在 iOS 7 中更改后退按钮会禁用滑动导航

Question

我有一个 iOS 7 应用程序，我在其中设置了一个自定义后退按钮，如下所示：

    UIImage *backButtonImage = [UIImage imageNamed:@"back-button"];
    UIButton *backButton = [UIButton buttonWithType:UIButtonTypeCustom];

    [backButton setImage:backButtonImage forState:UIControlStateNormal];
    backButton.frame = CGRectMake(0, 0, 20, 20);

    [backButton addTarget:self
                   action:@selector(popViewController)
         forControlEvents:UIControlEventTouchUpInside];

    UIBarButtonItem *backBarButtonItem = [[UIBarButtonItem alloc] initWithCustomView:backButton];
    viewController.navigationItem.leftBarButtonItem = backBarButtonItem;

但这会禁用 iOS 7 的“从左向右滑动”手势导航到上一个控制器。有谁知道我如何设置自定义按钮并保持启用此手势？

编辑： 我尝试改为设置 viewController.navigationItem.backBarButtonItem，但这似乎没有显示我的自定义图像。

Answer 1

试试self.navigationController.interactivePopGestureRecognizer.enabled = YES;

Answer 2

重要提示： 这是一个黑客。我建议看看这个answer。

在分配leftBarButtonItem 后调用以下行对我有用：

self.navigationController.interactivePopGestureRecognizer.delegate = self;

编辑： 如果在 init 方法中调用，这将不起作用。它应该在viewDidLoad 或类似的方法中调用。

Answer 3

我还隐藏了后退按钮，将其替换为自定义 leftBarItem。
推送操作后删除 interactivePopGestureRecognizer 委托对我有用：

[self.navigationController pushViewController:vcToPush animated:YES];

// Enabling iOS 7 screen-edge-pan-gesture for pop action
if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {
    self.navigationController.interactivePopGestureRecognizer.delegate = nil;
}

Answer 4

我用

[[UINavigationBar appearance] setBackIndicatorImage:[UIImage imageNamed:@"nav_back.png"]];
[[UINavigationBar appearance] setBackIndicatorTransitionMaskImage:[UIImage imageNamed:@"nav_back.png"]];

[UIBarButtonItem.appearance setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -64) forBarMetrics:UIBarMetricsDefault];

Answer 5

我看到了这个解决方案http://keighl.com/post/ios7-interactive-pop-gesture-custom-back-button/，它是 UINavigationController 的子类。它是一个更好的解决方案，因为它可以处理您在控制器就位之前滑动的情况 - 这会导致崩溃。

除此之外，我注意到如果您在根视图控制器上滑动（按下一个，然后再次返回），UI 会变得无响应（上面的答案也是同样的问题）。

所以子类 UINavigationController 中的代码应该如下所示：

@implementation NavigationController

- (void)viewDidLoad {
    [super viewDidLoad];
    __weak NavigationController *weakSelf = self;

    if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)]) {
        self.interactivePopGestureRecognizer.delegate = weakSelf;
        self.delegate = weakSelf;
    }
}

- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated {
    // Hijack the push method to disable the gesture
    if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)]) {
        self.interactivePopGestureRecognizer.enabled = NO;
    }
    [super pushViewController:viewController animated:animated];
}

#pragma mark - UINavigationControllerDelegate

- (void)navigationController:(UINavigationController *)navigationController didShowViewController:(UIViewController *)viewController animated:(BOOL)animate {
    // Enable the gesture again once the new controller is shown
    self.interactivePopGestureRecognizer.enabled = ([self respondsToSelector:@selector(interactivePopGestureRecognizer)] && [self.viewControllers count] > 1);
}

@end

Answer 6

尽可能使用 UINavigationBar 的 backIndicatorImage 和 backIndicatorTransitionMaskImage 属性。在 UIAppearanceProxy 上设置这些可以轻松修改整个应用程序的行为。皱纹是你只能在 ios 7 上设置这些，但因为你只能在 ios 7 上使用 pop 手势，所以这很有效。您的正常 ios 6 样式可以保持不变。

UINavigationBar* appearanceNavigationBar = [UINavigationBar appearance];
//the appearanceProxy returns NO, so ask the class directly
if ([[UINavigationBar class] instancesRespondToSelector:@selector(setBackIndicatorImage:)])
{
    appearanceNavigationBar.backIndicatorImage = [UIImage imageNamed:@"back"];
    appearanceNavigationBar.backIndicatorTransitionMaskImage = [UIImage imageNamed:@"back"];
    //sets back button color
    appearanceNavigationBar.tintColor = [UIColor whiteColor];
}else{
    //do ios 6 customization
}

