Login.xaml.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using UEngage.Models;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;

namespace UEngage
{
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class Login : ContentPage
    {
        public Login()
        {
            InitializeComponent();

        }

        private void btnsignup_Clicked(object sender, EventArgs e)
        {
            Navigation.PushModalAsync(new Signup());
        }

        private async void btnlogin_Clicked(object sender, EventArgs e)
        {

            try
            {
                if (!string.IsNullOrEmpty(txtusername.Text) || !string.IsNullOrEmpty(txtpassword.Text))
                {

                    User_ user = App.Database.GetUserAsync(txtusername.Text).Result;
                    if (user.Password == txtpassword.Text)
                    {

                        busyIndi.IsVisible = true;
                        await Task.Delay(1000);
                        Constant.loggedUser = user;
                        Application.Current.MainPage = new Tabbed();
                        busyIndi.IsVisible = false; ;
                    }
                    else
                    {
                        DisplayAlert("", "invalid username or password", "Ok");
                    }

                }
                else
                {
                    DisplayAlert("", "invalid username or password", "Ok");
                }
            }
            catch (Exception)
            {
                DisplayAlert("", "You dont have an account. Please signup", "Ok");
                return;
            }


           
        }


        /*async void OnSignUpClicked(object sender, EventArgs e)
        {
        }*/
    }
}