[Android] Fixed Setting a Label visible after having had focus on a InputView will increase the Label's height

src/Controls/tests/TestCases.HostApp/Issues/Issue29194.cs

@@ -0,0 +1,37 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 29194, "[Android][Label] Setting a Label visible after having had focus on a InputView will increase the Label's height", PlatformAffected.Android)]
+public class Issue29194 : ContentPage
+{
+    public Issue29194()
+    {
+        var mySwitch = new Switch() { AutomationId = "Switch" };
+
+        var label = new Label
+        {
+            Text = "Hello, World!",
+            BackgroundColor = Colors.Red,
+            AutomationId = "Label"
+        };
+
+        label.SetBinding(Label.IsVisibleProperty, new Binding(nameof(Switch.IsToggled), source: mySwitch));
+
+        var verticalStack = new VerticalStackLayout
+        {
+            Children =
+            {
+                label,
+                mySwitch,
+                new UITestEntry() {AutomationId = "Entry",IsCursorVisible=false},
+            }
+        };
+
+        var scrollView = new ScrollView
+        {
+            Content = verticalStack
+        };
+
+        Content = scrollView;
+
+    }
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue29194.cs

@@ -0,0 +1,23 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+public class Issue29194 : _IssuesUITest
+{
+    public Issue29194(TestDevice device) : base(device) { }
+
+    public override string Issue => "[Android][Label] Setting a Label visible after having had focus on a InputView will increase the Label's height";
+
+    [Test]
+    [Category(UITestCategories.Label)]
+    public void LabelShouldSizeProperly()
+    {
+        App.WaitForElement("Entry");
+        App.Tap("Entry");
+        App.Tap("Switch");
+        App.WaitForElement("Label");
+        App.DismissKeyboard();
+        VerifyScreenshot();
+    }
+}

src/Core/src/Platform/Android/MauiTextView.cs

@@ -22,8 +22,12 @@ protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
 		{
 			if (MeasureSpec.GetMode(widthMeasureSpec) == MeasureSpecMode.AtMost && Layout is not null)
 			{
-				int maxWidth = (int)Math.Ceiling(GetMaxLineWidth(Layout)) + CompoundPaddingLeft + CompoundPaddingRight;
-				widthMeasureSpec = MeasureSpec.MakeMeasureSpec(maxWidth, MeasureSpecMode.AtMost);
+				// Ensure the Layout is valid and measured before reading LineCount or GetLineWidth(i) to avoid unnecessary calculations.
+				if (Layout.Width > 0)
+				{
+					int maxWidth = (int)Math.Ceiling(GetMaxLineWidth(Layout)) + CompoundPaddingLeft + CompoundPaddingRight;
+					widthMeasureSpec = MeasureSpec.MakeMeasureSpec(maxWidth, MeasureSpecMode.AtMost);
+				}
 			}
 			base.OnMeasure(widthMeasureSpec, heightMeasureSpec);
 		}