Fix for unuseful error

Author: PaulNonatomic

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## [0.6.5-beta] - Aug 16, 2024
 - Updated frame delay of DelayState transition to 0
+- Fix for add nodes multiple times when entering runtime
+- Fix for unuseful error thrown when sub state-machines ref is missing
 
 ## [0.6.4-beta] - Aug 12, 2024
 - Fix for rogue tilda

Editor/NodeGraph/NodeGraphStateManager.cs

@@ -77,6 +77,8 @@ public virtual void SaveState()
 
 		public void SetModel(NodeGraphDataModel model)
 		{
+			if (!model) return;
+			
 			Model = model;
 			SaveState();
 		}

Editor/NodeGraph/NodeGraphView.cs

@@ -33,8 +33,6 @@ public NodeGraphView(string id)
 
 		public virtual void PopulateGraph(NodeGraphDataModel model)
 		{
-			if (!model) return;
-			
 			StateManager.SetModel(model);
 			ClearGraph();
 		}
@@ -117,7 +115,7 @@ private void HandleModelChanged(NodeGraphDataModel model)
 			PopulateGraph(model);
 		}
 
-		private void ClearGraph()
+		protected virtual void ClearGraph()
 		{
 			DeleteElements(graphElements);
 		}

Editor/StateGraph/VisualElements/StateGraphView.cs

@@ -48,12 +48,17 @@ public void PopulateGraph(NodeGraphDataModel model, bool recentre)
 			_toolBar.SetModel(stateModel);
 			_footerBar.SetGridPosition(StateManager.GridPosition);
 			_footerBar.SetModel(stateModel);
-
+		
 			base.PopulateGraph(model);
 			AddEntryNode(stateModel);
 
+			//A delay is required to allow the entry node time to be added
 			EditorApplication.delayCall += () =>
 			{
+				//It's possible that the delayCall is invoked multiple times when entering run time
+				//This just prevents adding the nodes multiple times
+				if (nodes.ToList().Count > 0) return;
+				
 				AddNodes(stateModel);
 				AddEdges(stateModel);
 

Runtime/StateGraph/States/BaseSubStateMachineState.cs

@@ -28,28 +28,32 @@ public override void OnAwakeState()
 
 		public override void OnStartState()
 		{
-			SubStateMachine.Start();
+			SubStateMachine?.Start();
 		}
 
 		public override void OnEnterState()
 		{
+			if(SubStateMachine == null) return;
+			
 			SubStateMachine.Model.SetParent(SubStateMachine.Model);
 			SubStateMachine.OnComplete += OnSubStateComplete;
 			SubStateMachine.Enter();
 		}
 
 		public override void OnUpdateState()
 		{
-			SubStateMachine.Update();
+			SubStateMachine?.Update();
 		}
 
 		public override void OnFixedUpdateState()
 		{
-			SubStateMachine.FixedUpdate();
+			SubStateMachine?.FixedUpdate();
 		}
 
 		public override void OnExitState()
 		{
+			if(SubStateMachine == null) return;
+			
 			SubStateMachine.OnComplete -= OnSubStateComplete;
 			SubStateMachine.Exit();
 		}
@@ -58,7 +62,7 @@ public override void OnDestroyState()
 		{
 			ReplaceModelWithOriginalModel();
 
-			SubStateMachine.OnDestroy();
+			SubStateMachine?.OnDestroy();
 		}
 
 		protected virtual void CreateStateMachine()

Runtime/StateGraph/States/SubStateMachineState.cs

@@ -5,7 +5,7 @@ namespace Nonatomic.VSM2.StateGraph.States
 {
 	public class SubStateMachineState : BaseSubStateMachineState
 	{
-		[Transition]
+		[Transition(frameDelay:0)]
 		public event Action OnComplete;
 
 		protected override void OnSubStateComplete(State state, StateMachineModel model)