App.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Prism.Unity;
using Xamarin.Forms;
using Prism.Ioc;
using Prism;
using XamarinFormPrism.Views;

namespace XamarinFormPrism
{
    public partial class App : Prism.Unity.PrismApplication
    {
        public App(IPlatformInitializer platformInitiliser = null) : base(platformInitiliser)
        {
        }

        protected override void OnInitialized()
        {
            InitializeComponent();
            NavigationService.NavigateAsync("NavigationPage/HomePage");
        }

        protected override void RegisterTypes(IContainerRegistry containerRegistry)
        {
            containerRegistry.RegisterForNavigation<NavigationPage>();
            containerRegistry.RegisterForNavigation<HomePage>();
        }

        protected override void OnStart()
        {
            // Handle when your app starts
        }

        protected override void OnSleep()
        {
            // Handle when your app sleeps
        }

        protected override void OnResume()
        {
            // Handle when your app resumes
        }
    }
}