iOS 禁用或开启屏幕左滑动返回

• (void)viewDidAppear:(BOOL)animated {

   [super viewDidAppear:animated];
  
  //禁用屏幕左滑返回手势
  
  if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)])
  
    self.navigationController.interactivePopGestureRecognizer.enabled = NO;
  

  }

- (void)viewDidDisappear:(BOOL)animated {

  [super viewDidDisappear:animated];

  //开启

 self.navigationController.interactivePopGestureRecognizer.enabled = YES;

}