class]])
{
UITabBarController *tabBarController = (UITabBarController *)self;
return [tabBarController.selectedViewController topVisibleViewController];
}
else if ([self isKindOfClass:[UINavigationController class]])
{
UINavigationController *navigationController = (UINavigationController *)self;
return [navigationController.visibleViewController topVisibleViewController];
}
else if (self.presentedViewController)
{
return [self.presentedViewController topVisibleViewController];
}
else if (self.childViewControllers.count > 0)
{
return [self.childViewControllers.lastObject topVisibleViewController];
}
return self;
}
答案 7 :(得分：13)
我最近在我的一个项目中遇到了这种情况，当网络状态发生变化时，需要显示控制器显示的通知视图以及任何类型（UINavigationController，经典控制器或自定义视图控制器）。
所以我juste发布了我的代码，这很简单并且实际上基于协议，因此它对每种类型的容器控制器都很灵活。 它似乎与最后的答案有关，但是以一种非常灵活的方式。
您可以在此处获取代码：PPTopMostController
使用
获得最多的控制器UIViewController *c = [UIViewController topMostController];
答案 8 :(得分：11)
这是对Eric的回答的改进：
UIViewController *_topMostController(UIViewController *cont) {
UIViewController *topController = cont;
while (topController.presentedViewController) {
topController = topController.presentedViewController;
}
if ([topController isKindOfClass:[UINavigationController class]]) {
UIViewController *visible = ((UINavigationController *)topController).visibleViewController;
if (visible) {
topController = visible;
}
}
return (topController != cont ? topController : nil);
}
UIViewController *topMostController() {
UIViewController *topController = [UIApplication sharedApplication].keyWindow.rootViewController;
UIViewController *next = nil;
while ((next = _topMostController(topController)) != nil) {
topController = next;
}
return topController;
}
_topMostController(UIViewController *cont)是辅助函数。
现在您需要做的就是调用topMostController()并返回最顶层的UIViewController！
答案 9 :(得分：8)
Swift中UIApplication的简单扩展名：
注意：
它关注moreNavigationController
UITabBarController
extension UIApplication {
class func topViewController(baseViewController: UIViewController? = UIApplication.sharedApplication().keyWindow?.rootViewController) -> UIViewController? {
if let navigationController = baseViewController as? UINavigationController {
return topViewController(navigationController.visibleViewController)
}
if let tabBarViewController = baseViewController as? UITabBarController {
let moreNavigationController = tabBarViewController.moreNavigationController
if let topViewController = moreNavigationController.topViewController where topViewController.view.window != nil {
return topViewController(topViewController)
} else if let selectedViewController = tabBarViewController.selectedViewController {
return topViewController(selectedViewController)
}
}
if let splitViewController = baseViewController as? UISplitViewController where splitViewController.viewControllers.count == 1 {
return topViewController(splitViewController.viewControllers[0])
}
if let presentedViewController = baseViewController?.presentedViewController {
return topViewController(presentedViewController)
}
return baseViewController
}
}
简单用法：
if let topViewController = UIApplication.topViewController() {
//do sth with top view controller
}
答案 10 :(得分：8)
- (UIViewController*)topViewController {
return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
}
- (UIViewController*)topViewControllerWithRootViewController:(UIViewController*)rootViewController {
if ([rootViewController isKindOfClass:[UITabBarController class]]) {
UITabBarController* tabBarController = (UITabBarController*)rootViewController;
return [self topViewControllerWithRootViewController:tabBarController.selectedViewController];
} else if ([rootViewController isKindOfClass:[UINavigationController class]]) {
UINavigationController* navigationController = (UINavigationController*)rootViewController;
return [self topViewControllerWithRootViewController:navigationController.visibleViewController];
} else if (rootViewController.presentedViewController) {
UIViewController* presentedViewController = rootViewController.presentedViewController;
return [self topViewControllerWithRootViewController:presentedViewController];
} else {
return rootViewController;
}
}
答案 11 :(得分：7)
@implementation UIWindow (Extensions)
- (UIViewController*) topMostController
{
UIViewController *topController = [self rootViewController];
while (topController.presentedViewController) {
topController = topController.presentedViewController;
