从导航堆栈中删除视图控制器
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【中文标题】从导航堆栈中删除视图控制器【英文标题】：Removing viewcontrollers from navigation stack 【发布时间】：2012-05-04 02:58:07 【问题描述】：我有一个导航堆栈，比如 5 个 UIViewController。我想通过单击第 5 个视图控制器中的按钮来删除堆栈中的第 3 和第 4 个视图控制器。是否有可能做到这一点？如果有怎么办？
【问题讨论】：
【参考方案1】：Swift 5.4
删除SpecificViewController
navigationController.viewControllers.removeAll $0 is SpecificViewController
【讨论】：
【参考方案2】：Swift 5、Xcode 13
我发现这种方法很简单，只需指定要从导航堆栈中删除的视图控制器。
extension UINavigationController
func removeViewController(_ controller: UIViewController.Type)
if let viewController = viewControllers.first(where: $0.isKind(of: controller.self) )
viewController.removeFromParent()
使用示例：
navigationController.removeViewController(YourViewController.self)
【讨论】：
【参考方案3】：使用此代码并享受：
NSMutableArray *navigationArray = [[NSMutableArray alloc] initWithArray: self.navigationController.viewControllers];
// [navigationArray removeAllObjects]; // This is just for remove all view controller from navigation stack.
[navigationArray removeObjectAtIndex: 2]; // You can pass your index here
self.navigationController.viewControllers = navigationArray;
[navigationArray release];
希望这会对你有所帮助。
编辑：Swift 代码
guard let navigationController = self.navigationController else return
var navigationArray = navigationController.viewControllers // To get all UIViewController stack as Array
navigationArray.remove(at: navigationArray.count - 2) // To remove previous UIViewController
self.navigationController?.viewControllers = navigationArray
编辑：移除除最后一个之外的所有 ViewController -> 左上角没有返回按钮
guard let navigationController = self.navigationController else return
var navigationArray = navigationController.viewControllers // To get all UIViewController stack as Array
let temp = navigationArray.last
navigationArray.removeAll()
navigationArray.append(temp!) //To remove all previous UIViewController except the last one
self.navigationController?.viewControllers = navigationArray
【讨论】：
我已经绑定了这个并且不起作用。有人告诉我，与属性有关的事情导致它不释放视图控制器。 这在 ios 适用于 iOS 8！ Vivek : 告诉我你尝试过什么，并有礼貌地在投反对票之前考虑一下。 此方法确实从堆栈中删除了一个视图控制器，但似乎还有一个不受影响的导航项堆栈。我在 ios 8.4 中得到的行为是这样的：假设我们有控制器 1 2 3 4 5。我删除了 4，显示在 5 上的后退按钮不受影响。我点击返回，它显示 3 但标题为 4。我再次点击返回，它显示 3，标题为 3【参考方案4】：// 按类名从堆栈中删除视图控制器，然后关闭当前视图。
self.navigationController?.viewControllers.removeAll(where: (vc) -> Bool in
if vc.isKind(of: ViewController.self) || vc.isKind(of: ViewController2.self)
return true
else
return false
)
self.navigationController?.popViewController(animated: false)
self.dismiss(animated: true, completion: nil)
【讨论】：
【参考方案5】：详情
Swift 5.1，Xcode 11.3.1解决方案
extension UIViewController
func removeFromNavigationController() navigationController?.removeController(.last) self == $0
extension UINavigationController
enum ViewControllerPosition case first, last
enum ViewControllersGroupPosition case first, last, all
func removeController(_ position: ViewControllerPosition, animated: Bool = true,
where closure: (UIViewController) -> Bool)
var index: Int?
switch position
case .first: index = viewControllers.firstIndex(where: closure)
case .last: index = viewControllers.lastIndex(where: closure)
if let index = index removeControllers(animated: animated, in: Range(index...index))
func removeControllers(_ position: ViewControllersGroupPosition, animated: Bool = true,
where closure: (UIViewController) -> Bool)
var range: Range<Int>?
switch position
case .first: range = viewControllers.firstRange(where: closure)
case .last:
guard let _range = viewControllers.reversed().firstRange(where: closure) else return
let count = viewControllers.count - 1
range = .init(uncheckedBounds: (lower: count - _range.min()!, upper: count - _range.max()!))
