Enhanced Stepper to Support Dynamic Increment Mapping (dotnet#24396)

* Fix Stepper doesn't change increment value when being bound to a double in MVVM context (Windows)

* shipped file changes updated

* shipped file changes included

* changes added in unshipped file

* platform condition removed

* platform condition added in script file

* shipped file extra changes removed

* extra changes removed in unshipped.txt

* empty lines removed

* tizen shipped file changes reverted

* new test case and snapshot added for android & iOS

* WinUI snap added

* old changes reverted new changes added

* snap added for all platform

* Added AppendToMapping pattern

* Removed wrong namespace

* Renamed class name

* Updated testcase screenshot forMac

* Update StepperUITests.cs

* Revert "Update StepperUITests.cs"

This reverts commit 70ff4bc.

* Revert "Updated testcase screenshot forMac"

This reverts commit 0aadff6.

* Updated alignment in test case

* Updated MapInterval

* Updated test sample

* Reverted test images

* Revert "Reverted test images"

This reverts commit 0ecfc54.

* Removed test images

* Added test_fails_on_catalyst tag in test sample

---------

Co-authored-by: Dhivya-SF4094 <[email protected]>

src/Controls/src/Core/Hosting/AppHostBuilderExtensions.cs

@@ -257,6 +257,7 @@ internal static MauiAppBuilder RemapForControls(this MauiAppBuilder builder)
 		SwipeView.RemapForControls();
 		Picker.RemapForControls();
 		SearchBar.RemapForControls();
+		Stepper.RemapForControls();
 		TabbedPage.RemapForControls();
 		TimePicker.RemapForControls();
 		Layout.RemapForControls();

src/Controls/src/Core/Stepper/Stepper.Mapper.cs

@@ -0,0 +1,15 @@
+using System;
+
+namespace Microsoft.Maui.Controls;
+public partial class Stepper
+{
+    internal static new void RemapForControls()
+    {
+        StepperHandler.Mapper.AppendToMapping(nameof(Stepper.Increment), MapInterval);
+    }
+
+    internal static void MapInterval(IStepperHandler handler, IStepper stepper)
+    {
+        handler.UpdateValue(nameof(IStepper.Interval));
+    }
+}

src/Controls/tests/TestCases.HostApp/Issues/Issue20706.xaml

@@ -0,0 +1,23 @@
+<?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.Issue20706"
+             xmlns:local="clr-namespace:Maui.Controls.Sample.Issues">
+  <ContentPage.BindingContext>
+    <local:ViewModelClass/>
+  </ContentPage.BindingContext>
+  <ContentPage.Content>
+    <VerticalStackLayout>
+      <Stepper AutomationId="myStepper"
+               x:Name="stepperValue"
+               Maximum="1000"
+               Increment="{Binding Increment}"/>
+      <Entry AutomationId="entry"
+             Text="{Binding Value,Source={x:Reference stepperValue}} "/>
+      <Button AutomationId="incrementButton"
+              Text="Change Increment Value"
+              x:Name="button"
+              Clicked="button_Clicked"/>
+    </VerticalStackLayout>
+  </ContentPage.Content>
+</ContentPage>

src/Controls/tests/TestCases.HostApp/Issues/Issue20706.xaml.cs

@@ -0,0 +1,51 @@
+using System.ComponentModel;
+
+namespace Maui.Controls.Sample.Issues
+{
+	[Issue(IssueTracker.Github, 20706, "Stepper doesn't change increment value when being bound to a double in MVVM context (Windows)", PlatformAffected.UWP)]
+	public partial class Issue20706 : ContentPage
+	{
+		public Issue20706()
+		{
+			InitializeComponent();
+		}
+
+		private void button_Clicked(object sender, EventArgs e)
+		{
+			stepperValue.Increment = 10;
+		}
+	}
+
+	internal class ViewModelClass : INotifyPropertyChanged
+	{
+		private double _increment;
+
+		public double Increment
+		{
+			get
+			{
+				return _increment;
+			}
+
+			set
+			{
+				_increment = value;
+				OnPropertyChanged("Increment");
+			}
+		}
+
+		public ViewModelClass()
+		{
+			Increment = 2;
+		}
+		private void OnPropertyChanged(string v)
+		{
+			if (PropertyChanged != null)
+			{
+				PropertyChanged(this, new PropertyChangedEventArgs(v));
+			}
+		}
+
+		public event PropertyChangedEventHandler PropertyChanged;
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue20706.cs

@@ -0,0 +1,49 @@
+#if TEST_FAILS_ON_CATALYST // Stepper interaction is not implemented for catalyst
+using NUnit.Framework;
+using NUnit.Framework.Legacy;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue20706 : _IssuesUITest
+	{
+		public override string Issue => "Stepper doesn't change increment value when being bound to a double in MVVM context (Windows)";
+		public Issue20706(TestDevice device) : base(device)
+		{
+		}
+
+		[Test]
+		[Category(UITestCategories.Stepper)]
+		public void ChangeIncrementValue()
+		{
+			App.WaitForElement("entry");
+			// check the current value.
+			var initialValue = App.FindElement("entry").GetText();
+		    Assert.That("0", Is.EqualTo(initialValue));
+
+			// Increase the value.
+			App.IncreaseStepper("myStepper");
+
+			// Verify that the value has been increased.
+			var step1Value = App.FindElement("entry").GetText();
+			Assert.That("2", Is.EqualTo(step1Value));
+
+			// Change the Stepper increment value.
+			App.Click("incrementButton");
+
+			// Increase the value.
+			App.IncreaseStepper("myStepper");
+			var step2Value = App.FindElement("entry").GetText();
+			Assert.That("12", Is.EqualTo(step2Value));
+
+			// Decrease the value.
+			App.DecreaseStepper("myStepper");
+
+			// Verify that the value has decreased.
+			var step3Value = App.FindElement("entry").GetText();
+			Assert.That("2", Is.EqualTo(step3Value));
+		}
+	}
+}
+#endif