}
return topController;
}
@end
答案 12 :(得分：7)
最新的Swift版本：
创建一个文件，将其命名为UIWindowExtension.swift并粘贴以下代码段：
import UIKit
public extension UIWindow {
public var visibleViewController: UIViewController? {
return UIWindow.getVisibleViewControllerFrom(self.rootViewController)
}
public static func getVisibleViewControllerFrom(vc: UIViewController?) -> UIViewController? {
if let nc = vc as? UINavigationController {
return UIWindow.getVisibleViewControllerFrom(nc.visibleViewController)
} else if let tc = vc as? UITabBarController {
return UIWindow.getVisibleViewControllerFrom(tc.selectedViewController)
} else {
if let pvc = vc?.presentedViewController {
return UIWindow.getVisibleViewControllerFrom(pvc)
} else {
return vc
}
}
}
}
func getTopViewController() -> UIViewController? {
let appDelegate = UIApplication.sharedApplication().delegate
if let window = appDelegate!.window {
return window?.visibleViewController
}
return nil
}
在任何地方使用它：
if let topVC = getTopViewController() {
}
答案 13 :(得分：7)
这是我对此的看法。感谢@Stakenborg指出了跳过让UIAlertView成为最顶级控制器的方法
-(UIWindow *) returnWindowWithWindowLevelNormal
{
NSArray *windows = [UIApplication sharedApplication].windows;
for(UIWindow *topWindow in windows)
{
if (topWindow.windowLevel == UIWindowLevelNormal)
return topWindow;
}
return [UIApplication sharedApplication].keyWindow;
}
-(UIViewController *) getTopMostController
{
UIWindow *topWindow = [UIApplication sharedApplication].keyWindow;
if (topWindow.windowLevel != UIWindowLevelNormal)
{
topWindow = [self returnWindowWithWindowLevelNormal];
}
UIViewController *topController = topWindow.rootViewController;
if(topController == nil)
{
topWindow = [UIApplication sharedApplication].delegate.window;
if (topWindow.windowLevel != UIWindowLevelNormal)
{
topWindow = [self returnWindowWithWindowLevelNormal];
}
topController = topWindow.rootViewController;
}
while(topController.presentedViewController)
{
topController = topController.presentedViewController;
}
if([topController isKindOfClass:[UINavigationController class]])
{
UINavigationController *nav = (UINavigationController*)topController;
topController = [nav.viewControllers lastObject];
while(topController.presentedViewController)
{
topController = topController.presentedViewController;
}
}
return topController;
}
答案 14 :(得分：3)
扩展@ Eric的答案，你需要注意keyWindow实际上是你想要的窗口。例如，如果您在警报视图中点击某些内容后尝试使用此方法，则keyWindow实际上将成为警报的窗口，这无疑会给您带来问题。当通过警报处理深度链接并导致SIGABRT没有堆栈跟踪时，这发生在我的野外。要调试的总婊子。
这是我现在使用的代码：
- (UIViewController *)getTopMostViewController {
UIWindow *topWindow = [UIApplication sharedApplication].keyWindow;
if (topWindow.windowLevel != UIWindowLevelNormal) {
NSArray *windows = [UIApplication sharedApplication].windows;
for(topWindow in windows)
{
if (topWindow.windowLevel == UIWindowLevelNormal)
break;
}
}
UIViewController *topViewController = topWindow.rootViewController;
while (topViewController.presentedViewController) {
topViewController = topViewController.presentedViewController;
}
return topViewController;
}
随意从这个问题的其他答案中检索您喜欢的顶视图控制器的风格。
答案 15 :(得分：3)
我知道它很晚了，可能是多余的。但是以下是我想出的代码段，对我来说很有用：
static func topViewController() -> UIViewController? {
return topViewController(vc: UIApplication.shared.keyWindow?.rootViewController)
}
private static func topViewController(vc:UIViewController?) -> UIViewController? {
if let rootVC = vc {
guard let presentedVC = rootVC.presentedViewController else {
return rootVC
}
if let presentedNavVC = presentedVC as? UINavigationController {
let lastVC = presentedNavVC.viewControllers.last
return topViewController(vc: lastVC)
}
return topViewController(vc: presentedVC)
}
return nil
}
答案 16 :(得分：3)
extension UIApplication {
class func topViewController(controller: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController? {
if let navigationController = controller as? UINavigationController {
return topViewController(controller: navigationController.visibleViewController)
}
if let tabController = controller as? UITabBarController {
if let selected = tabController.selectedViewController {
return topViewController(controller: selected)
}
}
if let presented = controller?.presentedViewController {
return topViewController(controller: presented)
}
return controller
}
}
从任何地方使用它，
UIApplication.topViewController()?.present(yourController, animated: true, completion: nil)
或类似
UIApplication.topViewController()?
