AddingDeletingEditingData/DatabaseMVVMApp/ViewModels/AllTeachersViewModel.cs

using System;
using Avalonia.Controls;
using System.Collections.Generic;
using ReactiveUI;
using DatabaseMVVMApp.Models;
using System.Linq;
using Microsoft.EntityFrameworkCore;
using System.Threading;
using MsBox.Avalonia;
using MsBox.Avalonia.Models;
using Avalonia.Notification;

namespace DatabaseMVVMApp.ViewModels
{
	public class AllTeachersViewModel : ReactiveObject
	{
        public List<Teacher> Teachers => MainWindowViewModel.connection.Teachers.Include(x => x.Gender).Include(x => x.TeachersCourses).ThenInclude(x => x.Course).Include(x => x.TeachersSubjects).ThenInclude(x => x.Subject).ToList();
        public string Count => Teachers.Count().ToString();

        public INotificationMessageManager Manager { get; } = new NotificationMessageManager();

        public void ToAddPage()
        {
            MainWindowViewModel.Instance.Control = new AddTeacher();
        }
        
        public async void DeleteTeacher(int id)
        {
            var box = MessageBoxManager.GetMessageBoxCustom(
                new MsBox.Avalonia.Dto.MessageBoxCustomParams {
                    ButtonDefinitions = new List<ButtonDefinition> {
                        new ButtonDefinition { Name = "Äà",},
                        new ButtonDefinition { Name = "Îòìåíà",},
                    },
                    ContentTitle = "Ïðåäóïðåæäåíèå",
                    ContentMessage = "Âû óâåðåííû ÷òî õîòèòå óäàëèòü äàííûå ó÷èòåëÿ?",
                    Icon = MsBox.Avalonia.Enums.Icon.Warning,
                    WindowStartupLocation = WindowStartupLocation.CenterOwner,
                    CanResize = false,
                    MaxWidth = 500,
                    MaxHeight = 800,
                    SizeToContent = SizeToContent.WidthAndHeight,
                    ShowInCenter = true,
                    Topmost = false
                });

            var result = await box.ShowAsync();
            if (result == "Äà") 
            {
                Teacher deleteTeacher = MainWindowViewModel.connection.Teachers.First(x => x.Id == id);
                MainWindowViewModel.connection.Teachers.Remove(deleteTeacher);
                MainWindowViewModel.connection.SaveChanges();
                MainWindowViewModel.Instance.Control = new AllTeachers();
                var box1 = MessageBoxManager.GetMessageBoxCustom(
                new MsBox.Avalonia.Dto.MessageBoxCustomParams
                {
                    ButtonDefinitions = new List<ButtonDefinition> {
                        new ButtonDefinition { Name = "Îê",},
                    },
                    ContentTitle = "Óâåäîìëåíèå",
                    ContentMessage = "Ó÷èòåëü áûë óñïåøíî óäàëåí",
                    Icon = MsBox.Avalonia.Enums.Icon.Success,
                    WindowStartupLocation = WindowStartupLocation.CenterOwner,
                    CanResize = false,
                    MaxWidth = 500,
                    MaxHeight = 800,
                    SizeToContent = SizeToContent.WidthAndHeight,
                    ShowInCenter = true,
                    Topmost = false
                });

                await box1.ShowAsync();

            }
        }



        public void UpdateTeacher(int id) 
        {
            MainWindowViewModel.Instance.Control = new AddTeacher(id);
        }

    }

    
}