Databinding doesnt display anything - xamarin

Question

I am trying to print out observable collection into the listview.
It is for custom navigation. It should output 2 buttons with icon and one button should have active element.
For some reason I am not able to see anything. It works without problem when I use same code in Main.xaml/Main.xaml.cs. Maybe there is limitation on Application class that prevents databinding?
App.Xaml
<!--test-->
<ListView ItemsSource="{Binding NavigationItemss}">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout>
<Label Text="{Binding Icon}"></Label>
<Label Text="Testing"></Label>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<!--test-->
App.xaml.cs
public partial class App : Application
{
//TODO: Replace with *.azurewebsites.net url after deploying backend to Azure
public static string AzureBackendUrl = "http://localhost:5000";
public static bool UseMockDataStore = true;
Navigation AppNavigation = new Navigation();
public App()
{
InitializeComponent();
if (UseMockDataStore)
DependencyService.Register<MockDataStore>();
else
DependencyService.Register<AzureDataStore>();
this.BindingContext = AppNavigation;
MainPage = new NavigationPage(new Main());
}
Navigation.cs
using HOT_App.Views;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.ComponentModel;
using System.Text;
using Xamarin.Forms;
namespace HOT_App.ViewModels
{
class Navigation
{
//public List<NavigationItem> NavigationItems;
public ObservableCollection<NavigationItem> NavigationItemss { get; set; }
public Navigation()
{
NavigationItemss = new ObservableCollection<NavigationItem>();
//NavigationItems = new List<NavigationItem>();
NavigationItem Home = new NavigationItem("Home","NavigationHome.png",true);
NavigationItem Trends = new NavigationItem("Trends","NavigationTrend.png",false);
NavigationItemss.Add(Home);
NavigationItemss.Add(Trends);
//NavigationItems.Add(Home);
//NavigationItems.Add(Trends);
}
public void ShowActiveNavigation()
{
System.Diagnostics.Debug.WriteLine(string.Join<NavigationItem>("\n", NavigationItemss));
}
public void SetActiveNavigation(string activeNavigationName)
{
ChangeActiveValue(activeNavigationName);
switch (activeNavigationName)
{
case "Home":
//activeNavigation = new NavigationItem("Home");
Application.Current.MainPage.Navigation.PushAsync(new Main(), false);
System.Diagnostics.Debug.WriteLine("Home");
break;
case "Trends":
//activeNavigation = new NavigationItem("Trends");
Application.Current.MainPage.Navigation.PushAsync(new Trends(), false);
System.Diagnostics.Debug.WriteLine("Trends");
break;
default:
//activeNavigation = new NavigationItem("Home");
Application.Current.MainPage.Navigation.PushAsync(new Main(), false);
System.Diagnostics.Debug.WriteLine("Home");
break;
}
}
public void ChangeActiveValue(string activeNavigationName)
{
foreach(NavigationItem navigationItem in NavigationItemss)
{
if (navigationItem.NavigationItemName == activeNavigationName)
{
navigationItem.Active = true;
}
else { navigationItem.Active = false; }
}
}
}
}

Answer 1

Normally we don't create pages in App.xaml
i think MasterDetailPage is the the fastest way to solve your problem, you just need to configure Master and Detail page,Master page here is your navigation page which you use ListView,and the detail page is your Main and Home pages.
you could refer to the MasterDetails Page
ps: you could also use Shell if your Xamarin.Forms is 4.0 and above

Answer 2

DataBinding works inside the controlTemplate as well. You can find more info about it here.
https://learn.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/templates/control-templates/template-binding