Align OnDoubleTap behavior on Windows and Android

src/Controls/src/Core/Platform/Android/InnerGestureListener.cs

@@ -20,6 +20,7 @@ internal class InnerGestureListener : Object, GestureDetector.IOnGestureListener
 		float _lastX;
 		float _lastY;
 		bool _disposed;
+		bool _singleTapFiredInSequence;
 
 		Func<float, float, bool> _swipeDelegate;
 		Func<bool> _swipeCompletedDelegate;
@@ -79,6 +80,11 @@ bool GestureDetector.IOnDoubleTapListener.OnDoubleTap(MotionEvent e)
 
 			if (HasDoubleTapHandler())
 			{
+				// Reset the flag since this is completing a double tap sequence
+				_singleTapFiredInSequence = false;
+
+				// Fire only the double tap handler here Single tap was already
+				// fired earlier in OnSingleTapUp for better timing
 				return _tapDelegate(2, e);
 			}
 
@@ -151,8 +157,15 @@ bool GestureDetector.IOnGestureListener.OnSingleTapUp(MotionEvent e)
 
 			if (HasDoubleTapHandler())
 			{
-				// Because we have a handler for double-tap, we need to wait for
-				// OnSingleTapConfirmed (to verify it's really just a single tap) before running the delegate
+				// Fire single tap immediately for the first tap, even when we
+				// have double tap handlers (mimics Windows timing)
+				if (HasSingleTapHandler())
+				{
+					_tapDelegate(1, e);
+					_singleTapFiredInSequence = true; // Track that we fired single tap
+				}
+
+				// Still return false to continue waiting for potential double tap
 				return false;
 			}
 
@@ -178,8 +191,15 @@ bool GestureDetector.IOnDoubleTapListener.OnSingleTapConfirmed(MotionEvent e)
 				return false;
 			}
 
+			// Check if we already fired the single tap in OnSingleTapUp during a potential double tap sequence
+			if (_singleTapFiredInSequence)
+			{
+				_singleTapFiredInSequence = false; // Reset the flag
+				return false; // Don't fire again
+			}
+
 			// Since there was a double-tap handler, we had to wait for OnSingleTapConfirmed;
-			// Now that we're sure it's a single tap, we can run the delegate
+			// This is called only for confirmed single taps (not part of double tap sequences)
 			return _tapDelegate(1, e);
 		}
 

src/Controls/src/Core/Platform/GestureManager/GesturePlatformManager.Windows.cs

@@ -797,12 +797,30 @@ bool ProcessGestureRecognizers(IEnumerable<TapGestureRecognizer>? tapGestures)
 					return handled;
 				}
 
+				bool onlyDoubleTaps = false;
+
+				if (e is DoubleTappedRoutedEventArgs)
+				{
+					// Is there a recognizer that has exactly two taps?
+					foreach (var recognizer in tapGestures)
+					{
+						if (recognizer.NumberOfTapsRequired == 2)
+						{
+							onlyDoubleTaps = true;
+							break;
+						}
+					}
+				}
+
 				foreach (var recognizer in tapGestures)
 				{
-					recognizer.SendTapped(view, (relativeTo) => GetPosition(relativeTo, e));
+					if (!onlyDoubleTaps || recognizer.NumberOfTapsRequired == 2)
+					{
+						recognizer.SendTapped(view, (relativeTo) => GetPosition(relativeTo, e));
 
-					e.SetHandled(true);
-					handled = true;
+						e.SetHandled(true);
+						handled = true;
+					}
 				}
 
 				return handled;
@@ -827,7 +845,9 @@ bool ValidateGesture(TapGestureRecognizer g)
 					return false;
 
 				if (e is DoubleTappedRoutedEventArgs)
+				{
 					return g.NumberOfTapsRequired == 1 || g.NumberOfTapsRequired == 2;
+				}
 
 				return g.NumberOfTapsRequired == 1;
 			}

src/Controls/src/Core/Platform/GestureManager/GesturePlatformManager.iOS.cs

@@ -664,6 +664,7 @@ _handler.VirtualView is View v &&
 					{
 						_proxy ??= new ShouldReceiveTouchProxy(this);
 						nativeRecognizer.ShouldReceiveTouch = _proxy.ShouldReceiveTouch;
+
 						PlatformView.AddGestureRecognizer(nativeRecognizer);
 