case .all:
let viewControllers = self.viewControllers.filter !closure($0)
setViewControllers(viewControllers, animated: animated)
return
if let range = range removeControllers(animated: animated, in: range)
func removeControllers(animated: Bool = true, in range: Range<Int>)
var viewControllers = self.viewControllers
viewControllers.removeSubrange(range)
setViewControllers(viewControllers, animated: animated)
func removeControllers(animated: Bool = true, in range: ClosedRange<Int>)
removeControllers(animated: animated, in: Range(range))
private extension Array
func firstRange(where closure: (Element) -> Bool) -> Range<Int>?
guard var index = firstIndex(where: closure) else return nil
var indexes = [Int]()
while index < count && closure(self[index])
indexes.append(index)
index += 1
if indexes.isEmpty return nil
return Range<Int>(indexes.min()!...indexes.max()!)
用法
removeFromParent()
navigationController?.removeControllers(in: 1...3)
navigationController?.removeController(.first) $0 != self
navigationController?.removeController(.last) $0 != self
navigationController?.removeControllers(.all) $0.isKind(of: ViewController.self)
navigationController?.removeControllers(.first) !$0.isKind(of: ViewController.self)
navigationController?.removeControllers(.last) $0 != self
完整样本
不要忘记在此处粘贴解决方案代码
import UIKit
class ViewController2: ViewController
class ViewController: UIViewController
private var tag: Int = 0
deinit print("____ DEINITED: \(self), tag: \(tag)" )
override func viewDidLoad()
super.viewDidLoad()
print("____ INITED: \(self)")
let stackView = UIStackView()
stackView.axis = .vertical
view.addSubview(stackView)
stackView.translatesAutoresizingMaskIntoConstraints = false
stackView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
stackView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
stackView.addArrangedSubview(createButton(text: "Push ViewController() white", selector: #selector(pushWhiteViewController)))
stackView.addArrangedSubview(createButton(text: "Push ViewController() gray", selector: #selector(pushGrayViewController)))
stackView.addArrangedSubview(createButton(text: "Push ViewController2() green", selector: #selector(pushController2)))
stackView.addArrangedSubview(createButton(text: "Push & remove previous VC", selector: #selector(pushViewControllerAndRemovePrevious)))
stackView.addArrangedSubview(createButton(text: "Remove first gray VC", selector: #selector(dropFirstGrayViewController)))
stackView.addArrangedSubview(createButton(text: "Remove last gray VC", selector: #selector(dropLastGrayViewController)))
stackView.addArrangedSubview(createButton(text: "Remove all gray VCs", selector: #selector(removeAllGrayViewControllers)))
stackView.addArrangedSubview(createButton(text: "Remove all VCs exept Last", selector: #selector(removeAllViewControllersExeptLast)))
stackView.addArrangedSubview(createButton(text: "Remove all exept first and last VCs", selector: #selector(removeAllViewControllersExeptFirstAndLast)))
stackView.addArrangedSubview(createButton(text: "Remove all ViewController2()", selector: #selector(removeAllViewControllers2)))
stackView.addArrangedSubview(createButton(text: "Remove first VCs where bg != .gray", selector: #selector(dropFirstViewControllers)))
stackView.addArrangedSubview(createButton(text: "Remove last VCs where bg == .gray", selector: #selector(dropLastViewControllers)))
override func viewWillAppear(_ animated: Bool)
super.viewWillAppear(animated)
if title?.isEmpty ?? true title = "First"