.navigationController?
.popToViewController(yourController,
animated: true)
适合任何类，例如UINavigationController，UITabBarController
享受！
答案 17 :(得分：3)
此解决方案是最完整的。它需要考虑： UINavigationController的 UIPageViewController 的UITabBarController 最顶层的视图控制器来自顶视图控制器
示例在Swift 3中。
有3次重载
//Get the topmost view controller for the current application.
public func MGGetTopMostViewController() -> UIViewController? {
if let currentWindow:UIWindow = UIApplication.shared.keyWindow {
return MGGetTopMostViewController(fromWindow: currentWindow)
}
return nil
}
//Gets the topmost view controller from a specific window.
public func MGGetTopMostViewController(fromWindow window:UIWindow) -> UIViewController? {
if let rootViewController:UIViewController = window.rootViewController
{
return MGGetTopMostViewController(fromViewController: rootViewController)
}
return nil
}
//Gets the topmost view controller starting from a specific UIViewController
//Pass the rootViewController into this to get the apps top most view controller
public func MGGetTopMostViewController(fromViewController viewController:UIViewController) -> UIViewController {
//UINavigationController
if let navigationViewController:UINavigationController = viewController as? UINavigationController {
let viewControllers:[UIViewController] = navigationViewController.viewControllers
if navigationViewController.viewControllers.count >= 1 {
return MGGetTopMostViewController(fromViewController: viewControllers[viewControllers.count - 1])
}
}
//UIPageViewController
if let pageViewController:UIPageViewController = viewController as? UIPageViewController {
if let viewControllers:[UIViewController] = pageViewController.viewControllers {
if viewControllers.count >= 1 {
return MGGetTopMostViewController(fromViewController: viewControllers[0])
}
}
}
//UITabViewController
if let tabBarController:UITabBarController = viewController as? UITabBarController {
if let selectedViewController:UIViewController = tabBarController.selectedViewController {
return MGGetTopMostViewController(fromViewController: selectedViewController)
}
}
//Lastly, Attempt to get the topmost presented view controller
var presentedViewController:UIViewController! = viewController.presentedViewController
var nextPresentedViewController:UIViewController! = presentedViewController?.presentedViewController
//If there is a presented view controller, get the top most prensentedViewController and return it.
if presentedViewController != nil {
while nextPresentedViewController != nil {
//Set the presented view controller as the next one.
presentedViewController = nextPresentedViewController
//Attempt to get the next presented view controller
nextPresentedViewController = presentedViewController.presentedViewController
}
return presentedViewController
}
//If there is no topmost presented view controller, return the view controller itself.
return viewController
}
答案 18 :(得分：3)
又一个Swift解决方案
func topController() -> UIViewController? {
// recursive follow
func follow(from:UIViewController?) -> UIViewController? {
if let to = (from as? UITabBarController)?.selectedViewController {
return follow(to)
} else if let to = (from as? UINavigationController)?.visibleViewController {
return follow(to)
} else if let to = from?.presentedViewController {
return follow(to)
}
return from
}
let root = UIApplication.sharedApplication().keyWindow?.rootViewController
return follow(root)
}
答案 19 :(得分：3)
替代Swift解决方案：
static func topMostController() -> UIViewController {
var topController = UIApplication.sharedApplication().keyWindow?.rootViewController
while (topController?.presentedViewController != nil) {
topController = topController?.presentedViewController
}
return topController!
}
答案 20 :(得分：3)
这对我有用。
我发现有时控制器在关键窗口上是零，因为keyWindow是一些操作系统，如警报等。
+ (UIViewController*)topMostController
{
UIWindow *topWndow = [UIApplication sharedApplication].keyWindow;
UIViewController *topController = topWndow.rootViewController;
if (topController == nil)
{
// The windows in the array are ordered from back to front by window level; thus,
// the last window in the array is on top of all other app windows.