试图操纵 interactivePopGestureRecognizer 的委托会导致很多问题。

Answer 7

navigationController.interactivePopGestureRecognizer.delegate = (id<UIGestureRecognizerDelegate>)self;

这是来自http://stuartkhall.com/posts/ios-7-development-tips-tricks-hacks，但它会导致几个错误：

1. 从屏幕左边缘滑入时，将另一个 viewController 推入 navigationController；
2. 或者，当topViewController从navigationController弹出时，从屏幕左边缘滑入；

例如当navigationController 的rootViewController 显示出来时，从屏幕左边缘向内滑动，然后点击某个东西（QUICKLY）将另一个ViewController 推入navigationController，然后

• rootViewController 不响应任何触摸事件；
• anotherViewController 不会显示；
• 再次从屏幕边缘滑动，将显示另一个ViewController；
• 点击自定义后退按钮弹出另一个ViewController，崩溃！

所以你必须像这样在self.navigationController.interactivePopGestureRecognizer.delegate 中实现UIGestureRecognizerDelegate 方法：

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
    if (gestureRecognizer == navigationController.interactivePopGestureRecognizer) {
        return !navigationController.<#TODO: isPushAnimating#> && [navigationController.viewControllers count] > 1;
    }
    return YES;
}

Answer 8

我有一个类似的问题，我将当前视图控制器分配为交互式弹出手势的委托，但会破坏任何推送的视图或导航堆栈中视图下方的视图的手势。我解决这个问题的方法是在-viewDidAppear 中设置委托，然后在-viewWillDisappear 中将其设置为nil。这使我的其他视图能够正常工作。

Answer 9

假设我们正在使用 Apple 的默认主/详细项目模板，其中 master 是一个表格视图控制器，点击它将显示详细视图控制器。

我们想要自定义出现在详细视图控制器中的后退按钮。这是如何自定义返回按钮的image、image color、text、文字颜色和font。

---

要全局更改图像、图像颜色、文本颜色或字体，请将以下内容放在一个名为在创建任何视图控制器之前的位置（例如，application:didFinishLaunchingWithOptions: 是一个不错的选择）地点）。

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    UINavigationBar* navigationBarAppearance = [UINavigationBar appearance];

    // change the back button, using default tint color
    navigationBarAppearance.backIndicatorImage = [UIImage imageNamed:@"back"];
    navigationBarAppearance.backIndicatorTransitionMaskImage = [UIImage imageNamed:@"back"];

    // change the back button, using the color inside the original image
    navigationBarAppearance.backIndicatorImage = [[UIImage imageNamed:@"back"] imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];
    navigationBarAppearance.backIndicatorTransitionMaskImage = [UIImage imageNamed:@"back"];

    // change the tint color of everything in a navigation bar
    navigationBarAppearance.tintColor = [UIColor greenColor];

    // change the font in all toolbar buttons
    NSDictionary *barButtonTitleTextAttributes =
    @{
      NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue-Light" size:12.0],
      NSForegroundColorAttributeName: [UIColor purpleColor]
      };

    [[UIBarButtonItem appearance] setTitleTextAttributes:barButtonTitleTextAttributes forState:UIControlStateNormal];

    return YES;
}

注意，您可以使用appearanceWhenContainedIn: 更好地控制哪些视图控制器受这些更改的影响，但请记住，您不能传递[DetailViewController class]，因为它包含在 UINavigationController 中，而不是您的 DetailViewController .这意味着如果您想更好地控制受影响的内容，您将需要继承 UINavigationController。

要自定义特定后退按钮项的文本或字体/颜色，您必须在 MasterViewController（而不是 DetailViewController！）中进行。这似乎不直观，因为该按钮出现在 DetailViewController 上。但是，一旦您了解自定义它的方法是通过在 navigationItem 上设置属性，它就开始变得更有意义了。

- (void)viewDidLoad { // MASTER view controller
    [super viewDidLoad];

    UIBarButtonItem *buttonItem = [[UIBarButtonItem alloc] initWithTitle:@"Testing"
                                                                   style:UIBarButtonItemStylePlain
                                                                  target:nil
                                                                  action:nil];
    NSDictionary *barButtonTitleTextAttributes =
    @{
      NSFontAttributeName: [UIFont fontWithName:@"HelveticaNeue-Light" size:12.0],
      NSForegroundColorAttributeName: [UIColor purpleColor]
      };
    [buttonItem setTitleTextAttributes:barButtonTitleTextAttributes forState:UIControlStateNormal];
    self.navigationItem.backBarButtonItem = buttonItem;
}

