Unity-Technologies/UnityCsReference · error · ArgumentException

Cannot be null or empty

Error message

Cannot be null or empty

What it means

Thrown by SceneView.AddCameraMode when the name parameter is null or empty. A custom camera mode requires a non-empty display name to appear in the scene view draw mode dropdown. This is the first of two guards in AddCameraMode (name, then section).

Source

Thrown at Editor/Mono/SceneView/SceneView.cs:4635

                LookAt(pivot, lastSceneViewRotation, size, m_LastSceneViewOrtho);
                if (Tools.current == Tool.Rect)
                    Tools.current = Tool.Move;
            }

            // Let's not persist the vertex snapping mode on 2D/3D mode change
            HandleUtility.ignoreRaySnapObjects = null;
            Tools.vertexDragging = false;
            Tools.handleOffset = Vector3.zero;

            var gridSettings = GridSettings.instance;
            gridSettings.rotation = Quaternion.identity;
            gridSettings.position = Vector3.zero;
        }

        public static CameraMode AddCameraMode(string name, string section)
        {
            if (string.IsNullOrEmpty(name))
                throw new ArgumentException("Cannot be null or empty", "name");
            if (string.IsNullOrEmpty(section))
                throw new ArgumentException("Cannot be null or empty", "section");
            var newMode = new CameraMode(DrawCameraMode.UserDefined, name, section);
            if (userDefinedModes.Contains(newMode))
                throw new InvalidOperationException(string.Format("A mode named {0} already exists in section {1}", name, section));
            userDefinedModes.Add(newMode);
            return newMode;
        }

        private static bool IsValidCameraMode(CameraMode cameraMode)
        {
            foreach (var mode in Enum.GetValues(typeof(DrawCameraMode)))
            {
                if (SceneRenderModeWindow.DrawCameraModeExists((DrawCameraMode)mode) && cameraMode == GetBuiltinCameraMode((DrawCameraMode)mode))
                {
                    return true;
                }
            }

View on GitHub (pinned to 225b0fbdb5)

Solutions

1. Provide a non-empty, non-null name string.
2. Validate the name with string.IsNullOrEmpty before calling AddCameraMode.
3. Use a sensible default name if the source value is empty.

Example fix

// before
SceneView.AddCameraMode(modeName, "Custom");

// after
string name = string.IsNullOrEmpty(modeName) ? "UnnamedMode" : modeName;
SceneView.AddCameraMode(name, "Custom");

bool IsValidModeName(string name)
{
    return !string.IsNullOrEmpty(name);
}

When it happens

Trigger: Calling SceneView.AddCameraMode with an empty string or null for name. Programmatic mode creation where the name is derived from user input or config that can be empty.

Common situations: Editor extension that registers custom draw modes based on configurable names. Data-driven mode registration where a config entry is missing the name field.

Related errors

• Use cameraMode to set user-defined modes
• The provided camera mode {0} is not registered!
• A mode named {0} already exists in section {1}
• Attempting to set an incorrect number of icons for {namedBui
• The setting label can't be null or empty.

AI-assisted analysis of Unity-Technologies/UnityCsReference@225b0fbdb5 (2026-08-13). Data as JSON: /api/errors/5a277695325171f9. Report an issue: GitHub.