attempt to fix #490

Author: Roberto De Ioris

Source/UnrealEnginePython/Private/PythonSmartDelegate.cpp

@@ -68,7 +68,7 @@ void FPythonSmartDelegate::PyFOnAssetPostImport(UFactory *factory, UObject *u_ob
 void FPythonSmartDelegate::PyFOnMainFrameCreationFinished(TSharedPtr<SWindow> InRootWindow, bool bIsNewProjectWindow)
 {
 	FScopePythonGIL gil;
-	PyObject *ret = PyObject_CallFunction(py_callable, (char *)"OO", py_ue_new_swidget<ue_PySWindow>(InRootWindow.ToSharedRef(), &ue_PySWindowType), bIsNewProjectWindow ? Py_True : Py_False);
+	PyObject *ret = PyObject_CallFunction(py_callable, (char *)"NO", py_ue_new_swidget<ue_PySWindow>(InRootWindow.ToSharedRef(), &ue_PySWindowType), bIsNewProjectWindow ? Py_True : Py_False);
 	if (!ret)
 	{
 		unreal_engine_py_log_error();

Source/UnrealEnginePython/Private/UEPyEditor.cpp

@@ -1824,10 +1824,8 @@ PyObject *py_unreal_engine_editor_on_asset_post_import(PyObject * self, PyObject
 	if (!PyCallable_Check(py_callable))
 		return PyErr_Format(PyExc_Exception, "object is not a callable");
 
-	// will brutally leak
-	FPythonSmartDelegate *py_delegate = new FPythonSmartDelegate();
-	py_delegate->SetPyCallable(py_callable);
-	FEditorDelegates::OnAssetPostImport.AddRaw(py_delegate, &FPythonSmartDelegate::PyFOnAssetPostImport);
+	TSharedRef<FPythonSmartDelegate> py_delegate = FUnrealEnginePythonHouseKeeper::Get()->NewPythonSmartDelegate(py_callable);
+	FEditorDelegates::OnAssetPostImport.AddSP(py_delegate, &FPythonSmartDelegate::PyFOnAssetPostImport);
 	Py_RETURN_NONE;
 }
 
@@ -1841,12 +1839,17 @@ PyObject *py_unreal_engine_on_main_frame_creation_finished(PyObject * self, PyOb
 
 	if (!PyCallable_Check(py_callable))
 		return PyErr_Format(PyExc_Exception, "object is not a callable");
+	/*
+	TSharedRef<FPythonSmartDelegate> py_delegate = FUnrealEnginePythonHouseKeeper::Get()->NewPythonSmartDelegate(py_callable);
+	IMainFrameModule& MainFrameModule = FModuleManager::LoadModuleChecked<IMainFrameModule>(TEXT("MainFrame"));
+	MainFrameModule.OnMainFrameCreationFinished().AddSP(py_delegate, &FPythonSmartDelegate::PyFOnMainFrameCreationFinished);
+	*/
 
-	// will brutally leak
 	FPythonSmartDelegate *py_delegate = new FPythonSmartDelegate();
 	py_delegate->SetPyCallable(py_callable);
 	IMainFrameModule& MainFrameModule = FModuleManager::LoadModuleChecked<IMainFrameModule>(TEXT("MainFrame"));
 	MainFrameModule.OnMainFrameCreationFinished().AddRaw(py_delegate, &FPythonSmartDelegate::PyFOnMainFrameCreationFinished);
+	
 	Py_RETURN_NONE;
 }
 

Source/UnrealEnginePython/Public/PythonHouseKeeper.h

@@ -7,6 +7,7 @@
 #include "Slate/UEPySlateDelegate.h"
 #include "Runtime/CoreUObject/Public/UObject/GCObject.h"
 #include "PythonDelegate.h"
+#include "PythonSmartDelegate.h"
 
 class FUnrealEnginePythonHouseKeeper : public FGCObject
 {
@@ -257,6 +258,16 @@ class FUnrealEnginePythonHouseKeeper : public FGCObject
 		return Delegate;
 	}
 
+	TSharedRef<FPythonSmartDelegate> NewPythonSmartDelegate(PyObject *PyCallable)
+	{
+		TSharedRef<FPythonSmartDelegate> Delegate = MakeShareable(new FPythonSmartDelegate());
+		Delegate->SetPyCallable(PyCallable);
+
+		PyStaticSmartDelegatesTracker.Add(Delegate);
+
+		return Delegate;
+	}
+
 	void TrackDeferredSlateDelegate(TSharedRef<FPythonSlateDelegate> Delegate, TSharedRef<SWidget> Owner)
 	{
 		FPythonSWidgetDelegateTracker Tracker(Delegate, Owner);
@@ -280,5 +291,7 @@ class FUnrealEnginePythonHouseKeeper : public FGCObject
 	TArray<FPythonSWidgetDelegateTracker> PySlateDelegatesTracker;
 	TArray<TSharedRef<FPythonSlateDelegate>> PyStaticSlateDelegatesTracker;
 
+	TArray<TSharedRef<FPythonSmartDelegate>> PyStaticSmartDelegatesTracker;
+
 	TArray<UObject *> PythonTrackedObjects;
 };