private func createButton(text: String, selector: Selector) -> UIButton
let button = UIButton()
button.setTitle(text, for: .normal)
button.setTitleColor(.blue, for: .normal)
button.addTarget(self, action: selector, for: .touchUpInside)
return button
extension ViewController
private func createViewController<VC: ViewController>(backgroundColor: UIColor = .white) -> VC
let viewController = VC()
let counter = (navigationController?.viewControllers.count ?? -1 ) + 1
viewController.tag = counter
viewController.title = "Controller \(counter)"
viewController.view.backgroundColor = backgroundColor
return viewController
@objc func pushWhiteViewController()
navigationController?.pushViewController(createViewController(), animated: true)
@objc func pushGrayViewController()
navigationController?.pushViewController(createViewController(backgroundColor: .lightGray), animated: true)
@objc func pushController2()
navigationController?.pushViewController(createViewController(backgroundColor: .green) as ViewController2, animated: true)
@objc func pushViewControllerAndRemovePrevious()
navigationController?.pushViewController(createViewController(), animated: true)
removeFromNavigationController()
@objc func removeAllGrayViewControllers()
navigationController?.removeControllers(.all) $0.view.backgroundColor == .lightGray
@objc func removeAllViewControllersExeptLast()
navigationController?.removeControllers(.all) $0 != self
@objc func removeAllViewControllersExeptFirstAndLast()
guard let navigationController = navigationController, navigationController.viewControllers.count > 1 else return
let lastIndex = navigationController.viewControllers.count - 1
navigationController.removeControllers(in: 1..<lastIndex)
@objc func removeAllViewControllers2()
navigationController?.removeControllers(.all) $0.isKind(of: ViewController2.self)
@objc func dropFirstViewControllers()
navigationController?.removeControllers(.first) $0.view.backgroundColor != .lightGray
@objc func dropLastViewControllers()
navigationController?.removeControllers(.last) $0.view.backgroundColor == .lightGray
@objc func dropFirstGrayViewController()
navigationController?.removeController(.first) $0.view.backgroundColor == .lightGray
@objc func dropLastGrayViewController()
navigationController?.removeController(.last) $0.view.backgroundColor == .lightGray
结果
【讨论】：
【参考方案6】：斯威夫特 5：
navigationController?.viewControllers.removeAll(where: (vc) -> Bool in
if vc.isKind(of: MyViewController.self) || vc.isKind(of: MyViewController2.self)
return false
else
return true
)
【讨论】：
return !vc.isKind(of: MyViewController.self) && !vc.isKind(of: MyViewController2.self) 会在一行中完成这项工作:-)【参考方案7】：
Swift 5.1，Xcode 11
extension UINavigationController
public func removePreviousController(total: Int)
let totalViewControllers = self.viewControllers.count
self.viewControllers.removeSubrange(totalViewControllers-total..<totalViewControllers - 1)
确保在前一个控制器的 viewDidDisappear() 或新控制器的 viewDidAppear() 之后调用此实用程序函数
【讨论】：
【参考方案8】：除非另有说明，否则我使用方法编写了一个扩展，该方法删除了 root 和 top 之间的所有控制器。
extension UINavigationController
func removeControllers(between start: UIViewController?, end: UIViewController?)
guard viewControllers.count > 1 else return
let startIndex: Int
if let start = start
guard let index = viewControllers.index(of: start) else
return
startIndex = index
else
startIndex = 0
let endIndex: Int
if let end = end
guard let index = viewControllers.index(of: end) else
return
endIndex = index
else
endIndex = viewControllers.count - 1
let range = startIndex + 1 ..< endIndex
