問題：

當A controller作為navigationController的rootcontroller時，如果在A中向右側(cè)滑動，再push到下個界面時會出現(xiàn)界面假死。原因此時導航控制器的viewControllers的count值為1，滑動時沒有上層控制器，系統(tǒng)不知如何處理，所以會出現(xiàn)假死。

解決方法：

自定義導航控制器，實現(xiàn)如下代理

- (void)viewDidLoad {
    [super viewDidLoad];
    __weak BaseNavigationViewController *weakSelf = self;
    if ([self respondsToSelector:@selector(interactivePopGestureRecognizer)]) {
    self.interactivePopGestureRecognizer.delegate = weakSelf;
    self.delegate = weakSelf;
  }
}

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

- (NSArray *)popToRootViewControllerAnimated:(BOOL)animated {
     if ( [self respondsToSelector:@selector(interactivePopGestureRecognizer)]&& animated == YES ){
      self.interactivePopGestureRecognizer.enabled = NO;
    }
      return [super popToRootViewControllerAnimated:animated];
}

- (NSArray *)popToViewController:(UIViewController *)viewController animated:(BOOL)animated {
    if( [self respondsToSelector:@selector(interactivePopGestureRecognizer)] ){
      self.interactivePopGestureRecognizer.enabled = NO;
    }
    return [super popToViewController:viewController animated:animated];
}

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