i use /Users/name/flutter/dev/integration_tests/ios_add2app this project to test

i only edit this file

`implementation FullScreenViewController

• (void)viewWillDisappear:(BOOL)animated {

  [super viewWillDisappear:animated];

  self.navigationController.navigationBarHidden = NO;
  self.navigationController.hidesBarsOnSwipe = NO;
  if (self.isMovingFromParentViewController) {
  // Note that if we were doing things that might cause the VC
  // to disappear (like using the image_picker plugin)
  // we shouldn't do this. But in this case we know we're
  // just going back to the navigation controller.
  // If we needed Flutter to tell us when we could actually go away,
  // we'd need to communicate over a method channel with it.
  [self.engine setViewController:nil];
  }
  }

• (void)viewDidLoad {
  [super viewDidLoad];

  UIBarButtonItem *rightBarItem = [[UIBarButtonItem alloc] initWithTitle:@"next" style:UIBarButtonItemStylePlain target:self action:@selector(next)];
  self.navigationItem.rightBarButtonItem = rightBarItem;
  }

• (void)next {

  FullScreenViewController *flutterViewController = [[FullScreenViewController alloc] init];
  [flutterViewController setInitialRoute:@"full"];
  // [[self reloadMessageChannel] sendMessage:@"full"];
  [self.navigationController
  pushViewController:flutterViewController animated:NO];
  }

• (void)dealloc {

  NSLog(@"dealloc");
  }

end`

run in simulateor will not crash but crashed in many real devices

cc @jmagman @xster

What is the crash trace and error?

What is the crash trace and error?

Thread 1 Queue : com.apple.main-thread (serial)
#0	0x0000000182990910 in objc_msgSend ()
#1	0x00000001867d96ac in +[EAGLContext setCurrentContext:] ()
#2	0x0000000104a887c4 in flutter::IOSGLRenderTarget::~IOSGLRenderTarget() ()
#3	0x0000000104a894c0 in std::__1::unique_ptr<flutter::IOSGLRenderTarget, std::__1::default_delete<flutter::IOSGLRenderTarget> >::reset(flutter::IOSGLRenderTarget*) ()
#4	0x0000000104a88d40 in flutter::IOSSurfaceGL::~IOSSurfaceGL() ()
#5	0x0000000104a88d70 in flutter::IOSSurfaceGL::~IOSSurfaceGL() ()
#6	0x0000000104a8a140 in flutter::PlatformViewIOS::SetOwnerViewController(fml::WeakPtr<FlutterViewController>) ()
#7	0x0000000104a6bf14 in -[FlutterEngine setViewController:] ()
#8	0x00000001046c4500 in -[FullScreenViewController viewWillDisappear:] at /Users/xxx/flutter/dev/integration_tests/ios_add2app/ios_add2app/FullScreenViewController.m:24
#9	0x000000018d45d79c in -[UIViewController _setViewAppearState:isAnimating:] ()
#10	0x000000018d47b998 in -[UIViewController __viewWillDisappear:] ()
#11	0x000000018d71b424 in -[UINavigationController _startCustomTransition:] ()
#12	0x000000018d48aa4c in -[UINavigationController _startDeferredTransitionIfNeeded:] ()
#13	0x000000018d48a6a4 in -[UINavigationController __viewWillLayoutSubviews] ()
#14	0x000000018d47e3a8 in -[UILayoutContainerView layoutSubviews] ()
#15	0x000000018d3d66f4 in -[UIView(CALayerDelegate) layoutSublayersOfLayer:] ()
#16	0x000000018794be54 in -[CALayer layoutSublayers] ()
#17	0x000000018794ffe4 in CA::Layer::layout_if_needed(CA::Transaction*) ()
#18	0x00000001878bc6c8 in CA::Context::commit_transaction(CA::Transaction*) ()
#19	0x00000001878e41b0 in CA::Transaction::commit() ()
#20	0x000000018d7af518 in _UIApplicationFlushRunLoopCATransactionIfTooLate ()
#21	0x000000018dd8c5d0 in __handleEventQueueInternal ()
#22	0x000000018dd85368 in __handleHIDEventFetcherDrain ()
#23	0x000000018376b404 in __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ ()
#24	0x000000018376ac2c in __CFRunLoopDoSources0 ()
#25	0x000000018376879c in __CFRunLoopRun ()
#26	0x0000000183688da8 in CFRunLoopRunSpecific ()
#27	0x000000018566e020 in GSEventRunModal ()
#28	0x000000018d6a8758 in UIApplicationMain ()
#29	0x00000001046c34f8 in main at /Users/yiche/flutter/dev/integration_tests/ios_add2app/ios_add2app/main.m:10
#30	0x0000000183119fc0 in start ()

Seems related to flutter/engine#7919. Perhaps @chinmaygarde has insights.

I also run into the same problem, any solution?

Overriding the dealloc method in a subclass of FlutterViewController, calling[EAGLContext setCurrentContext:nil]can solve this problem.

@interface XXFlutterViewController : FlutterViewController
...
@end

@implementation XXFlutterViewController
...
- (void)dealloc {
    [EAGLContext setCurrentContext:nil];
    ...
}
@end

Seems related to flutter/engine#7919. Perhaps @chinmaygarde has insights.

Overriding the dealloc method in a subclass of FlutterViewController, calling[EAGLContext setCurrentContext:nil]can solve this problem.

@interface XXFlutterViewController : FlutterViewController
...
@end

@implementation XXFlutterViewController
...
- (void)dealloc {
    [EAGLContext setCurrentContext:nil];
    ...
}
@end

非常感谢，测试真机有效，不会闪退了

We'd still like to find and solve the root issue. Leaving this bug open.

Overriding the dealloc method in a subclass of FlutterViewController, calling[EAGLContext setCurrentContext:nil]can solve this problem.

@interface XXFlutterViewController : FlutterViewController
...
@end

@implementation XXFlutterViewController
...
- (void)dealloc {
    [EAGLContext setCurrentContext:nil];
    ...
}
@end

Can someone write this code into FlutterViewController's dealloc method? It may help many other people like me.

@chinmaygarde You reviewed flutter/engine#17366, is this fixed?

Yeah. This has been fixed on ToT.

This thread has been automatically locked since there has not been any recent activity after it was closed. If you are still experiencing a similar issue, please open a new bug, including the output of flutter doctor -v and a minimal reproduction of the issue.