[Android] Fix bottom safe area padding dropping to zero when keyboard is shown

src/Controls/tests/TestCases.HostApp/Issues/Issue32871.cs

@@ -0,0 +1,141 @@
+#if ANDROID
+using Android.Views;
+using AView = Android.Views.View;
+#endif
+
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 32871, "[Android] Bottom insets issues when keyboard is shown", PlatformAffected.Android)]
+public partial class Issue32871 : ContentPage
+{
+	public Issue32871()
+	{
+		SafeAreaEdges = SafeAreaEdges.None;
+		BackgroundColor = Colors.Green;
+
+		var paddingLabel = new Label
+		{
+			Text = "waiting",
+			AutomationId = "PaddingLabel",
+			TextColor = Colors.White,
+			FontSize = 12
+		};
+
+		var entry = new Entry
+		{
+			Placeholder = "Tap here to show keyboard",
+			AutomationId = "TestEntry",
+			VerticalOptions = LayoutOptions.Start,
+			HorizontalOptions = LayoutOptions.Fill,
+			HeightRequest = 56
+		};
+
+		var grid = new Grid
+		{
+			AutomationId = "MainGrid",
+			SafeAreaEdges = SafeAreaEdges.Default,
+			BackgroundColor = Colors.Red,
+			RowDefinitions =
+			{
+				new RowDefinition(80),
+				new RowDefinition(GridLength.Auto),
+				new RowDefinition(GridLength.Star),
+				new RowDefinition(GridLength.Auto)
+			}
+		};
+
+		var label = new Label
+		{
+			Text = "Issue 32871",
+			AutomationId = "HeaderLabel",
+			HorizontalTextAlignment = Microsoft.Maui.TextAlignment.Center,
+			VerticalOptions = LayoutOptions.Start,
+			TextColor = Colors.White
+		};
+
+		var bottomButton = new Button
+		{
+			Text = "Bottom Button",
+			AutomationId = "BottomButton",
+			BackgroundColor = Colors.Blue,
+			TextColor = Colors.White
+		};
+
+		Grid.SetRow(label, 0);
+		Grid.SetRow(paddingLabel, 1);
+		Grid.SetRow(entry, 2);
+		Grid.SetRow(bottomButton, 3);
+
+		grid.Children.Add(label);
+		grid.Children.Add(paddingLabel);
+		grid.Children.Add(entry);
+		grid.Children.Add(bottomButton);
+
+		Content = grid;
+
+		SetupPlatform(grid, paddingLabel);
+	}
+
+	partial void SetupPlatform(Grid grid, Label paddingLabel);
+
+	protected override void OnDisappearing()
+	{
+		base.OnDisappearing();
+		CleanupPlatform();
+	}
+
+	partial void CleanupPlatform();
+}
+
+#if ANDROID
+public partial class Issue32871
+{
+	SoftInput _previousSoftInputMode;
+
+	partial void SetupPlatform(Grid grid, Label paddingLabel)
+	{
+		var window = Microsoft.Maui.ApplicationModel.Platform.CurrentActivity?.Window;
+		if (window?.Attributes is WindowManagerLayoutParams attr)
+		{
+			_previousSoftInputMode = attr.SoftInputMode;
+		}
+		window?.SetSoftInputMode(SoftInput.AdjustUnspecified | SoftInput.StateHidden);
+
+		grid.HandlerChanged += (s, e) =>
+		{
+			if (grid.Handler?.PlatformView is AView nativeView)
+			{
+				paddingLabel.Text = $"NativePadding: B={nativeView.PaddingBottom}";
+				nativeView.AddOnLayoutChangeListener(new LayoutListener(nativeView, paddingLabel));
+			}
+		};
+	}
+
+	partial void CleanupPlatform()
+	{
+		var window = Microsoft.Maui.ApplicationModel.Platform.CurrentActivity?.Window;
+		window?.SetSoftInputMode(_previousSoftInputMode);
+	}
+
+	class LayoutListener : Java.Lang.Object, AView.IOnLayoutChangeListener
+	{
+		readonly WeakReference<AView> _view;
+		readonly WeakReference<Label> _label;
+
+		public LayoutListener(AView view, Label label)
+		{
+			_view = new WeakReference<AView>(view);
+			_label = new WeakReference<Label>(label);
+		}
+
+		public void OnLayoutChange(AView v, int left, int top, int right, int bottom,
+			int oldLeft, int oldTop, int oldRight, int oldBottom)
+		{
+			if (_view.TryGetTarget(out var view) && _label.TryGetTarget(out var label))
+			{
+				label.Text = $"NativePadding: B={view.PaddingBottom}";
+			}
+		}
+	}
+}
+#endif

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue32871.cs

@@ -0,0 +1,58 @@
+#if ANDROID // Android-only: fix and native padding assertion rely on Android platform code
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue32871 : _IssuesUITest
+{
+	public override string Issue => "[Android] Bottom insets issues when keyboard is shown";
+
+	public Issue32871(TestDevice device) : base(device)
+	{
+	}
+
+	[Test]
+	[Category(UITestCategories.SafeAreaEdges)]
+	public void BottomPaddingShouldBePreservedWhileKeyboardIsShowing()
+	{
+		App.WaitForElement("MainGrid");
+		App.WaitForTextToBePresentInElement("PaddingLabel", "NativePadding");
+
+		var initialPaddingText = App.FindElement("PaddingLabel").GetText() ?? "";
+		var initialBottomPadding = ExtractBottomPadding(initialPaddingText);
+
+		if (initialBottomPadding <= 0)
+		{
+			Assert.Ignore("Device has no navigation bar bottom inset — cannot validate this regression.");
+			return;
+		}
+
+		App.Tap("TestEntry");
+
+		Assert.That(App.WaitForKeyboardToShow(), Is.True,
+			"Keyboard must be visible to validate the fix.");
+
+		var paddingWhileKeyboard = App.FindElement("PaddingLabel").GetText() ?? "";
+		var bottomPaddingDuringKeyboard = ExtractBottomPadding(paddingWhileKeyboard);
+
+		Assert.That(bottomPaddingDuringKeyboard, Is.EqualTo(initialBottomPadding),
+			$"Bottom padding should be preserved while keyboard is showing. " +
+			$"Initial: {initialBottomPadding}px, During keyboard: {bottomPaddingDuringKeyboard}px.");
+	}
+
+	static double ExtractBottomPadding(string paddingText)
+	{
+		var prefix = "B=";
+		var idx = paddingText.IndexOf(prefix, StringComparison.Ordinal);
+		if (idx >= 0)
+		{
+			var valueStr = paddingText.Substring(idx + prefix.Length).Trim();
+			if (double.TryParse(valueStr, out var value))
+				return value;
+		}
+		return -1;
+	}
+}
+#endif

src/Core/src/Platform/Android/SafeAreaExtensions.cs

@@ -327,10 +327,6 @@ internal static double GetSafeAreaForEdge(SafeAreaRegions safeAreaRegion, double
 				// Return keyboard insets for any region that includes SoftInput
 				if (SafeAreaEdges.IsSoftInput(safeAreaRegion))
 					return keyBoardInsets.Bottom;
-
-				// if the keyboard is showing then we will just return 0 for the bottom inset
-				// because that part of the view is covered by the keyboard so we don't want to pad the view
-				return 0;
 			}
 		}