for (UIWindow *aWndow in [[UIApplication sharedApplication].windows reverseObjectEnumerator])
{
topController = aWndow.rootViewController;
if (topController)
break;
}
}
while (topController.presentedViewController) {
topController = topController.presentedViewController;
}
return topController;
}
答案 21 :(得分：2)
我认为大多数答案都完全忽略了UINavigationViewController，所以我通过以下实现处理了这个用例。
+ (UIViewController *)topMostController {
UIViewController * topController = [UIApplication sharedApplication].keyWindow.rootViewController;
while (topController.presentedViewController || [topController isMemberOfClass:[UINavigationController class]]) {
if([topController isMemberOfClass:[UINavigationController class]]) {
topController = [topController childViewControllers].lastObject;
} else {
topController = topController.presentedViewController;
}
}
return topController;
}
答案 22 :(得分：2)
Swift的绝佳解决方案，在AppDelegate中实现
func getTopViewController()->UIViewController{
return topViewControllerWithRootViewController(UIApplication.sharedApplication().keyWindow!.rootViewController!)
}
func topViewControllerWithRootViewController(rootViewController:UIViewController)->UIViewController{
if rootViewController is UITabBarController{
let tabBarController = rootViewController as! UITabBarController
return topViewControllerWithRootViewController(tabBarController.selectedViewController!)
}
if rootViewController is UINavigationController{
let navBarController = rootViewController as! UINavigationController
return topViewControllerWithRootViewController(navBarController.visibleViewController)
}
if let presentedViewController = rootViewController.presentedViewController {
return topViewControllerWithRootViewController(presentedViewController)
}
return rootViewController
}
答案 23 :(得分：1)
夫特：
extension UIWindow {
func visibleViewController() -> UIViewController? {
if let rootViewController: UIViewController = self.rootViewController {
return UIWindow.getVisibleViewControllerFrom(rootViewController)
}
return nil
}
class func getVisibleViewControllerFrom(vc:UIViewController) -> UIViewController {
if vc.isKindOfClass(UINavigationController.self) {
let navigationController = vc as UINavigationController
return UIWindow.getVisibleViewControllerFrom( navigationController.visibleViewController)
} else if vc.isKindOfClass(UITabBarController.self) {
let tabBarController = vc as UITabBarController
return UIWindow.getVisibleViewControllerFrom(tabBarController.selectedViewController!)
} else {
if let presentedViewController = vc.presentedViewController {
return UIWindow.getVisibleViewControllerFrom(presentedViewController.presentedViewController!)
} else {
return vc;
}
}
}
用法：
if let topController = window.visibleViewController() {
println(topController)
}
答案 24 :(得分：1)
使用以下扩展名抓取当前可见的UIViewController。适用于Swift 4.0及更高版本
代码：
extension UIApplication {
class func topViewController(_ viewController: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController? {
if let nav = viewController as? UINavigationController {
return topViewController(nav.visibleViewController)
}
if let tab = viewController as? UITabBarController {
if let selected = tab.selectedViewController {
return topViewController(selected)
}
}
if let presented = viewController?.presentedViewController {
return topViewController(presented)
}
return viewController
}
}
如何使用？
let objViewcontroller = UIApplication.topViewController()
答案 25 :(得分：1)
很多这些答案都不完整。虽然这是在Objective-C中，但这是我现在可以组合在一起的所有这些的最佳编译，作为非递归块：
链接到Gist ，如果它被修改：https://gist.github.com/benguild/0d149bb3caaabea2dac3d2dca58c0816
代码供参考/比较：
UIViewController *(^topmostViewControllerForFrontmostNormalLevelWindow)(void) = ^UIViewController *{
// NOTE: Adapted from various stray answers here:
// https://stackoverflow.com/questions/6131205/iphone-how-to-find-topmost-view-controller/20515681
UIViewController *viewController;
for (UIWindow *window in UIApplication.sharedApplication.windows.reverseObjectEnumerator.allObjects) {
if (window.windowLevel == UIWindowLevelNormal) {
viewController = window.rootViewController;
break;
}
}
while (viewController != nil) {
if ([viewController isKindOfClass:[UITabBarController class]]) {
viewController = ((UITabBarController *)viewController).selectedViewController;
} else if ([viewController isKindOfClass:[UINavigationController class]]) {
