ExternalWindow reports an error on mac

I try to use the engine without the player.I’m working with wxWidgets + Urho3D and I use a wxPanel as the externalwindow.Below are the parameters of the engine I set.

engineParameters_["ResourcePaths"] = "Data;CoreData";
	engineParameters_["LogName"] = "wxUrho3D.log";
	engineParameters_["ExternalWindow"] = panel->GetHandle();
	engineParameters_["FullScreen"] = false;
	engineParameters_["WindowResizable"] = true;
	engineParameters_["WindowWidth"] = 1280;
	engineParameters_["WindowHeight"] = 720;

It works well in windows,and the player is also hidden.But an error will be reported on the mac.The following is the error message on the mac.

if anyone can give me some suggestions or tell me the correct usage of externalwindow,I will be grateful.

Yep , it’s a known issue
You will have to do some modifications on the SDL side to make it work.
Look at the link below , it should be a good start

Thank you very much for your suggestion,I will try it later.