注意：在设置 self.navigationItem.backBarButtonItem 之后尝试设置 titleTextAttributes 似乎不起作用，因此必须在将值分配给此属性之前设置它们。

Answer 10

这个不是我写的，但是下面的博客帮了我很多，解决了我自定义导航按钮的问题：

http://keighl.com/post/ios7-interactive-pop-gesture-custom-back-button/

总之，他实现了一个使用弹出手势委托的自定义 UINavigationController。非常干净和便携！

代码：

@interface CBNavigationController : UINavigationController <UINavigationControllerDelegate, UIGestureRecognizerDelegate>
@end

@implementation CBNavigationController

- (void)viewDidLoad
{
  __weak CBNavigationController *weakSelf = self;

  if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)])
  {
    self.interactivePopGestureRecognizer.delegate = weakSelf;
    self.delegate = weakSelf;
  }
}

// Hijack the push method to disable the gesture

- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
  if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)])
    self.interactivePopGestureRecognizer.enabled = NO;

  [super pushViewController:viewController animated:animated];
}

#pragma mark UINavigationControllerDelegate

- (void)navigationController:(UINavigationController *)navigationController
       didShowViewController:(UIViewController *)viewController
                    animated:(BOOL)animate
{
  // Enable the gesture again once the new controller is shown

  if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)])
    self.interactivePopGestureRecognizer.enabled = YES;
}

编辑。修复了用户尝试在根视图控制器上向左滑动时出现的问题：

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {

    if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)] &&
        self.topViewController == [self.viewControllers firstObject] &&
        gestureRecognizer == self.interactivePopGestureRecognizer) {

        return NO;
    }

    return YES;
}

Answer 11

创建一个类“TTNavigationViewController”，它是“UINavigationController”的子类，并在故事板/类中创建该类的现有导航控制器，类中的示例代码 -

    class TTNavigationViewController: UINavigationController, UIGestureRecognizerDelegate {

override func viewDidLoad() {
    super.viewDidLoad()
    self.setNavigationBarHidden(true, animated: false)

    // enable slide-back
    if self.responds(to: #selector(getter: UINavigationController.interactivePopGestureRecognizer)) {
        self.interactivePopGestureRecognizer?.isEnabled = true
        self.interactivePopGestureRecognizer?.delegate  = self
    }
}

func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
    return true
}}

Answer 12

这里是Nick H247's answer的swift3版本

class NavigationController: UINavigationController {
  override func viewDidLoad() {
    super.viewDidLoad()
    if responds(to: #selector(getter: interactivePopGestureRecognizer)) {
      interactivePopGestureRecognizer?.delegate = self
      delegate = self
    }
  }

  override func pushViewController(_ viewController: UIViewController, animated: Bool) {
    if responds(to: #selector(getter: interactivePopGestureRecognizer)) {
      interactivePopGestureRecognizer?.isEnabled = false
    }
    super.pushViewController(viewController, animated: animated)
  }
}

extension NavigationController: UINavigationControllerDelegate {
  func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
    interactivePopGestureRecognizer?.isEnabled = (responds(to: #selector(getter: interactivePopGestureRecognizer)) && viewControllers.count > 1)
  }
}

extension NavigationController: UIGestureRecognizerDelegate {}

Answer 13

根视图

override func viewDidAppear(_ animated: Bool) {
    self.navigationController?.interactivePopGestureRecognizer?.isEnabled = false
}

子视图

override func viewDidLoad() {
    self.navigationController?.interactivePopGestureRecognizer?.isEnabled = true
    self.navigationController?.interactivePopGestureRecognizer?.delegate = self
} 

extension ChildViewController: UIGestureRecognizerDelegate {}

Answer 14

使用此逻辑来保持启用或禁用滑动手势..

- (void)navigationController:(UINavigationController *)navigationController
       didShowViewController:(UIViewController *)viewController
                    animated:(BOOL)animate
{
    if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)])
    {
        if (self.navigationController.viewControllers.count > 1)
        {
            self.navigationController.interactivePopGestureRecognizer.enabled = YES;
        }
        else
        {
            self.navigationController.interactivePopGestureRecognizer.enabled = NO;
        }
    }
}