avalonia-layout-and-virtualization

name	avalonia-layout-and-virtualization
description	Design or optimize Avalonia panels, measure and arrange behavior, custom layout controls, item virtualization, recycling, and large-data presentation. Use for `MeasureOverride` or `ArrangeOverride` work, invalidation bugs, virtualized item surfaces, or custom panel authoring.

Avalonia Layout and Virtualization

Start with:

• ../../references/30-layout-measure-arrange-and-custom-layout-controls.md
• ../../references/21-custom-layout-authoring.md
• ../../references/20-itemscontrol-virtualization-and-recycling.md

Load these when scrolling or templates are involved:

• ../../references/57-scrollviewer-offset-anchoring-and-snap-points.md
• ../../references/38-data-templates-and-idatatemplate-selector-patterns.md

Workflow

1. Define layout contract first: desired size, final arrangement, invalidation rules.
2. Use built-in panels and recycling paths before creating a custom panel.
3. Verify how virtualization, scrolling, and templates interact on large data sets.
4. Measure before and after changes when performance is the reason for the work.

Rules

• Use InvalidateMeasure and InvalidateArrange deliberately.
• Avoid per-item heavy logic inside measuring and arranging hot paths.
• Keep virtualization-friendly templates light and deterministic.