NavBarTitleTestPage.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Xamarin.Forms.Controls
{
	public class NavBarTitleTestPage : ContentPage
	{

		public NavBarTitleTestPage()
		{
			var navTab = new NavigationPage { Title = "Hello 1 nav" };
			navTab.PushAsync(GetPage(navTab));

			var stackPages = new StackLayout();

			var btn3 = new Button
			{
				Text = "tab",
				Command = new Command(async () =>
				{
					var tabbed = new TabbedPage { Title = "Main Tab" };
					tabbed.Children.Add(navTab);
					tabbed.Children.Add(GetPage(navTab));
					await Navigation.PushModalAsync(tabbed);
				})
			};

			var btn4 = new Button
			{
				Text = "mdp",
				Command = new Command(async () =>
				{
					var newNav = new NavigationPage { Title = "Hello 1 nav", BarBackgroundColor = Color.Pink, BarTextColor = Color.Blue };
					var mdp = new FlyoutPage();
					await newNav.PushAsync(GetPage(newNav));
					mdp.Flyout = new ContentPage
					{
						Title = "Flyout",
						BackgroundColor = Color.Red,
						Content = new Button
						{
							Text = "new",
							Command = new Command(() =>
							{
								mdp.Detail = new ContactsPage { Title = "hello 3" };
								mdp.IsPresented = false;
							})
						}
					};
					mdp.Detail = newNav;
					await Navigation.PushModalAsync(mdp);
				})
			};

			var btn5 = new Button
			{
				Text = "nav",
				Command = new Command(async () =>
				{
					var newNav = new NavigationPage { Title = "Hello 1 nav" };
					await newNav.PushAsync(GetPage(newNav));
					await Navigation.PushModalAsync(newNav);
				})
			};

			var btn6 = new Button
			{
				Text = "change nav",
				Command = new Command(() =>
				{
					(Parent as NavigationPage).BarBackgroundColor = Color.Blue;
					(Parent as NavigationPage).BarTextColor = Color.Pink;
				})
			};

			stackPages.Children.Add(btn3);
			stackPages.Children.Add(btn4);
			stackPages.Children.Add(btn5);
			stackPages.Children.Add(btn6);
			Content = stackPages;
		}

		static Page GetPage(NavigationPage navTab)
		{
			var stack = new StackLayout();
			var newPage = new ContentPage { Title = "Hello 2", Content = stack };
			var btn1 = new Button { Text = "next", Command = new Command(async () => await newPage.Navigation.PushAsync(new ContactsPage { Title = "hello 3" })) };
			var btn2 = new Button
			{
				Text = "change nav",
				Command = new Command(() =>
				{
					navTab.BarBackgroundColor = Color.Blue;
					navTab.BarTextColor = Color.Pink;
				})
			};
			var btn3 = new Button
			{
				Text = "pop modal",
				Command = new Command(() =>
				{
					newPage.Navigation.PopModalAsync();
				})
			};
			stack.Children.Add(btn1);
			stack.Children.Add(btn2);
			stack.Children.Add(btn3);
			return newPage;

		}
	}
}