 					}

src/Controls/tests/TestCases.HostApp/Issues/Issue20870.xaml

@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<ContentPage xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+             x:Class="Maui.Controls.Sample.Issues.Issue20870"
+             xmlns:local="clr-namespace:Maui.Controls.Sample.Issues"
+             Title="Issue20870">
+    <Grid>
+        <Grid.RowDefinitions>
+            <RowDefinition Height="Auto"/>
+            <RowDefinition Height="*"/>
+        </Grid.RowDefinitions>
+
+    <FlexLayout Grid.Row="0" Direction="Row" Wrap="Wrap" JustifyContent="SpaceAround" AlignItems="Center" Margin="10" MinimumHeightRequest="80">
+            <!-- Using Labels instead of Buttons for gesture tests to avoid platform-specific container wrapping (iOS/macOS) affecting double-tap routing. -->
+            <Label x:Name="ButtonSingleTap" AutomationId="ButtonSingleTap" Text="SingleTap" FontSize="20" TextColor="Red" VerticalOptions="Center">
+                <Label.GestureRecognizers>
+                    <TapGestureRecognizer Tapped="OnTap"/>
+                </Label.GestureRecognizers>
+            </Label>
+            <Label x:Name="ButtonDoubleTap" AutomationId="ButtonDoubleTap" Text="DoubleTap" FontSize="20" TextColor="Green" VerticalOptions="Center">
+                <Label.GestureRecognizers>
+                    <TapGestureRecognizer Tapped="OnDoubleTap" NumberOfTapsRequired="2"/>
+                </Label.GestureRecognizers>
+            </Label>
+            <Label x:Name="ButtonSingleAndDoubleTap" AutomationId="ButtonSingleAndDoubleTap" Text="SingleAndDoubleTap" FontSize="20" TextColor="Blue" VerticalOptions="Center">
+                <Label.GestureRecognizers>
+                    <TapGestureRecognizer Tapped="OnTap"/>
+                    <TapGestureRecognizer Tapped="OnDoubleTap" NumberOfTapsRequired="2"/>
+                </Label.GestureRecognizers>
+            </Label>
+            <Label x:Name="ButtonDoubleAndSingleTap" AutomationId="ButtonDoubleAndSingleTap" Text="DoubleAndSingleTap" FontSize="20" TextColor="Purple" VerticalOptions="Center">
+                <Label.GestureRecognizers>
+                    <TapGestureRecognizer Tapped="OnDoubleTap" NumberOfTapsRequired="2"/>
+                    <TapGestureRecognizer Tapped="OnTap"/>
+                </Label.GestureRecognizers>
+            </Label>
+            <Label x:Name="Clear" AutomationId="Clear" Text="Clear" FontSize="20" TextColor="Black" VerticalOptions="Center">
+                <Label.GestureRecognizers>
+                    <TapGestureRecognizer Tapped="Clear_Tapped" />
+                </Label.GestureRecognizers>
+            </Label>
+        </FlexLayout>
+
+        <ScrollView Grid.Row="1">
+            <Editor x:Name="Results" AutomationId="Results" Margin="20"/>
+        </ScrollView>
+    </Grid>
+</ContentPage>

src/Controls/tests/TestCases.HostApp/Issues/Issue20870.xaml.cs

@@ -0,0 +1,40 @@
+#nullable enable
+using Microsoft.Maui.Controls;
+using Microsoft.Maui.Controls.Xaml;
+
+namespace Maui.Controls.Sample.Issues;
+
+[XamlCompilation(XamlCompilationOptions.Compile)]
+[Issue(IssueTracker.Github, 20870, "Single-tap and double-tap tests", PlatformAffected.All)]
+
+public partial class Issue20870 : ContentPage
+{
+	public Issue20870()
+	{
+		InitializeComponent();
+		BindingContext = this;
+	}
+
+	// NOTE: Using Labels for gesture recognizer tests (instead of Buttons) to avoid
+	// platform-specific wrapper/container views on iOS/macOS that can interfere with
+	// hit testing and double-tap routing. This keeps gesture routing consistent across
+	// platforms for the purpose of these cross-platform UITests.
+	private void Clear_Tapped(object? sender, TappedEventArgs e)
+	{
+		Results.Text = string.Empty;
+	}
+
+	private void OnTap(object? sender, TappedEventArgs e)
+	{
+		string text = Results.Text;
+		string delimiter = string.IsNullOrEmpty(text) ? "" : "|";
+		Results.Text = $"{text}{delimiter}OnTap called";
+	}
+
+	private void OnDoubleTap(object? sender, TappedEventArgs e)
+	{
+		string text = Results.Text;
+		string delimiter = string.IsNullOrEmpty(text) ? "" : "|";
+		Results.Text = $"{text}{delimiter}OnDoubleTap called";
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue20870.cs

@@ -0,0 +1,61 @@
+using NUnit.Framework;
+using NUnit.Framework.Legacy;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue20870 : _IssuesUITest
+{
+	public Issue20870(TestDevice device) : base(device) { }
+
+	public override string Issue => "Single-tap and double-tap tests";
+
+	[Test]
+	[Category(UITestCategories.Gestures)]
+	public async Task TapsAndDoubleTaps()
+	{
+		// Initialize.
+		App.WaitForElement("Results");
+
+		// Verify a button with a single-tap gesture recognizer.
+		App.Tap("ButtonSingleTap");
+		await Task.Delay(200); // Do not artificially simulate a double-tap.
+		App.Tap("ButtonSingleTap");
+
+		await Task.Delay(1000);
+
+		string? text = App.FindElement("Results").GetText()?.Trim();
+		ClassicAssert.AreEqual("OnTap called|OnTap called", text);
+
+		App.Tap("Clear");
+
+		// Verify a button with a double-tap gesture recognizer.
+		App.Tap("ButtonDoubleTap");
+		await Task.Delay(200); // Do not artificially simulate a triple-tap.
+		App.DoubleTap("ButtonDoubleTap");
+
+		text = App.FindElement("Results").GetText()?.Trim();
+		ClassicAssert.AreEqual("OnDoubleTap called", text);
+
+		App.Tap("Clear");
+
+		// Verify a button with single-tap and double-tap gesture recognizers. Note the order of recognizer registrations.
+		App.Tap("ButtonSingleAndDoubleTap");
+		await Task.Delay(200);
+		App.DoubleTap("ButtonSingleAndDoubleTap");
+
+		text = App.FindElement("Results").GetText()?.Trim();
+		ClassicAssert.AreEqual("OnTap called|OnTap called|OnDoubleTap called", text);
+
+		App.Tap("Clear");
+
+		// Verify a button with double-tap and single-tap gesture recognizers. Note the order of recognizer registrations.
+		App.Tap("ButtonDoubleAndSingleTap");
+		await Task.Delay(200);
+		App.DoubleTap("ButtonDoubleAndSingleTap");
+
+		text = App.FindElement("Results").GetText()?.Trim();
+		ClassicAssert.AreEqual("OnTap called|OnTap called|OnDoubleTap called", text);
+	}
+}