stride3d/stride · error · ArgumentNullException

ArgumentNullException: nodeContainer

Error message

ArgumentNullException: nodeContainer

What it means

The protected PropertiesViewModel constructor requires a NodeContainer that provides access to the inspected object's property nodes, and throws ArgumentNullException when it is null. The container is stored and used to create the GraphViewModelService.

Solutions

1. Pass the valid NodeContainer from the session/asset node system
2. Obtain it via NodeContainerFactory/ISessionService before constructing the view model
3. Initialize the node container earlier in the view-model construction chain

Example fix

// before
public MyPropertiesViewModel(IViewModelServiceProvider sp) : base(sp, GetContainer()) { }
// after
public MyPropertiesViewModel(IViewModelServiceProvider sp) : base(sp, GetContainer() ?? throw new InvalidOperationException("NodeContainer not available")) { }

if (nodeContainer == null) throw new InvalidOperationException("NodeContainer must be resolved before creating PropertiesViewModel");

static bool HasNodeContainer([NotNullWhen(true)] NodeContainer? nc) => nc is not null;

try { base(serviceProvider, nodeContainer); } catch (ArgumentNullException ex) { logger.LogCritical(ex, "NodeContainer missing in PropertiesViewModel"); throw; }

When it happens

Trigger: Deriving from PropertiesViewModel and calling the base constructor with nodeContainer == null.

Common situations: Building a custom properties/editor view model where the NodeContainer came from an unresolved session or a not-yet-initialized node system.

Related errors

• entity must contain a non-null asset entity.
• ArgumentNullException: templates
• ArgumentNullException: dependencyManager
• ArgumentNullException: deletedObjects
• ArgumentNullException: removeAction

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/8450c9b5279f3941. Report an issue: GitHub.

Appendix: source

Thrown at sources/editor/Stride.Core.Assets.Editor/Components/Properties/PropertiesViewModel.cs:44

    {
        protected readonly GraphViewModelService ViewModelService;
        protected readonly NodeContainer NodeContainer;
        private readonly object lockObject = new object();

        private GraphViewModel viewModel;
        private bool canDisplayProperties;
        private string fallbackMessage;
        private int currentToken;

        /// <summary>
        /// Initializes a new instance of the <see cref="PropertiesViewModel"/> class.
        /// </summary>
        /// <param name="serviceProvider">The view model service provider to use.</param>
        /// <param name="nodeContainer">The <see cref="NodeContainer"/> containing the nodes used to access object properties.</param>
        protected PropertiesViewModel([NotNull] IViewModelServiceProvider serviceProvider, [NotNull] NodeContainer nodeContainer)
            : base(serviceProvider)
        {
            if (nodeContainer == null) throw new ArgumentNullException(nameof(nodeContainer));
            NodeContainer = nodeContainer;

            // Create the service needed to manage graph view models
            ViewModelService = new GraphViewModelService(nodeContainer);

            // Update the service provider of this view model to contains the GraphViewModelService we created.
            ServiceProvider = new ViewModelServiceProvider(serviceProvider, ViewModelService.Yield());

            RegisterNodePresenterCommand(new CreateNewInstanceCommand());
            RegisterNodePresenterCommand(new AddNewItemCommand());
            RegisterNodePresenterCommand(new AddPrimitiveKeyCommand());
            RegisterNodePresenterCommand(new RemoveItemCommand());
            RegisterNodePresenterCommand(new RenameStringKeyCommand());
            RegisterNodePresenterCommand(new MoveItemCommand());
            RegisterNodePresenterCommand(new FlagEnumSelectAllCommand());
            RegisterNodePresenterCommand(new FlagEnumSelectNoneCommand());
            RegisterNodePresenterCommand(new FlagEnumSelectInvertCommand());

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