[Issue-Resolver] Fix #32903 - Sliderbinding initialization order issue

src/Controls/src/Core/Slider/Slider.cs

@@ -11,19 +11,19 @@ namespace Microsoft.Maui.Controls
 	public partial class Slider : View, ISliderController, IElementConfiguration<Slider>, ISlider
 	{
 		/// <summary>Bindable property for <see cref="Minimum"/>.</summary>
-		public static readonly BindableProperty MinimumProperty = BindableProperty.Create(nameof(Minimum), typeof(double), typeof(Slider), 0d, coerceValue: (bindable, value) =>
+		public static readonly BindableProperty MinimumProperty = BindableProperty.Create(nameof(Minimum), typeof(double), typeof(Slider), 0d, propertyChanged: (bindable, oldValue, newValue) =>
 		{
 			var slider = (Slider)bindable;
-			slider.Value = slider.Value.Clamp((double)value, slider.Maximum);
-			return value;
+			// Re-coerce Value to ensure it stays within valid range
+			slider.Value = slider.Value.Clamp((double)newValue, slider.Maximum);
 		});
 
 		/// <summary>Bindable property for <see cref="Maximum"/>.</summary>
-		public static readonly BindableProperty MaximumProperty = BindableProperty.Create(nameof(Maximum), typeof(double), typeof(Slider), 1d, coerceValue: (bindable, value) =>
+		public static readonly BindableProperty MaximumProperty = BindableProperty.Create(nameof(Maximum), typeof(double), typeof(Slider), 1d, propertyChanged: (bindable, oldValue, newValue) =>
 		{
 			var slider = (Slider)bindable;
-			slider.Value = slider.Value.Clamp(slider.Minimum, (double)value);
-			return value;
+			// Re-coerce Value to ensure it stays within valid range
+			slider.Value = slider.Value.Clamp(slider.Minimum, (double)newValue);
 		});
 
 		/// <summary>Bindable property for <see cref="Value"/>.</summary>

src/Controls/tests/TestCases.HostApp/Issues/Issue32903.xaml

@@ -0,0 +1,53 @@
+<?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.Issue32903"
+             Title="Issue 32903">
+    <VerticalStackLayout Padding="20" Spacing="10">
+        <Label Text="Slider Binding Initialization Order Test"
+               FontSize="18"
+               FontAttributes="Bold"
+               HorizontalOptions="Center"
+               Margin="0,0,0,20"/>
+
+        <Label Text="Expected: Value should be 50 (not 10)"
+               FontSize="14"
+               Margin="0,0,0,10"/>
+
+        <Label x:Name="ValueLabel"
+               AutomationId="ValueLabel"
+               Text="{Binding Value, StringFormat='Current Value: {0:F0}'}"
+               FontSize="16"
+               HorizontalOptions="Center"
+               Margin="0,0,0,10"/>
+
+        <Label Text="{Binding ValueMin, StringFormat='Minimum: {0:F0}'}"
+               FontSize="14"
+               HorizontalOptions="Center"/>
+
+        <Label Text="{Binding ValueMax, StringFormat='Maximum: {0:F0}'}"
+               FontSize="14"
+               HorizontalOptions="Center"/>
+
+        <Slider x:Name="TestSlider"
+                AutomationId="TestSlider"
+                Minimum="{Binding ValueMin}"
+                Maximum="{Binding ValueMax}"
+                Value="{Binding Value, Mode=TwoWay}"
+                Margin="0,20,0,0"/>
+
+        <Label x:Name="ActualValueLabel"
+               AutomationId="ActualValueLabel"
+               Text="{Binding Source={x:Reference TestSlider}, Path=Value, StringFormat='Slider.Value: {0:F0}'}"
+               FontSize="16"
+               HorizontalOptions="Center"
+               TextColor="Red"
+               Margin="0,10,0,0"/>
+
+        <Label Text="Bug: If Value shows 10 instead of 50, the binding order issue exists"
+               FontSize="12"
+               HorizontalOptions="Center"
+               TextColor="Gray"
+               Margin="0,10,0,0"/>
+    </VerticalStackLayout>
+</ContentPage>

