using Avalonia; using Avalonia.Controls; namespace Previewer { public class Center : Decorator { protected override Size ArrangeOverride(Size finalSize) { if (Child != null) { var desired = Child.DesiredSize; Child.Arrange(new Rect((finalSize.Width - desired.Width) / 2, (finalSize.Height - desired.Height) / 2, desired.Width, desired.Height)); } return finalSize; } } }