RGBController/RGBController2/ViewModels/MainViewModel.cs

using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Collections.Specialized;
using System.Text;
using System.Windows.Input;
using RGBController2.Commands;
using RGBController2.ViewModels.Tabs;

namespace RGBController2.ViewModels
{
    class MainViewModel
    {
        private readonly ObservableCollection<ITab> _tabs;
        public ICommand NewTabCommand { get; }
        public static ICollection<ITab> Tabs { get; set; }

        public MainViewModel()
        {
            NewTabCommand = new ActionCommand(p => NewTab());

            _tabs = new ObservableCollection<ITab>();
            _tabs.CollectionChanged += Tabs_CollectionChanged;

            Tabs = _tabs;
        }

        private void Tabs_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)
        {
            ITab tab;

            switch (e.Action)
            {
                case NotifyCollectionChangedAction.Add:
                    tab = (ITab) e.NewItems[0];
                    tab.CloseRequested += OnTabCloseRequested;
                    break;
                case NotifyCollectionChangedAction.Remove:
                    tab = (ITab) e.OldItems[0];
                    tab.CloseRequested -= OnTabCloseRequested;
                    break;
            }
          
        }

        private void OnTabCloseRequested(object sender, EventArgs e)
        {
            Tabs.Remove((ITab) sender);
        }

        private void NewTab()
        {
            Tabs.Add(new ArduinoTab(DateTime.UtcNow.ToString()));
        }
    }
}