maui-linux/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla37462.cs

using System.Collections.Generic;
using System.Linq;
using Xamarin.Forms.CustomAttributes;
using Xamarin.Forms.Internals;

#if UITEST
using Xamarin.UITest;
using NUnit.Framework;
#endif


namespace Xamarin.Forms.Controls
{
	[Preserve (AllMembers = true)]
	[Issue (IssueTracker.Bugzilla, 37462, "Using App Compat/App Compat theme breaks Navigation.RemovePage on Android ",PlatformAffected.Android )]
	public class Bugzilla37462 : TestNavigationPage
	{
		protected override void Init ()
		{
			var page1 = new ContentPage { Title = "Page 1" };
			var button1 = new Button { Text = "Go To 2" };
			var label1 = new Label { Text = "This is a label on page 1" };
			page1.Content = new StackLayout { Children = { button1, label1 } };
			page1.Appearing += (sender, args) => {
				((IVisualElementController)page1).InvalidateMeasure(InvalidationTrigger.MeasureChanged);
			};

			var page2 = new ContentPage { Title = "Page 2" };
			var button2 = new Button { Text = "Go To 3" };
			var label2 = new Label { Text = "This is a label on page 2" };
			page2.Content = new StackLayout { Children = { button2, label2 } };

			var page3 = new ContentPage { Title = "Page 3" };
			var button3 = new Button { Text = "Go To 4" };
			var label3 = new Label { Text = "This is a label on page 3" };
			page3.Content = new StackLayout { Children = { button3, label3 } };

			var page4 = new ContentPage { Title = "Page 4" };
			var button4 = new Button { Text = "Back to 1" };
			var label4 = new Label { Text = "This is a label on page 4" };
			page4.Content = new StackLayout { Children = { button4, label4 } };

			button1.Clicked += async (sender, args) => { await Navigation.PushAsync (page2); };
			button2.Clicked += async (sender, args) => { await Navigation.PushAsync (page3); };
			button3.Clicked += async (sender, args) => { await Navigation.PushAsync (page4); };

			button4.Clicked += async (sender, args) => {
				List<Page> existingPages = Navigation.NavigationStack.ToList ();

				// Clear all pages except current and home
				foreach (Page page in existingPages) {
					if (page.Title != "Page 1" && page.Title != "Page 4") {
						Navigation.RemovePage (page);
					}
				}

				await Navigation.PopAsync ();
			};

			Navigation.PushAsync (page1);
		}

#if UITEST
		[Test]
		public void CanRemoveIntermediatePagesAndPopToFirstPage ()
		{
			// Start at page 1
			RunningApp.WaitForElement ("Go To 2");
			RunningApp.WaitForElement ("This is a label on page 1");
			RunningApp.Tap ("Go To 2");

			RunningApp.WaitForElement ("Go To 3");
			RunningApp.Tap ("Go To 3");

			RunningApp.WaitForElement ("Go To 4");
			RunningApp.Tap ("Go To 4");

			RunningApp.WaitForElement ("Back to 1");
			RunningApp.Tap ("Back to 1");

			// Clicking "Back to 1" should remove pages 2 and 3 from the stack
			// Then call PopAsync, which should return to page 1
			RunningApp.WaitForElement ("Go To 2");
			RunningApp.WaitForElement ("This is a label on page 1");
		}
#endif

	}
}