viewController = ((UINavigationController *)viewController).visibleViewController;
} else if (viewController.presentedViewController != nil && !viewController.presentedViewController.isBeingDismissed) {
viewController = viewController.presentedViewController;
} else if (viewController.childViewControllers.count > 0) {
viewController = viewController.childViewControllers.lastObject;
} else {
BOOL repeat = NO;
for (UIView *view in viewController.view.subviews.reverseObjectEnumerator.allObjects) {
if ([view.nextResponder isKindOfClass:[UIViewController class]]) {
viewController = (UIViewController *)view.nextResponder;
repeat = YES;
break;
}
}
if (!repeat) {
break;
}
}
}
return viewController;
};
答案 26 :(得分：1)
另一个Swift解决方案
extension UIViewController {
static var topmostViewController: UIViewController? {
return UIApplication.sharedApplication().keyWindow?.topmostViewController
}
var topmostViewController: UIViewController? {
return presentedViewController?.topmostViewController ?? self
}
}
extension UINavigationController {
override var topmostViewController: UIViewController? {
return visibleViewController?.topmostViewController
}
}
extension UITabBarController {
override var topmostViewController: UIViewController? {
return selectedViewController?.topmostViewController
}
}
extension UIWindow {
var topmostViewController: UIViewController? {
return rootViewController?.topmostViewController
}
}
答案 27 :(得分：1)
以下两个函数可以帮助在Stack of view控制器上找到topViewController。您可能需要稍后进行自定义，但是对于此代码来说，了解topViewController或viewControllers堆栈的概念非常棒。
- (UIViewController*)findTopViewController {
id topControler = [self topMostController];
UIViewController* topViewController;
if([topControler isKindOfClass:[UINavigationController class]]) {
topViewController = [[(UINavigationController*)topControler viewControllers] lastObject];
} else if ([topControler isKindOfClass:[UITabBarController class]]) {
//Here you can get reference of top viewcontroller from stack of viewcontrollers on UITabBarController
} else {
//topController is a preented viewController
topViewController = (UIViewController*)topControler;
}
//NSLog(@"Top ViewController is: %@",NSStringFromClass([topController class]));
return topViewController;
}
- (UIViewController*)topMostController
{
UIViewController *topController = [UIApplication sharedApplication].keyWindow.rootViewController;
while (topController.presentedViewController) {
topController = topController.presentedViewController;
}
//NSLog(@"Top View is: %@",NSStringFromClass([topController class]));
return topController;
}
您可以使用[viewController Class]方法找出viewController的类类型。
答案 28 :(得分：1)
不确定这是否有助于您通过查找最顶层的视图控制器来实现您的目标，但我试图提供一个新的视图控制器，但如果我的根视图控制器已经有一个模态对话框，它将被阻止，所以我会使用这段代码循环到所有模态视图控制器的顶部：
UIViewController* parentController =[UIApplication sharedApplication].keyWindow.rootViewController;
while( parentController.presentedViewController &&
parentController != parentController.presentedViewController )
{
parentController = parentController.presentedViewController;
}
答案 29 :(得分：0)
如果根控制器是导航控制器，找到顶部可见控制器的正确方法是：
UIViewController *rootVC = [[UIApplication sharedApplication] keyWindow].rootViewController;
if ([rootVC respondsToSelector:@selector(visibleViewController)])
{
UIViewController *topVC = [(UINavigationController *)rootVC visibleViewController];
// do your thing with topVC
}
以下是UINavigationController.h的摘录：
@property(nonatomic,readonly,retain) UIViewController *topViewController; // The top view controller on the stack.
@property(nonatomic,readonly,retain) UIViewController *visibleViewController; // Return modal view controller if it exists. Otherwise the top view controller.
答案 30 :(得分：0)
这是一个Swift实现的应用程序，以UINavigationController为根。
if let nav = UIApplication.sharedApplication().keyWindow?.rootViewController as? UINavigationController{
//get the current's navigation view controller
var vc = nav.topViewController
while vc?.presentedViewController != nil {
vc = vc?.presentedViewController
}
return vc
}
答案 31 :(得分：0)
另一个解决方案依赖于响应者链，根据第一响应者的不同，响应者链可能会起作用，也可能不起作用：
伪代码示例：
+ (UIViewController *)currentViewController {
UIView *firstResponder = [self firstResponder]; // from the first link above, but not guaranteed to return a UIView, so this should be handled more appropriately.
