protected virtual void OnEnable()
        {
            //this appears to happen when leaving playmode
            try
            {
                if (serializedObject == null)
                {
                    return;
                }
            }
            catch (Exception)
            {
                return;
            }

            upIcon        = FungusEditorResources.Up;
            downIcon      = FungusEditorResources.Down;
            addIcon       = FungusEditorResources.Add;
            duplicateIcon = FungusEditorResources.Duplicate;
            deleteIcon    = FungusEditorResources.Delete;

            commandListProperty = serializedObject.FindProperty("commandList");

            commandListAdaptor = new CommandListAdaptor(target as Block, commandListProperty);
        }
        public virtual void DrawBlockGUI(Flowchart flowchart)
        {
            serializedObject.Update();

            // Execute any queued cut, copy, paste, etc. operations from the prevous GUI update
            // We need to defer applying these operations until the following update because
            // the ReorderableList control emits GUI errors if you clear the list in the same frame
            // as drawing the control (e.g. select all and then delete)
            if (Event.current.type == EventType.Layout)
            {
                foreach (Action action in actionList)
                {
                    if (action != null)
                    {
                        action();
                    }
                }
                actionList.Clear();
            }

            var block = target as Block;

            SerializedProperty commandListProperty = serializedObject.FindProperty("commandList");

            if (block == flowchart.SelectedBlock)
            {
                SerializedProperty descriptionProp = serializedObject.FindProperty("description");
                EditorGUILayout.PropertyField(descriptionProp);

                DrawEventHandlerGUI(flowchart);

                block.UpdateIndentLevels();

                // Make sure each command has a reference to its parent block
                foreach (var command in block.CommandList)
                {
                    if (command == null) // Will be deleted from the list later on
                    {
                        continue;
                    }
                    command.ParentBlock = block;
                }

                ReorderableListGUI.Title("Commands");
                CommandListAdaptor adaptor = new CommandListAdaptor(commandListProperty, 0);
                adaptor.nodeRect = block._NodeRect;

                ReorderableListFlags flags = ReorderableListFlags.HideAddButton | ReorderableListFlags.HideRemoveButtons | ReorderableListFlags.DisableContextMenu;

                if (block.CommandList.Count == 0)
                {
                    EditorGUILayout.HelpBox("Press the + button below to add a command to the list.", MessageType.Info);
                }
                else
                {
                    ReorderableListControl.DrawControlFromState(adaptor, null, flags);
                }

                // EventType.contextClick doesn't register since we moved the Block Editor to be inside
                // a GUI Area, no idea why. As a workaround we just check for right click instead.
                if (Event.current.type == EventType.MouseUp &&
                    Event.current.button == 1)
                {
                    ShowContextMenu();
                    Event.current.Use();
                }

                if (GUIUtility.keyboardControl == 0) //Only call keyboard shortcuts when not typing in a text field
                {
                    Event e = Event.current;

                    // Copy keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Copy")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Copy")
                    {
                        actionList.Add(Copy);
                        e.Use();
                    }

                    // Cut keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Cut")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Cut")
                    {
                        actionList.Add(Cut);
                        e.Use();
                    }

                    // Paste keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Paste")
                    {
                        CommandCopyBuffer commandCopyBuffer = CommandCopyBuffer.GetInstance();
                        if (commandCopyBuffer.HasCommands())
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Paste")
                    {
                        actionList.Add(Paste);
                        e.Use();
                    }

                    // Duplicate keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Duplicate")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Duplicate")
                    {
                        actionList.Add(Copy);
                        actionList.Add(Paste);
                        e.Use();
                    }

                    // Delete keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Delete")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Delete")
                    {
                        actionList.Add(Delete);
                        e.Use();
                    }

                    // SelectAll keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "SelectAll")
                    {
                        e.Use();
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "SelectAll")
                    {
                        actionList.Add(SelectAll);
                        e.Use();
                    }
                }
            }

            // Remove any null entries in the command list.
            // This can happen when a command class is deleted or renamed.
            for (int i = commandListProperty.arraySize - 1; i >= 0; --i)
            {
                SerializedProperty commandProperty = commandListProperty.GetArrayElementAtIndex(i);
                if (commandProperty.objectReferenceValue == null)
                {
                    commandListProperty.DeleteArrayElementAtIndex(i);
                }
            }

            serializedObject.ApplyModifiedProperties();
        }
        public virtual void DrawBlockGUI(Flowchart flowchart)
        {
            serializedObject.Update();

