AvaloniaUI/Avalonia · error · ArgumentException

Attempt to call InvalidateMeasure on wrong LayoutManager.

Error message

Attempt to call InvalidateMeasure on wrong LayoutManager.

What it means

InvalidateMeasure throws when a control whose layout root does not match the LayoutManager's owner is passed for invalidation. Each LayoutManager is scoped to one layout root; calling it on a control that belongs to a different visual tree root indicates a cross-tree misuse of the layout invalidation API. The guard fires after confirming the control IS attached to a visual tree, but is rooted elsewhere.

Source

Thrown at src/Avalonia.Base/Layout/LayoutManager.cs:68

            if (_disposed)
            {
                return;
            }

            if (!control.IsAttachedToVisualTree)
            {
#if DEBUG
                throw new AvaloniaInternalException(
                    "LayoutManager.InvalidateMeasure called on a control that is detached from the visual tree.");
#else
                return;
#endif
            }

            if (control.GetLayoutRoot() != _owner)
            {
                throw new ArgumentException("Attempt to call InvalidateMeasure on wrong LayoutManager.");
            }

            _toMeasure.Enqueue(control);
            QueueLayoutPass();
        }

        /// <inheritdoc/>
        public virtual void InvalidateArrange(Layoutable control)
        {
            control = control ?? throw new ArgumentNullException(nameof(control));
            Dispatcher.UIThread.VerifyAccess();

            if (_disposed)
            {
                return;
            }

            if (!control.IsAttachedToVisualTree)

View on GitHub (pinned to 11c5427268)

Solutions

1. Use the control's own layout root manager — call control.GetLayoutRoot().LayoutManager or let the control invalidate itself via its Layoutable.InvalidateMeasure() method.
2. Ensure the control is properly removed from its old visual tree before adding it to a new one.
3. Avoid caching LayoutManager references across reparenting operations.

Example fix

// before
_someSharedLayoutManager.InvalidateMeasure(myControl);

// after
myControl.InvalidateMeasure(); // routes through the correct manager automatically

// Always invalidate through the control itself rather than a cached manager
// control.InvalidateMeasure() routes to the correct manager automatically.
// If you must use a manager directly, verify ownership:
if (control.GetLayoutRoot() == layoutManagerOwner)
    layoutManager.InvalidateMeasure(control);

When it happens

Trigger: Calling layoutManager.InvalidateMeasure(control) where control.GetLayoutRoot() != layoutManager._owner. Can happen when a control is reparented between windows, or when a shared/global LayoutManager reference is used instead of the control's own layout root's manager.

Common situations: Reparenting a control between different top-level windows without going through proper removal/add. Holding a stale LayoutManager reference after the control moved. A control moved to a popup or overlay with its own layout root while a previous manager still tries to invalidate it.

Related errors

• Attempt to call InvalidateArrange on wrong LayoutManager.
• Transition elements have different parents.
• Controls for PageSlide must have same parent.
• Cannot determine visual parent.
• The control isn't currently attached to a toplevel

AI-assisted analysis of AvaloniaUI/Avalonia@11c5427268 (2026-08-13). Data as JSON: /api/errors/86159067bd13f317. Report an issue: GitHub.