How to create and add a Flip Flop blueprint node from C++?

Development Programming & Scripting C++
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1

Hi, I’m trying to build blueprint graphs through C++ and I encountered a problem when trying to create a Flip Flop node.

The node, alongside many others, is a macro node, which means it is a “shortcut” to a subgraph that handles the logic (in this case alternating between A and B).

Here is the code for my attempt (does not work):

CreateFlipFlopNode(UEdGraph* EventGraph, FVector2D Position) {
	// Create the Flip Flop node
	UBlueprintNodeSpawner* NodeSpawner = UBlueprintNodeSpawner::Create(UK2Node_MacroInstance::StaticClass());
	UEdGraphNode* Node = NodeSpawner->Invoke(EventGraph, IBlueprintNodeBinder::FBindingSet(), Position);

	// Set up the node parameters
	UK2Node_MacroInstance* FlipFlopNode = Cast<UK2Node_MacroInstance>(Node);
	if (FlipFlopNode) {
		// TODO: Find a way to set the macro graph to flip flop's
		// UObject* Obj = StaticLoadObject(UEdGraph::StaticClass(), nullptr, *FString("/Script/Engine.EdGraph'/Engine/EditorBlueprintResources/StandardMacros.StandardMacros:FlipFlop'"));
		
		UEdGraph* Graph = Cast<UEdGraph>(Obj);
		if (Graph) {
			FlipFlopNode->SetMacroGraph(Graph);
		}
	}

	return Node;
}

Essentially, I need to find a way to get the node’s macro graph. From what I can see when copy-pasting the node into a notepad, it should be located at "/Script/Engine.EdGraph'/Engine/EditorBlueprintResources/StandardMacros.StandardMacros:FlipFlop'".

Does anyone know how I can find and retrieve the graph to spawn the correct node?

Thanks

2

Try to get a reference like this:

UObject* Obj = FSoftObjectPath("/Engine/EditorBlueprintResources/StandardMacros.StandardMacros:FlipFlop").TryLoad();
3

This looks like it works, thanks.
One small issue is that I need to refresh the node manually in the editor for the pins to appear, do you know if there is a C++ function that does that?

Edit: I looked at UEdGraphNode’s documentation and found ReconstructNode() that does the trick