src/Controls/tests/TestCases.HostApp/Issues/Issue32903.xaml.cs

@@ -0,0 +1,82 @@
+using System.ComponentModel;
+
+namespace Maui.Controls.Sample.Issues
+{
+	[Issue(IssueTracker.Github, 32903, "Slider Binding Initialization Order Causes Incorrect Value Assignment in XAML", PlatformAffected.All)]
+	public partial class Issue32903 : ContentPage
+	{
+		public Issue32903()
+		{
+			InitializeComponent();
+
+			var viewModel = new SliderViewModel();
+			BindingContext = viewModel;
+
+			// Log initial values for debugging
+			Console.WriteLine($"[Issue32903] ViewModel initialized - Min: {viewModel.ValueMin}, Max: {viewModel.ValueMax}, Value: {viewModel.Value}");
+
+			// Use Dispatcher to log actual slider values after bindings are applied
+			Dispatcher.DispatchDelayed(TimeSpan.FromMilliseconds(100), () =>
+			{
+				Console.WriteLine($"[Issue32903] After bindings - Slider.Minimum: {TestSlider.Minimum}, Slider.Maximum: {TestSlider.Maximum}, Slider.Value: {TestSlider.Value}");
+				Console.WriteLine($"[Issue32903] ViewModel.Value: {viewModel.Value}");
+			});
+		}
+	}
+
+	public class SliderViewModel : INotifyPropertyChanged
+	{
+		private double _valueMin = 10;
+		private double _valueMax = 100;
+		private double _value = 50;
+
+		public double ValueMin
+		{
+			get => _valueMin;
+			set
+			{
+				if (_valueMin != value)
+				{
+					_valueMin = value;
+					Console.WriteLine($"[SliderViewModel] ValueMin set to: {value}");
+					OnPropertyChanged(nameof(ValueMin));
+				}
+			}
+		}
+
+		public double ValueMax
+		{
+			get => _valueMax;
+			set
+			{
+				if (_valueMax != value)
+				{
+					_valueMax = value;
+					Console.WriteLine($"[SliderViewModel] ValueMax set to: {value}");
+					OnPropertyChanged(nameof(ValueMax));
+				}
+			}
+		}
+
+		public double Value
+		{
+			get => _value;
+			set
+			{
+				if (_value != value)
+				{
+					Console.WriteLine($"[SliderViewModel] Value changing from {_value} to {value}");
+					_value = value;
+					OnPropertyChanged(nameof(Value));
+				}
+			}
+		}
+
+		public event PropertyChangedEventHandler PropertyChanged;
+
+		protected virtual void OnPropertyChanged(string propertyName)
+		{
+			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
+		}
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue32903.cs

@@ -0,0 +1,46 @@
+using System;
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue32903 : _IssuesUITest
+	{
+		public Issue32903(TestDevice device) : base(device) { }
+
+		public override string Issue => "Slider Binding Initialization Order Causes Incorrect Value Assignment in XAML";
+
+		[Test]
+		[Category(UITestCategories.Slider)]
+		public void SliderValueShouldInitializeCorrectlyWithBindings()
+		{
+			// Wait for the page to load
+			App.WaitForElement("ValueLabel");
+
+			// Get the actual slider value displayed
+			var actualValueText = App.FindElement("ActualValueLabel").GetText();
+
+			// The bug: Value should be 50, but due to binding order it becomes 10 (or 1)
+			// Extract the numeric value from "Slider.Value: X"
+			if (actualValueText == null)
+			{
+				Assert.Fail("ActualValueLabel text is null");
+				return;
+			}
+
+			var valueStr = actualValueText.Replace("Slider.Value:", string.Empty, StringComparison.Ordinal).Trim();
+			var actualValue = double.Parse(valueStr);
+
+			// The bug manifests as Value being clamped to Minimum (10) or default Maximum (1)
+			// Expected: 50
+			// Actual (with bug): 10 or 1
+			Console.WriteLine($"[Test] Slider.Value is: {actualValue}");
+
+			// This test will FAIL with the bug (Value will be 10 or 1 instead of 50)
+			// After the fix, this test should PASS (Value will be 50)
+			Assert.That(actualValue, Is.EqualTo(50).Within(0.1), 
+				$"Slider Value should initialize to 50, but was {actualValue}. This indicates the binding initialization order bug.");
+		}
+	}
+}