fix(responsive): layout breakpoint calculation

unoplatform · Dec 14, 2023 · 3690ecc · 3690ecc
1 parent 775b466
commit 3690ecc
Showing 1 changed file with 21 additions and 6 deletions.
diff --git a/src/Uno.Toolkit.UI/Helpers/ResponsiveHelper.cs b/src/Uno.Toolkit.UI/Helpers/ResponsiveHelper.cs
@@ -9,6 +9,8 @@
 
 #if IS_WINUI
 using Microsoft.UI.Xaml;
+using System.Linq;
+
 #else
 using Windows.UI.Xaml;
 using Windows.UI.Core;
@@ -191,21 +193,34 @@ internal void Register(IResponsiveCallback host)
 	internal (ResponsiveLayout Layout, Size Size, Layout? Result) ResolveLayout(ResponsiveLayout? layout, IEnumerable<Layout> options)
 	{
 		layout ??= Layout;
-		var result =
-			options.FirstOrNull(SatisfyLayoutThreshold) ??
-			options.LastOrNull();
+		var result = ResolveLayoutCore(layout, WindowSize.Width, options);
 
 		return (layout, WindowSize, result);
+	}
 
-		bool SatisfyLayoutThreshold(Layout x) => x switch
+	internal static Layout? ResolveLayoutCore(ResponsiveLayout layout, double width, IEnumerable<Layout> options)
+	{
+		return options.Append((Layout)int.MaxValue)
+			.ZipSkipOne()
+			.Select(x => new
+			{
+				Layout = x.Previous,
+				InclusiveLBound = GetThreshold(x.Previous),
+				ExclusiveUBound = GetThreshold(x.Current),
+			})
+			.FirstOrDefault(x => x.InclusiveLBound <= width && width < x.ExclusiveUBound)
+			?.Layout ?? options.FirstOrNull();
+
+		double GetThreshold(Layout x) => x switch
 		{
 			UI.Layout.Narrowest => layout.Narrowest,
 			UI.Layout.Narrow => layout.Narrow,
 			UI.Layout.Normal => layout.Normal,
 			UI.Layout.Wide => layout.Wide,
 			UI.Layout.Widest => layout.Widest,
-			_ => double.NaN,
-		} >= WindowSize.Width;
+
+			_ => double.PositiveInfinity,
+		};
 	}
 
 	internal static IDisposable UsingDebuggableInstance()