UIViewController *viewController = [firstResponder viewController]; // from the second link above
return viewController;
}
答案 32 :(得分：0)
这非常适合从任何根视图控制器中查找顶级视图Controller 1
答案 33 :(得分：0)
您可以使用
找到最顶层的视图控制器NSArray *arrViewControllers=[[self navigationController] viewControllers];
UIViewController *topMostViewController=(UIViewController *)[arrViewControllers objectAtIndex:[arrViewControllers count]-1];
答案 34 :(得分：0)
我认为来自Rajesh的解决方案几乎是完美的，但我认为从上到下更好的遍历子视图，我更改为以下内容：
+ (UIViewController *)topViewController:(UIViewController *)viewController{
if (viewController.presentedViewController)
{
UIViewController *presentedViewController = viewController.presentedViewController;
return [self topViewController:presentedViewController];
}
else if ([viewController isKindOfClass:[UITabBarController class]])
{
UITabBarController *tabBarController = (UITabBarController *)viewController;
return [self topViewController:tabBarController.selectedViewController];
}
else if ([viewController isKindOfClass:[UINavigationController class]])
{
UINavigationController *navController = (UINavigationController *)viewController;
return [self topViewController:navController.visibleViewController];
}
// Handling UIViewController's added as subviews to some other views.
else {
NSInteger subCount = [viewController.view subviews].count - 1;
for (NSInteger index = subCount; index >=0 ; --index)
{
UIView *view = [[viewController.view subviews] objectAtIndex:index];
id subViewController = [view nextResponder]; // Key property which most of us are unaware of / rarely use.
if ( subViewController && [subViewController isKindOfClass:[UIViewController class]])
{
return [self topViewController:subViewController];
}
}
return viewController;
}
}
答案 35 :(得分：0)
以前的答案似乎没有处理rootController是UITabBarController或UINavigationController的情况。
以下是swift中适用于这些情况的函数：
func getCurrentView() -> UIViewController?
{
if let window = UIApplication.sharedApplication().keyWindow, var currentView: UIViewController = window.rootViewController
{
while (currentView.presentedViewController != nil)
{
if let presented = currentView.presentedViewController
{
currentView = presented
}
}
if currentView is UITabBarController
{
if let visible = (currentView as! UITabBarController).selectedViewController
{
currentView = visible;
}
}
if currentView is UINavigationController
{
if let visible = (currentView as! UINavigationController).visibleViewController
{
currentView = visible;
}
}
return currentView
}
return nil
}
答案 36 :(得分：0)
我认为这里可能忽略了一件事。也许最好将父viewController传递给使用viewController的函数。如果要在视图层次结构中四处寻找，可能会发现顶视图控制器可能违反了Model层和UI层的分离，并且有代码味。只是指出这一点，我做了同样的事情，然后意识到通过将模型操作返回到我对视图控制器有引用的UI层，将其传递给函数要简单得多。
答案 37 :(得分：0)
Swift 4.2中简洁而全面的解决方案，其中考虑了 UINavigationControllers ， UITabBarControllers ，已呈现和子级查看控制器：
extension UIViewController {
func topmostViewController() -> UIViewController {
if let navigationVC = self as? UINavigationController,
let topVC = navigationVC.topViewController {
return topVC.topmostViewController()
}
if let tabBarVC = self as? UITabBarController,
let selectedVC = tabBarVC.selectedViewController {
return selectedVC.topmostViewController()
}
if let presentedVC = presentedViewController {
return presentedVC.topmostViewController()
}
if let childVC = children.last {
return childVC.topmostViewController()
}
return self
}
}
extension UIApplication {
func topmostViewController() -> UIViewController? {
return keyWindow?.rootViewController?.topmostViewController()
}
}
用法：
let viewController = UIApplication.shared.topmostViewController()
答案 38 :(得分：0)
我的问题与我在应用程序中使用SWRevealViewController有点不同。 我使用了Yuchen Zhong的answer，但它始终将topViewController作为SWRevealViewController返回。对于那些使用SWRevealViewController或其他Pod来开发sideMenu的用户。这是我对Yuchen Zhong答案的扩展：
INSERT INTO CANDYINVENTORY (CANDY, SOLD) VALUES('POLARICE',1);
答案 39 :(得分：0)
为了避免很多复杂性，我通过在委托中创建一个viewController并在每个viewDidLoad方法中将其设置为self来跟踪当前的viewController，这样每当你加载一个新的视图时，在委托中保存的ViewController将对应于那个视图的viewController。这可能很难看，但是效果非常好，并且不需要导航控制器或任何废话。
答案 40 :(得分：-2)
您应该使用：
[UIApplication sharedApplication].window.rootViewController;
当[UIApplication sharedApplication].keyWindow上有uiactionsheet时，this answer中提到的使用keyWindow是不对的。