viewControllers.removeSubrange(range)
如果你想使用范围（例如：2 到 5）你可以使用
let range = 2 ..< 5
viewControllers.removeSubrange(range)
在 iOS 12.2、Swift 5 上测试
【讨论】：
【参考方案9】：Swift 3 & 4/5
self.navigationController!.viewControllers.removeAll()
self.navigationController?.viewControllers.remove(at: "insert here a number")
斯威夫特 2.1
全部删除：
self.navigationController!.viewControllers.removeAll()
在索引处删除
self.navigationController?.viewControllers.removeAtIndex("insert here a number")
还有很多可能的操作，例如 removeFirst、range 等。
【讨论】：
看了你的回答，我对我的项目工作流程有了一个想法。非常感谢。 这会删除它自己的 NavigationController，而不是清理一堆视图控制器【参考方案10】：使用UINavigationController 中的setViewControllers 函数是最好的方法。还有animated参数可以开启动画。
func setViewControllers(_ viewControllers: [UIViewController], animated: Bool)
快速提问示例
func goToFifthVC()
var currentVCStack = self.navigationController?.viewControllers
currentVCStack?.removeSubrange(2...3)
let fifthVC = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "fifthVC")
currentVCStack?.append(fifthVC)
self.navigationController?.setViewControllers(currentVCStack!, animated: true)
我尝试了其他方式，例如[tempVC removeFromParentViewController];。它做出了奇怪的行为，删除了 ViewController 导航，当弹出时仍然显示 @robin-ellerkmann 报告的那样
【讨论】：
这实际上是最好的解决方案：从navigationController?.viewControllers 数组中移除VC，并使用setViewControllers 分配新数组。我还检查了僵尸或参考循环，它是安全的。 我确认这是一个很好的解决方案：我实际上在两个方面都使用了setViewControllers(_:animated:) 技术：弹出多个控制器和推送多个控制器。【参考方案11】：
这个解决方案在 swift 4 中对我有用：
let VCCount = self.navigationController!.viewControllers.count
self.navigationController?.viewControllers.removeSubrange(Range(VCCount-3..<VCCount - 1))
您当前在堆栈中的视图控制器索引是：
self.navigationController!.viewControllers.count - 1
【讨论】：
【参考方案12】：使用这个
if let navVCsCount = navigationController?.viewControllers.count
navigationController?.viewControllers.removeSubrange(Range(2..<navVCsCount - 1))
它会处理 navigationController 的 ViewControllers。 viewControllers 以及一个在 navigationBar 中堆叠的 navigationItems。
注意：请务必至少在 viewDidAppear 之后调用它
【讨论】：
这种方法在 Swift 5、Xcode 10.3 中对我来说非常有效......如果让 navVCsCount = navigationController?.viewControllers.count self.navigationController?.viewControllers.removeSubrange(navVCsCount-3..Swift 2.0：
var navArray:Array = (self.navigationController?.viewControllers)!
navArray.removeAtIndex(navArray.count-2)
self.navigationController?.viewControllers = navArray
【讨论】：
所以你不是强制解开导航控制器，你可以让它成为一个 if 语句if var navArray = ... ... 【参考方案14】：
你可以先获取数组中的所有视图控制器，然后与对应的视图控制器类核对后，就可以删除你想要的了。
这是一小段代码：
NSArray* tempVCA = [self.navigationController viewControllers];
for(UIViewController *tempVC in tempVCA)
if([tempVC isKindOfClass:[urViewControllerClass class]])
[tempVC removeFromParentViewController];
我认为这将使您的工作更轻松。
【讨论】：
这个可以多用途。谢谢:) 当我使用它时，控制器被正确移除。但是当我使用“返回”按钮时，我的导航栏会显示已删除的 viewController 的信息。有其他人收到这种奇怪的行为吗？我该如何解决？ @Robin Ellerkmann 你找到解决这个问题的方法了吗？我正在删除视图控制器，但后退按钮仍保留在导航栏上。 @MehmetEmre 我使用 Swift 2.1 和 self.navigationController?.viewControllers.removeLast()。这对我来说效果很好。 当我在 4 视图控制器中时，注销时所有视图控制器的内存为 80MB。内存还是80MB。所以内存没有释放。 :(【参考方案15】：如果您尝试从第 5 个视图控制器移动到第 2 个视图控制器（跳过第 3 个和第 4 个），您想使用[self.navigationController popToviewController:secondViewController]。
您可以从导航控制器堆栈中获取secondViewController。
secondViewController = [self.navigationController.viewControllers objectAtIndex:yourViewControllerIndex];
【讨论】：
不想弹出当前的视图控制器。当前的视图控制器应该保持不变。但我需要在堆栈中弹出它下面的 2 个视图控制器 @JeanPaulScott。我想知道你为什么要这样做，如果不是为了弹出？！。 有一种情况，我会将同一个视图控制器的不同实例推入堆栈。所以当一个新实例被创建并推入堆栈时，我想弹出前一个实例和与之关联的视图控制器。 @Vignesh 由于“滑动弹出”手势，这在 iOS 7 中无法按要求工作 @JeanPaulScott 来实现你想要的，最安全的方法是在推送你的新视图控制器实例之前弹出两次。以上是关于从导航堆栈中删除视图控制器的主要内容，如果未能解决你的问题，请参考以下文章