            // Execute any queued cut, copy, paste, etc. operations from the prevous GUI update
            // We need to defer applying these operations until the following update because
            // the ReorderableList control emits GUI errors if you clear the list in the same frame
            // as drawing the control (e.g. select all and then delete)
            if (Event.current.type == EventType.Layout)
            {
                foreach (Action action in actionList)
                {
                    if (action != null)
                    {
                        action();
                    }
                }
                actionList.Clear();
            }

            var block = target as Block;

            SerializedProperty commandListProperty = serializedObject.FindProperty("commandList");
            
            if (block == flowchart.SelectedBlock)
            {
                // Custom tinting
                SerializedProperty useCustomTintProp = serializedObject.FindProperty("useCustomTint");
                SerializedProperty tintProp = serializedObject.FindProperty("tint");

                EditorGUILayout.BeginHorizontal();

                useCustomTintProp.boolValue = GUILayout.Toggle(useCustomTintProp.boolValue, " Custom Tint");
                if (useCustomTintProp.boolValue)
                {
                    EditorGUILayout.PropertyField(tintProp, GUIContent.none);
                }

                EditorGUILayout.EndHorizontal();

                SerializedProperty descriptionProp = serializedObject.FindProperty("description");
                EditorGUILayout.PropertyField(descriptionProp);

                DrawEventHandlerGUI(flowchart);
                
                block.UpdateIndentLevels();

                // Make sure each command has a reference to its parent block
                foreach (var command in block.CommandList)
                {
                    if (command == null) // Will be deleted from the list later on
                    {
                        continue;
                    }
                    command.ParentBlock = block;
                }

                ReorderableListGUI.Title("Commands");
                CommandListAdaptor adaptor = new CommandListAdaptor(commandListProperty, 0);
                adaptor.nodeRect = block._NodeRect;
                
                ReorderableListFlags flags = ReorderableListFlags.HideAddButton | ReorderableListFlags.HideRemoveButtons | ReorderableListFlags.DisableContextMenu;

                if (block.CommandList.Count == 0)
                {
                    EditorGUILayout.HelpBox("Press the + button below to add a command to the list.", MessageType.Info);
                }
                else
                {
                    ReorderableListControl.DrawControlFromState(adaptor, null, flags);
                }

                // EventType.contextClick doesn't register since we moved the Block Editor to be inside
                // a GUI Area, no idea why. As a workaround we just check for right click instead.
                if (Event.current.type == EventType.mouseUp &&
                    Event.current.button == 1)
                {
                    ShowContextMenu();
                    Event.current.Use();
                }

                if (GUIUtility.keyboardControl == 0) //Only call keyboard shortcuts when not typing in a text field
                {
                    Event e = Event.current;
                    
                    // Copy keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Copy")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Copy")      
                    {
                        actionList.Add(Copy);
                        e.Use();
                    }
                    
                    // Cut keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Cut")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Cut")
                    {
                        actionList.Add(Cut);
                        e.Use();
                    }
                    
                    // Paste keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Paste")
                    {
                        CommandCopyBuffer commandCopyBuffer = CommandCopyBuffer.GetInstance();
                        if (commandCopyBuffer.HasCommands())
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Paste")     
                    {
                        actionList.Add(Paste);
                        e.Use();
                    }
                    
                    // Duplicate keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Duplicate")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Duplicate")     
                    {
                        actionList.Add(Copy);
                        actionList.Add(Paste);
                        e.Use();
                    }
                    
                    // Delete keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "Delete")
                    {
                        if (flowchart.SelectedCommands.Count > 0)
                        {
                            e.Use();
                        }
                    }

                    if (e.type == EventType.ExecuteCommand && e.commandName == "Delete")        
                    {
                        actionList.Add(Delete);
                        e.Use();
                    }
                    
                    // SelectAll keyboard shortcut
                    if (e.type == EventType.ValidateCommand && e.commandName == "SelectAll")
                    {
                        e.Use();
                    }
                
                    if (e.type == EventType.ExecuteCommand && e.commandName == "SelectAll")     
                    {
                        actionList.Add(SelectAll);
                        e.Use();
                    }               
                }
            }

            // Remove any null entries in the command list.
            // This can happen when a command class is deleted or renamed.
            for (int i = commandListProperty.arraySize - 1; i >= 0; --i)
            {
                SerializedProperty commandProperty = commandListProperty.GetArrayElementAtIndex(i);
                if (commandProperty.objectReferenceValue == null)
                {
                    commandListProperty.DeleteArrayElementAtIndex(i);
                }
            }

            serializedObject.ApplyModifiedProperties();
        }